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					                                                 TUESDAY, 22 SEPTEMBER

               Keynote Address
               Research in barnacles: Working in Darwin’s footsteps
                       Jens Høeg
                          Comparative Zoology, Department of Biology, University of Copenhagen, Denmark

               Unravelling the evolution of complex biological systems, such as reproductive strategies and
               complicated metamorphoses between larvae and adults, requires both detailed comparative studies
               and a robust phylogeny on which to interpret the observations. Darwin wrote to Hooker: “I have
               been getting on well with my beloved Cirripedia”, and since his pioneering efforts, barnacles have
               offered excellent models in evolutionary research. Indeed, prior to publishing the “Origin of Species”
               he dedicated almost 10 years to the study of these animals, which can perhaps be called the first
               “model organisms”. This lecture will explain the specializations found in barnacles with focus on
               their reproductive systems and how basically similar larvae result in morphologically and biologically
               diverse life styles at the adult stage. Cirripede life styles vary from thoracopodal filtrators to some of
               the most intriguing parasites known in all Metazoa. Furthermore, barnacles have evolved a spectrum
               of reproductive systems, ranging from pure hermaphroditism to a variety of schemes, where large
               females or hermaphrodites are associated with one or several highly specialized dwarf males. As
               already understood by Darwin, this offers an exciting testing ground for models on the evolution of
               reproductive systems. Settlement of the cypris larva is closely linked to the mode of reproduction
               and proceeds very differently in pure hermaphrodites and species with a free male sex. The cyprid
               morphology sports many features that enable it to locate and attach to a suitable settlement site.
               Phylogenetically these cyprid traits become autapomorphies for the Cirripedia. But while cirripede
               cyprids are overall surprisingly similar, significant differences between the taxa only comes to light at
               the onset of metamorphosis. Here I will illustrate a remarkable case of convergence that has recently
               come to light between the rhizocephalan barnacles and the facetotectan y-larvae. The lecture will
               be rich in videos, documenting larval settlement, metamorphosis and events in reproduction “but
               [paraphrasing Darwin] I can hardly explain what I mean, & you will perhaps wish my Barnacles and
               their cyprids al Diabolo together.”




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oral.indd 28                                                                                                               09.8.13 9:53:00 AM
               Symposium S11: The New Perspective on Barnacle Research

               [S11-1] Male settlement and receptacle structures in acrothoracican, rhizocephalan and
                      scalpellid thoracican cirripedes
                       Jens T. Høeg1), Uwe Spremberg1), Yoichi Yusa2), Benny K.K. Chan3), Lene Buhl-Mortensen4)
                          1)
                           Department of Biology, University of Copenhagen, Denmark; 2) Nara Women’s University, Japan; 3) Research
                          Centre for Biodiversity, Academia Sinica, Taiwan; 4) Institute of Marine Research, Bergen, Norway

               Dwarf males are found in many cirripedes and can be associated with either females or hermaphrodites.
               Their number and the degree of specialization of the site where they attach varies extensively, but has
               been little studied both morphologically and in an evolutionary context. In the Acrothoracica, males
               are simply fixed on the external surface of the female, often in great numbers. In rhizocephalans, the
               female parasite has a pair of highly specialized receptacles located in the mantle cavity, where the two
               implanted males are kept and nourished. These males can only be acquired by juvenile parasites, but
               remain with them for life. In the Thoracica Scalpellidae, males are generally non-feeding, but they can
               be repeatedly replaced by settlement of new cyprids on the female or hermaphrodite. Ornatoscalpellum
               stroemii females carry two males, housed in a pair of narrow and deep receptacle pockets, situated on
               either side of the mantle aperture close to the adductor muscle. Scalpellum scalpellum has two more
               spacious receptacles in the same position, each of which houses up to five males. In Arcoscalpellum
               alcockianum the two receptacles are even larger, consisting of a system of crevices in the mantle wall
               that can accommodate more than 20 males. Finally, in Scalpellum stearnsii, the males are not sited in
               a pair of receptacles, but sit scattered, often in large numbers, individually or in small groups along
               the lower margin of the mantle aperture. We use videos to document the settlement of male cyprids
               and the structure of the receptacles in light and scanning electron microscopy. We furthermore discuss
               the possible homology and evolution of the receptacle structures and other features of the cirripede
               reproductive systems.




               [S11-2] Barnacle phylogenetics: last insights on the evolution on the first model
                       organism
                       Marcos Pérez-Losada1), Jens Høeg2), Keith Crandall3)
                          1)
                               CIBIO, Portugal; 2) Department of Biology, University of Copenhagen, Denmark; 3) Brigham Young University

               The Thecostraca (Facetotecta, Ascothoracida and Cirripedia) are arguably the most morphologically
               and biologically variable group within the Crustacea. In fact, their specializations in adult morphology,
               growth, feeding biology and sexual systems prompted Darwin to study cirripedes as first “model
               organisms” of evolutionary adaptation. However, for a group that has been the focus of intense study
               for almost two centuries, only relatively recently are their phylogenetic relationships being unraveled.
               The combination of molecular and morphological evidence into new maximum likelihood and
               Bayesian analytical frameworks is now allowing researchers to explore not only barnacle evolutionary
               relationships but also time their radiation. Here we review some of these analytical tools and present
               our latest results on Thecostraca evolution. Using these approaches thecostracan main relationships
               have been depicted as (Facetotecta, (Ascothoracida, (Acrothoracica, (Rhizocephala, Thoracica)))).
               This indicates that the very similar ypsigon and vermigon larval stages arose independently in the
               Facetotecta and the Rhizocephala and provides a remarkable case of convergent evolution. Within the
               Thoracica, our analyses have showed that: 1) shell plates were present in the last common ancestor
               to all extant Thoracica but were later lost at least twice in their evolution; 2) the ontogenetic pattern
               with 5 → 6 → 8 → 12+ plates does not reflect shell evolution; 3) asymmetry and loss of a peduncle
               have evolved twice, resulting in neither the Verrucomorpha nor the Sessilia being monophyletic in
               their present definitions; 4) the Thoracica suborders evolved since the Early Carboniferous (340 mya)
               with the final radiation of the Sessilia in the Upper Jurassic (147 mya). These results, therefore, reject
               many of the underlying hypotheses about character evolution in the group, stimulate a variety of
               new thoughts on thoracican radiation, and suggest the need for a major rearrangement in thoracican
               classification based on estimated phylogenetic relationships.




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oral.indd 29                                                                                                                               09.8.11 9:06:39 AM
               Symposium S11: The New Perspective on Barnacle Research

               [S11-3] Diversity and speciation of the coral-dwelling barnacles (Balanomorpha:
                      Pyrgomatidae)
                       Maria Celia (Machel) Malay
                          Florida Museum of Natural History, University of Florida, USA


               The pyrgomatids are a group of balanomorph barnacles that obligately dwell on the surface of living
               scleractinian corals (a few species also inhabit hydrocorals and sponges). Despite their relative
               obscurity, the evolutionary success of these coral-dwelling barnacles is clear: from their origins in the
               late Oligocene, pyrgomatids have collectively colonized over 200 different host species, and are very
               common (although commonly overlooked) on coral reefs. Pyrgomatids are among the few organisms
               that are capable of inhabiting living coral tissue, and they have evolved unique adaptations that allow
               them to successfully exploit this niche, including highly derived and reduced skeletal elements and
               host parasitism in one lineage. I am interested in elucidating the systematics, evolution, and diversity
               patterns of pyrgomatid barnacles using a combination of molecular and morphological techniques.
               My work shows higher species-level diversity and greater host-specificity than had been previously
               reported. Opercular plate fusion clearly evolved multiple times and is not an adequate basis for
               delineating genera. I will also discuss patterns of pyrgomatid speciation in the Indo-West Pacific and
               how speciation is influenced by geography and host specificity.




               [S11-4] An integrated approach to the study of Cirripedia symbioses: DNA, morphol-
                      ogy and host specificity
                       Robert J. Van Syoc
                          Invertebrate Zoology and Geology, California Academy of Sciences, USA

               Sponge-inhabiting Cirripedia in the subfamilies Acastinae and Bryozobiinae, and the archaeobalanid
               genus Membranobalanus, are compared morphologically, at the molecular-level with DNA sequences
               and host specificity. Bryozobiines are known only from bio-eroding sponges on calcareous substrata.
               They have evolved perhaps the most intricate adaptations to life with sponges, a system of radial atria
               and wall portals into which their host grows and expands. However, they remain (tenuously in many
               cases) attached to the hard substratum inhabited by the sponge. Acastines and Membranobalanus,
               on the other hand, have relatively simple morphological adaptations to life in sponges. Species in
               these groups are not attached to hard substrata beneath their host sponge, rather they are completely
               encased by sponge tissue except at the opercular orifice. They have evolved a vertical growth pattern
               to keep up with the surface growth of sponge. Acastines commonly have elongated, cup-shaped or
               columnar bases and long wall plates, species of Membranobalanus usually have an elongated rostrum,
               or other wall plates. DNA sequence analysis provides a molecular-level view of relationships that
               is currently limited by access to appropriate material from some taxa. All three groups of sponge-
               inhabiting barnacles have at least some (or all) members living with clionid sponges. This is probably
               the ancestral condition, with recently evolved relationships with non-clionid sponge taxa, primarily in
               the Acastinae.




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oral.indd 30                                                                                                               09.8.11 9:06:39 AM
               Symposium S11: The New Perspective on Barnacle Research

               [S11-5]     Revision of Amphibalaninae from morphological evaluation and evolutionary
                         trends of the subfamily
                       Fabio B. Pitombo
                          Departamento de Biologia Marinha, Universidade Federal Fluminense, Brazil

               The recently proposed Amphibalaninae, reflects early attempts on furnishing an evolutionary
               framework for the Balanidae. Previous authors already grouped amphibalanines under informal
               names reflecting their suspicion of a monophyletic group. Although recognized as monophyletic
               Amphibalaninae do not present relationship proposal among and within its three genera: Amphibalanus,
               Fistulobalanus and Tetrabalanus. Most of its 25 extant species are usually found on sheltered and
               estuarine habitats being common as a fouling component and consequently turning into an invasive
               species in many regions of the world. This lead to the fact that many species of Amphibalaninae had its
               origin unknown, cryptogenic, due to their early man made dispersal. This contribution aims to evaluate
               some already used morphological features and discuss some usages on the systematic of the subfamily.
               Characters are examined and new interpretations are proposed especially for those that are of common
               use on Amphibalaninae taxonomy such as spur shape, number of teeth on labrum, types of setae, wall
               structure among others. New interpretations of character evolution are furnished in order to better
               access the relationships within the subfamily. The synapomorphies of Amphibalaninae [articular ridge
               of the scutum with a long basal projection; depressor muscle crests projecting beyond the basal margin
               of the tergum; tergal spur and furrow margins coincident and smooth setae on the distal lobe of the
               second maxilla having enlarged modified tips] are evaluated in a comparative framework, and further
               interpretations of its evolution are also furnished.




               [S11-6]     Indo-West Pacific biogeographic research and speciation among
                         Amphibalaninae
                       Romanus E. Prabowo1), Toshiyuki Yamaguchi2
                          1)                                                                  2)
                           Faculty of Biology, University of Jenderal Soedirman, Indonesia;        Department of Earth Sciences, Graduate
                          School of Science, Chiba University, Japan

               Four barnacle regions were recognized in Indo-West Pacific i.e.; Indo-Malayan, Eastern Indonesian
               (including Okinawa), Southern and Eastern Australian and New Zealand. Species contribution
               values suggest that all regions dominated by Amphibalaninae especially Indo-Malayan and Eastern
               Indonesian. The origin of those two barnacle regions relates closely to the paleo-coastlines before Plio-
               Pleistocene sea level changes. Some new morpho-species revealed in this study, i.e.: F. sumbawaensis,
               a new species from Indo-Malayan region and two new species from Eastern Indonesian region.
               The taxonomic position of two distinct populations of the Amphibalanus variegatus from Asia
               and Australia has also been corrected, and elevated Asian population as a new species. The works
               of Harding (1962) and Henry & McLaughlin (1975) on A. variegatus showed a slightly different
               morphological description, since each of them referred to two different populations mentioned above.
               Fistulobalanus kondakovi has also been reported to occur in Australia apart from its typical population
               in Japan due to some morphological similarity to Australian A. variegatus. A work on these two species
               including 8 other amphibalanids on historical taxonomy, morphology, biogeography, and phylogeny,
               was performed to solve their correct species assignment. This research compared 14 populations;
               of which 5 represent Asian A. variegatus, 5 Australian A. variegatus, and 5 Asian F. kondakovi. The
               molecular evidence based on COI gene sequences showed there are five lineages of this two species.
               The phylogram shows deep split branching of those 5 lineages. Pairwise genetic distances and genetic
               differences values suggest those 5 lineages are significantly distinct species. Australian populations of A.
               variegatus differ to their Asian sister and assigned as true A. variegatus. Asian populations previously
               known as A. variegatus elevated as new species, of which 1 population from Indonesia is a cryptic
               species.



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oral.indd 31                                                                                                                                09.8.11 9:06:39 AM
               Symposium S10: Reproductive Behavior of Decapod Crustaceans

               [S10-1] Sexual selection and the behavioral ecology of fiddler crab reproduction
                       John H. Christy
                          Smithsonian Tropical Research Institute, USA

               Studies of fiddler crab (genus Uca) reproductive ecology suggest that natural selection on females
               and larvae establish female preferences which in turn largely determine for what and how males
               compete for mates. I will review three examples of fiddler crab reproductive behavior that illustrate
               these connections. On sand beaches on the west coast of Florida the locations of the burrows of male
               Uca pugilator that are suitable for breeding vary with the biweekly tidal amplitude cycle because
               these burrows collapse when they are flooded by ground water. Females prefer to mate with males
               who defend high, relatively deep and stable burrows, males compete for these burrows and male
               reproductive success is strongly correlated with the amount of time they are able to defend them.
               Comparative studies corroborate female choice based on burrow quality in other species. Studies
               of reproductive timing by fiddler and other intertidal crabs indicate that predation on newly hatched
               larvae selects for larval release on large amplitude nocturnal tides. In Uca terpsichores precise timing
               of larval release is anticipated by precise timing of female mate choice which in turn determines when
               it is most profitable for males to court females. This results in a remarkably precise match between
               temporal variation in male investment in courtship signaling and female variation in sexual receptivity.
               Finally, to choose a mate, females often must leave their burrows and be exposed to elevated predation
               risk. Studies of sexual signaling in U. terpsichores, U. beebei and U. puglilator show how male signals
               have been shaped by features of female sensory systems that are used to detect and escape from
               predators. Thus, both spatial and temporal features of the ecology of mate choice and reproduction
               shape female preferences which in turn strongly affect how males compete for mates both directly and
               through courtship signaling.



               [S10-2] Sexual selection and extended parental care in crayfish
                       Francesca Gherardi, Laura Aquiloni
                          Department of Evolutionary Biology, University of Florence, Italy

               We will discuss some traditional concepts of the sexual selection theory using crayfish as model
               organisms. As expected, female crayfish are highly choosy and invest more time and energy than the
               other sex in parental care, whereas male crayfish are typically ‘ardent’ and exhibit some morphological
               traits that attract the females. But males are also subject to physiological, behavioral and ecological
               constraints that make them selective versus their potential mates. Crayfish females prefer mates with
               large body size, being even able to reduce their reproductive investment when forced to copulate
               with small males. Large and/or symmetric chelae seem not to be attractive, whereas male ornaments
               may also serve as choice criteria. Finally, dominant individuals, at least in P. clarkii, are preferred
               over subordinates only when the choosing female eavesdrops on the two males fighting. Because
               of the large number of cheap sperm they produce, males are usually thought to be limited in their
               reproductive success only by the frequency of the fertilizations achieved. On the contrary, sperm
               supply may be short in some crayfish species: sperm limitation, combined with long copulation times,
               large investment in sperm production and restricted mating periods, has induced the evolution of a
               form of mate selection in crayfish males. They have also evolved means to reduce the risk of sperm
               competition by feeding on the already deposited spermatophores in Astacidae or by adjusting the
               length of copulation with the female mating status, depositing a plug in the opening of the female
               seminal receptacle, removing the plug of a previous male, or selecting virgin females in Cambaridae.
               Overall the case studies we will discuss show that several aspects of the crayfish reproductive behavior
               might clarify some debated issues of sexual selection; future research in this taxon is thus expected to
               deserve many surprises.




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oral.indd 32                                                                                                              09.8.11 9:06:40 AM
               Symposium S10: Reproductive Behavior of Decapod Crustaceans

               [S10-3] Perceived predation risk and acquisition of a mate jointly alter the outcome of
                      territorial fights
                       Tsunenori Koga
                          Faculty of Education, Wakayama University, Japan

               Virtually all animal conflicts occur over access to mates or resources that affect survival, the two
               key components of fitness. Here we show how predation risk and mate availability jointly affect
               the outcomes of contests between male sand crabs Scopimera globosa for burrows in which crabs
               mate and take shelter from predators. Under natural conditions of low predation risk and without
               the presence of a female the larger crab usually won, whether he was the resident or the intruder. We
               imposed perceived risk to intruders by capturing males and placing them in the opening of other males’
               burrows. Accounting for size differences between residents and forced intruders, intruders fought
               harder and won more fights. We repeated this manipulation but increased the value of the burrow
               to the resident by giving him a female or allowing him to take one into his burrow. Then, the fights
               escalated significantly and, correcting for male size differences, residents tended to win. Thus residents
               fought harder to maintain access to potential mates than did intruders to gain access to shelter. This is
               the first report of two external factors simultaneously raising resource value, affecting motivation of
               contestants and altering the outcome of fights.




               [S10-4] Male mate choice of Pagurus hermit crabs
                       Satoshi Wada
                          Graduate School of Fisheries Sciences, Hokkaido University, Japan

               Many behavioral studies in crustaceans have focused on male-male competition and female mate
               choice. Male mate choice has been paid less attention especially in species with male biased
               operational sex ratio. Male mate choice can be expected in species where female quality is variable,
               male mating investment is high and encounter rate with mature females is also high. We examined male
               mate choice in Pagurus hermit crabs where these conditions are met. In P. filholi, P. middendorffii, P.
               nigrivittatus, P. nigrofascia and P. proximus, males guard receptive females by grasping the rim of the
               female’s shell with his minor cheliped for a few days. Female fecundity (i.e., clutch size) was highly
               variable and correlated with female body size in all of these species. Feeding activities of both sexes
               were limited during guarding. Females did not seem to actively resist males that attempt guarding.
               Although their operational sex ratio is male biased, encountering mature females might not always
               be rare because their density is high in the study sites. Males of P. middendorffii chose larger females
               in our experiments. Interestingly, some males replaced their mates during guarding. This suggests
               that a male hermit crab could assess another female while guarding because their major cheliped and
               legs are not used for guarding, and thus the mechanical characteristics of guarding in Pagurus hermit
               crabs might be important for the possibility of male mate choice and mate replacement. Interspecific
               variation in male mate choice with regards to life history traits is discussed.




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oral.indd 33                                                                                                               09.8.13 8:50:10 AM
               Symposium S10: Reproductive Behavior of Decapod Crustaceans

               [S10-5] Mating behavior and the control of mating in the blue crab, Callinectes sapidus
                       Paul Jivoff
                         Rider University, Department of Biology, USA

                    In the past decade, we have increased our understanding of the blue crab mating system and the
               factors that influence individual mating success. Blue crabs engage in both pre- and post-copulatory
               mate guarding. Males compete for access to females and their unfertilized eggs, and may invest
               considerable time and energy in mating. Individual male characteristics, such as male size, molt stage,
               and limb loss influence a male's ability to compete and invest in mating. Mating system theory predicts
               that males will exert more control over mating than females, yet it is clear that the behavior of female
               blue crabs towards males influences courtship and pre-copulatory mate guarding. It is less clear as
               to the role of each sex in how post-copulatory mate guarding, and thus sperm competition, occurs in
               blue crabs. Pheromones are known to influence courtship in blue crabs and recent preliminary work
               suggests how these pheromones may influence the post-copulatory phase of mating in blue crabs. The
               control of the post-copulatory mate guarding phase of mating will be placed in the context of other
               factors that influence individual mating success.




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oral.indd 34                                                                                                              09.8.13 8:50:10 AM
               Symposium S9: Symbiosis in Crustaceans: Diversity and Evolutionary Trends


               [S9-1] The evolution of parasitism in the Copepoda – new insights from 18S rDNA data
                        Rony Huys, Julia Llewellyn-Hughes
                          Department of Zoology, Natural History Museum, London, UK

               No group of plants or animals on Earth exhibits the range of morphological diversity as seen among
               the extant Crustacea. This structural disparity is best demonstrated by the Copepoda, which by virtue
               of their immense vertical distribution are also arguably the most abundant metazoans. Their current
               position of world predominance can be attributed to two principal, recurrent, radiation events, i.e. their
               major habitat shift into the marine plankton, and the evolution of parasitism. Given their moderately
               high host specificity in conjunction with the incredible spectrum of potential marine hosts, it is highly
               conceivable that parasitic copepods significantly outnumber their free-living counterparts in species
               diversity. Their successful colonization or utilization of virtually every metazoan phylum has generated
               a great diversity in copepod body morphology, which is arguably unparalleled among the Crustacea.
               For example, some highly modified copepods such as the polychaete-associated Herpyllobiidae and
               Melinnacheridae lack any external trace that could positively identify their crustacean affinity and their
               divergent body plans defy any attempts to place them in a higher level classification on morphological
               grounds alone. Other families such as the Monstrillidae and Thaumatopsyllidae demonstrate how
               extremely powerful natural selection can be in shaping morphology to meet functional needs so that
               distantly related taxa may appear uncannily similar. Here I will show how small subunit ribosomal
               sequence data (18S rDNA) can help resolving controversial issues that had reached a temporary
               impasse in the phylogeny and classification of the symbiotic copepods, such as the placement of
               the Thaumatopsyllidae, the paraphyly of the Cyclopoida and the origin of parasitism in freshwater.
               I will demonstrate how the use of such data can lead to the discovery of previously overlooked
               morphological characters and how they impact on the ordinal level classification of the Copepoda.




               [S9-2]     The significance of the stylet in the evolution of the parasitic barnacles
                         (Rhizocephala)
                        Henrik Glenner1), Martin Hebsgaard2), Jesper Stenderup3), Jens Høeg3)
                          1)
                               University of Bergen, Norway; 2) University of Edinburgh, Scotland; 3) University of Copenhagen, Denmark

               Effective parasite-to-host transmission is vital to the evolutionary success of parasites. In parasitic
               barnacles transmission has been accomplished by the development of a unique device, the stylet, which
               in one smooth, continuous movement penetrates the integument of the host and injects the parasitic
               material into its hemolymph. Inside the host the juvenile parasite, the vermigon, migrates through the
               hemolymph to a target organ where it initiates an internal growth phase. Close examination of the
               stylet formation and penetration process has revealed new, surprising morphological information that
               significantly corroborate the understanding of the enigmatic, evolutionary process that transformed a
               filterfeeding epibiontic ancestor to an endo-parasitic rhizocephalan.




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oral.indd 35                                                                                                                              09.8.11 9:06:40 AM
               Symposium S9: Symbiosis in Crustaceans: Diversity and Evolutionary Trends

               [S9-3] Symbiosis in planktonic crustaceans: diversity and interaction
                       Susumu Ohtsuka1), Yukio Hanamura2), Takeo Horiguchi3), Atsushi Yamaguchi4), Michitaka
                       Shimomura5), Toshinobu Suzaki6)
                          1)
                            Takehara Marine Science Station, Hiroshima University, Japan; 2)Japan International Research Center for
                          Agricultural Sciences, Tsukuba, Japan; 3) Graduate School of Science, Hokkaido University, Japan; 4) Graduate
                          School of Fisheries Sciences, Hokkaido University, Japan; 5) Kitakyushu Museum of Natural History and Human
                          History, Japan; 6) Faculty of Science, Kobe University, Japan

               Planktonic crustaceans such as copepods and mysids are composed of the most important components
               in the marine zooplankton community, and they also harbor a variety of symbionts. However, mutual
               interactions between the hosts and symbionts are poorly understood to date. We therefore have been
               intensively investigating symbiotic diversity and impact on these hosts. These interactions range from
               phoresy through parasitism to parasitoidism. The present study briefly reviews symbionts on copepods
               and mysids based on our researches. The apostome ciliate Vampyrophrya pelagica on copepods are
               suggested to exhibit negative impacts on copepod individuals and further on populations due to high
               prevalence and worldwide distributions, and consequently, it influences the population dynamics of
               higher trophic levels such as chaetognaths and medusae. In contrast symbiosis between copepods
               and epibionts such as diatoms and suctorian ciliates can be regarded as typical commensalism. Some
               suctorains and diatoms tend to prefer carnivores as their host rather than particle-feeders. Endoparasitic
               alveolates such as Syndinium are truly parasitoids. A dajid isopod and a nicothoid copepod compete
               for the space and possibly, food within the marsupium of the same host mysid Siriella okadai.
               The parasitic isopods and copepod clearly showed an alternative seasonal occurrence, supposing
               antagonism between them. The egg production of the host seems to be remarkably suppressed by
               these parasites. Since the adults of the parasites appeared within the host marsupium in line with the
               maturity of the host, peculiar prepositioning behaviors of immature parasites were observed within the
               body tissue for the nicothoid and in a space between the carapace and tergites for the dajid. Epibiont
               peritrich ciliates on the body of gastrosaccini mysids which is referred as to commensalism, showed
               a high host-specificity and a distinct geographic cline. This phenomenon might be explained by the
               behaviors and distributions of the host.


               [S9-4] Adaptation in Stenopodidean Shrimps
                       Tomomi Saito
                          Port of Nagoya Public Aquarium, Japan

               The morphology, taxonomy and ecology of the stenopodidean shrimp families, Stenopodidae,
               Spongicolidae and Macromaxillocarididae are overviewed. Their habitats can be divided into three
               groups: littoral/sublittoral forms, which usually utilize rocky bottoms or coral reefs; deep-water
               forms on muddy substrates or mostly as commensals in hexactinellid sponges; and stygobitic in
               marine caves. Their typical adaptations to the habitats are introduced. Spongicolidae accommodate
               34 described species of 6 genera: Globospongicola, Microprosthema, Paraspongicola, Spongicola,
               Spongicoloides and Spongiocaris. Only Microprosthema comprises free living species in shallow
               rocky reefs, however, shrimps of the other genera are primarily obligate symbionts of deep-water
               hexactinellid sponges, living in the atrium of hosts. The loss of gills, exopods on the second and third
               maxillipeds, and spiniation on carapace, pereopods and abdomen in the shrimps of the Spongicolidae
               (except for Microprosthema) are considered as secondarily-derived characteristics in relation to their
               sponge-associated habitat. Macromaxillocarididae evolved as a monotypical cave shrimp, which has
               unique features such as reduced eyes, massive third maxillipeds, and elongated slender appendages.
               Stenopodidae contain 28 described species of 4 genera: Engystenopus, Odontozona, Richardina and
               Stenopus. The family distributes widely from shallow, warm waters to deep-sea. The morphology
               of the stenopodids is compared with that of the other two symbiotic and stygobitic families. Larval
               development and geographic and bathymetric distributions of the stenopodidean shrimps are discussed.




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oral.indd 36                                                                                                                              09.8.11 9:06:41 AM
               Symposium S9: Symbiosis in Crustaceans: Diversity and Evolutionary Trends

               [S9-5] Symbiotic relationships in the burrows of upogebiid shrimps in Japan
                       Gyo Itani
                          Faculty of Education, Kochi University, Japan

               Animal burrows are ubiquitous in marine sediments. They provide safe habitats for the owners (hosts)
               and guests (symbiotic animals). Symbiotic relationships in the burrows of the echiuran worm Urechis
               caupo in California estuary are well documented in MacGinitie (1935) and MacGinitie and MacGinitie
               (1949), and are referred to frequently in textbooks of Marine Biology. However such symbiosis was
               not closely investigated in the Western Pacific until recently. Upogebiid mud shrimps are common
               burrowers in tidal flats worldwide. I have collected symbiotic animals from the shrimp burrows in tidal
               flats in western Japan. Upogebiid burrows were utilized by the scale worm Hesperonoe hwanghaiensis,
               the myid bivalve Cryptomya truncata, the alpheid shrimps Stenalpheops anacanthus and Athanas
               sp., and the pinnotherid crab Pseudopinnixa carinata and the varunid crabs Sestrostoma toriumii (=
               Acmaeopleura toriumii) and S. depressum (= A. depressa). Some gobiid fishes (e.g. Eutaeniichthys
               gilli) were facultative symbionts that used shrimp burrows as tentative shelter. Exoskelton of
               mud shrimps was attachment substrate for obligate symbionts, such as the galeommatid bivalves
               Peregrinamor ohshimai and P. gastrochaenans, and the varunid undescribed crab. The bopyrid isopod
               phyllodurus sp. was found attached to the pleopod of the shrimp, though the most bopyrids were
               in the branchial chamber. Behaviour of the ectosymbionts through host ecdyses were observed and
               described. The diversity of symbiotic animals associated with upogebiid shrimps is higher than that
               associated with Urechis, probably because upogebiids create habitat for both burrow associateds and
               ectosymbionts.




               [S9-6] Symbiotic crustaceans as model systems in behavioral ecology
                       J. Antonio Baeza
                          Smithsonian Marine Station at Fort Pierce, USA

               One outstanding topic in behavioral ecology is explaining the diversity of behavioral traits, including
               mating systems and complex social interactions, of marine and terrestrial organisms. Crustaceans are
               among the most diverse marine invertebrates. The adoption of a symbiotic lifestyle is one of their
               main environmental adaptations. Also, symbionts have a wide diversity of hosts and array of intra-
               specific association patterns. Because of the characteristics above, symbiotic crustaceans are ideal
               model systems to test the importance of environmental conditions in determining the evolution and
               adaptive significance of many behavioral traits. In this talk, I highlight studies in symbiotic crustaceans
               that have improved our understanding of the conditions explaining the behavioral diversity of marine
               invertebrates. Comparative studies have suggested that territorial behavior in symbiotic crabs has
               evolved in response to low host availability coupled with other host characteristics (i.e., small host
               size) that allow crabs to patrol and effectively defend their dwellings against intruders. Manipulative
               experiments have also corroborated the importance of host size in determining the successful
               defense of refuges through agonistic interactions. Resource limitation together with their economic
               defensibility drives the evolution of resource-monopolization behaviors as predicted by behavioral
               ecology theory. Life-history studies on symbiotic crustaceans have also serve as a guide to develop
               models predicting the evolution of mating systems. Recent experimental and descriptive studies have
               started to test the predictions of these models. Lastly, manipulative experiments conducted in the
               field and laboratory have demonstrated the importance of behavioral processes in determining the
               distribution of mobile marine invertebrates (even if they are small in size) in the natural environment.
               Future research lines with symbiotic crustaceans are proposed.


                                                                          37




oral.indd 37                                                                                                                09.8.11 9:06:41 AM
                                                           POSTER SESSION

                   SYMPOSIUM-RELATED CONTRIBUTED PAPERS
                   Symposium-related S1: Life History Migrations of Freshwater Shrimps: Ecological and
                       Adaptive Significance
                   [S1-P1] Life history of a land-locked prawn, Macrobrachium yui, in northern Laos
                            Oulaytham Lasasimma1), Pany Souliyamath2), Sayaka Ito3)
                              1)
                                Living Aquatic Resource Research Center, Vientiane, Lao PDR; 2) Na-Luang Stations, Luang Prabang
                              Province, Lao PDR; 3) Japan International Research Center for Agricultural Sciences, Japan

                   A land-locked prawn M. yui inhabits the mountainous areas of northern Laos patchily. Farmers
                   living in the river basin have understood that the prawn migrates from the main river to the cave
                   stream during rainy season and caught the prawn using the characteristics for obtaining cash income.
                   However, ecological characteristics of this species have been not reported in detail. In order to reveal
                   life history of the prawn M. yui, we performed the field research on breeding characteristics, life span
                   and migration pattern by sampling using traps monthly at fixed points in the Pho Stream, the cave
                   stream and the Xuang River. As a result, we estimated that life span of this species was 3 or 4 years
                   old. The size distributions of the prawn were significantly different among the waters year-around,
                   such as small size in the Xuang River, middle size in the Pho Stream and large size in the cave stream.
                   This indicates that the prawn migrates among the waters according to a growth. Although the seasonal
                   change of the gonadosomatic index showed that the peak of breeding season is August or September,
                   the prawn bred almost all year round because juvenile of the prawn appeared almost month by month.
                   The sampling by the drift net indicated that the prawn brood and hatch eggs in the cave stream. The
                   hatched larvae drift from the cave stream to the Xuang River after settling on the river bottom. Thus,
                   the cave stream is nursery ground for the larvae. On the basis of these results, we will discuss the
                   ecological characteristics of the prawn by comparison with those of amphidoromous prawn.



                   [S1-P2]     Comparative study of the biology of the prawns, Macrobrachium macrobra-
                             chion and Macrobrachium vollenhovenii in Epe Lagoon, Nigeria
                            Aderonke O. Lawal-Are, Hajarat Salihu
                              Department of Marine Sciences, University of Lagos, Nigeria

                   The size composition, growth, pattern, feeding habits and fecundity of 616 brackish water prawns,
                   Macrobrachium macrobrachium (Herklots, 1851) and Macrobrachium vollenhovenii (Herklots, 1857)
                   from Epe lagoon, Nigeria were examined. The total lengths of M. macrobrachium ranged from 6.6
                   to 11.4 cm and weighed between 1.7 and 14.0 g. Total lengths of M. vollenhovenii ranged from 4.9
                   to 13.4 cm and weighed between 2.0 and 34.0 g. Condition factor in M. macrobrachium ranged was
                   between 1.04 and 1.26 in M. vollenhovenii. M. vollenhovenii therefore had higher k-values. The two
                   prawn species fed on similar food items mainly phytoplankton (Cyclotella sp., Synedra sp., Tabellaria
                   sp.) and plant materials which suggested competition for food amongst these two species in the lagoon.
                   The sex ratio for M. macrobrachium was 1:03 (male/female) while that for M. vollenhovenii was 1:0.18n
                   showing that the males were predominant in both species. Fecundity in M. vollenhovenii ranged
                   between 4,315 and 30,661 eggs with a mean of 15,991 eggs. There was a slight correlation between
                   fecundity and total length (r = 0.580, n = 210, p < 0.05). There was no ripe female M. macrobrachium
                   obtained in the samples.




                                                                           38




symposium-related.indd 38                                                                                                          09.8.11 9:10:05 AM
                 Symposium-related S1: Life History Migrations of Freshwater Shrimps

                 [S1-P3] Habitat utilization of amphidromous freshwater shrimps (Atyidae) in agricul-
                        tural channels around the Furu River, Aichi, central Japan in relation to the ir-
                        rigation system
                            Kazuyoshi Nakata1), Masatoshi Denda1), Kunihiko Amano1), Junji Miwa1), Tatsuo Hamano2)
                              1)                                                                           2)
                                River Restoration Research Team, Public Works Research Institute, Japan;        Institute of Socio-Arts and
                              Sciences, The University of Tokushima, Japan

                 Most freshwater shrimps in Japan are amphidromous species. We have recently observed that large
                 numbers of amphidromous shrimps migrated into drainage channels of our research site. However,
                 these shrimps could not survive in some channels since they dried up during the non-irrigation period
                 (Nakata et al. in preparation). To effectively conserve migrating shrimp populations, we have tried
                 to clarify the habitat utilization patterns of the shrimps in relation to the irrigation system. In paddy
                 fields around the Furu River, irrigation water is supplied into the fields through water pipelines, which
                 is the typically used method in Japan, but after the irrigation period the water supply is stopped. The
                 drainage channels are supplied with water that overflows from the adjacent paddy fields and then flows
                 into the Furu River. Thus, we conducted a series of field surveys in eight channels during the irrigation
                 period (July and September) and non-irrigation period (October and November), to clarify the shrimp
                 distribution and the environmental factors affecting the channels. No shrimps were captured in all
                 channels in July, but two amphidromous shrimp species (mostly Caridina leucosticta) were collected
                 in seven channels in September. In October, water from the fields had disappeared in all channels. Four
                 channels, including one spring-fed channel, had almost dried up by November and the shrimps that
                 had migrated there were considered not to be able to survive. In contrast, many shrimps had migrated
                 into two spring-fed channels until November because spring water provided a stable and suitable
                 environment for shrimps. Only a few non-diadromous shrimps were observed in our surveys, which
                 indicate that they could not reproduce in the channels of our research site. These results indicate that
                 fluctuations in the water supply, which is determined by the irrigation system, affected the shrimp
                 species composition in the channels.




                                                                          39




symposium-related.indd 39                                                                                                                     09.8.11 9:10:05 AM
                   Symposium-related S3: Ecology and Behavior of Peracarids: Progress and Prospects

                   [S3-P1] Ecological analysis of amphipod assemblages in a polluted area of the coastal
                          southern Tyrrhenian Sea: the case of Baia Bay (Naples; Italy)
                            Loretta Lattanzi, Monica Targusi, Luisa Nicoletti
                              ISPRA – Institute for the Environmental Protection and Research, Italy

                   The purpose of this study was to analyze the spatial distribution of soft-bottom crustacean
                   amphipods occurred in a coastal area of the Southern Tyrrhenian Sea (Baia-Naples–Italy). This area
                   is characterized by different impact sources (e.g. heavy metals, PAH, presence of wrecks) and it is
                   included into the national interest reclaiming site “Litorale Domiziano Flegreo e Agro Aversano.”
                   Macrozoobenthos samplings were carried out in 17 stations at depths ranging from 3 to 30 m.
                   Granulometric and chemicals analyses of superficial sediments were also performed. Benthic data was
                   investigated with univariate (total number of individual, species richness and diversity indices) and
                   multivariate statistical (Cluster analysis) analyses. The analysis of amphipod assemblage highlighted
                   high values of species richness and diversity indices. Cluster analysis showed that both the depth and
                   the granulometric distribution of sediment were the chief factors in faunal similarity although the
                   chemical analyses confirmed widespread contamination of the area (high concentration of PAH and
                   high values of heavy metals such as mercury, copper and lead).




                   [S3-P2] Multiple plant traits that determine leaf palatability to detritivores: An investi-
                          gation using terrestrial isopods (Crustacea, Oniscidea)
                            Aline F. Quadros1), Martin Zimmer2), Paula B. Araujo1), Jair G. Kray3)
                              1)
                               Department of Zoology, Federal University of Rio Grande do Sul, Brazil; 2) Zoologisches Institut, Christian-
                              Albrechts-Universität zu Kiel, Germany; 3) Departamento de Botânica, Universidade Federal do Rio Grande do
                              Sul, Brazil

                   Detritivores influence leaf litter decomposition and nutrient cycling rates directly and indirectly.
                   Besides top-down regulation by predators, their populations may be bottom-up regulated by litter
                   biomass and also by litter chemistry. Therefore, their decisions towards specific leaf litter types
                   for feeding are likely to influence decomposition processes as well as their population dynamics.
                   We investigate how multiple leaf litter traits combine to determine palatability to detritivores. We
                   offered leaf litter from five Neotropical and five Paleartic trees to four woodlice species (Crinocheta):
                   Atlantoscia floridana (Philosciidae) and Balloniscus glaber (Balloniscidae), native to the neotropical
                   region and Porcellio scaber (Porcellionidae) and Philoscia muscorum (Philosciidae) from the Paleartic
                   region. Leaf litter was characterized regarding three classes of traits: structure-related traits (lignin,
                   cellulose, toughness and thickness), nutrient-related traits (Calcium, Nitrogen, Phosphorous and total
                   lipids) and secondary compounds (total amount and activity of phenolics). Both Neotropical and
                   Paleartic woodlice showed the same preference rank when offered a choice among the Paleartic leaves
                   while feeding preferences were slightly different when feeding on Neotropical litter. Rejection of
                   food by terrestrial isopods occurs when litter has: (1) high density of trichomes; (2) a combination of
                   leaf toughness >50 g mm-2 and C:N >25; and/or (3) a combination of N <2%, C:N >25 and cellulose
                   >30%. The preferred food is the one with N >2%, Ca >1%, thickness < 0.1 mm. Among plants that
                   fulfilled these last characteristics, neotropical isopods prefer softer leaves (lignin <20%) with C:N
                   ratio <20, while paleartic isopods showed preferences towards increased phenolic content (>2%).
                   We conclude that the mechanism of food recognition that determines leaf palatability to terrestrial
                   isopods is a conserved trait among phylogenetically and geographically distant species. These findings
                   have a predictive value as they may be used to predict woodlice function and importance in different
                   terrestrial ecosystems.



                                                                            40




symposium-related.indd 40                                                                                                                     09.8.11 9:10:05 AM
                 Symposium-related S4: Current Status of Fisheries and Biological Knowledge of Snow
                     and Tanner Crabs Genus Chionoecetes in the World
                 [S4-P1] The deep water crab fishery: Chionoecetes japonicus and Chionoecetes angula-
                        tus in the seas of the Russian Far East and the prospects for its development
                            Viktor. V. Miroshnikov1), Vasily. I. Sokolov2), Yuri V. Kucij3), Viktor V. Risovanny4)
                              1)
                                 Pacific Scientific and Research Institute of Fisheries and Oceanography, Russia; 2) Russian Federal Research
                              Institute of Fisheries and Oceanography (VNIRO), Russia; 3) ZAO Fishing Collective Vostok-1, Russia;
                              4)
                                 Federal Fisheries Agency of the Russian Federation, Russia

                 Deep water Chionoecetes japonicus and angulatus crab are the most numerous species of Brachyura
                 on the continental slope of the Russian Far Eastern seas. With the sharp decrease in the reserves of
                 shelf crabs in the Russian fishing zone, deep water Chionoecetes crab have become the most important
                 species in the crab fishing industry. TINRO Center is conducting studies of the bioresource pursuant
                 to a program of scientific research and since 2001 has been regularly involved in a joint program
                 on vessels owned by ZAO Fishing Collective Vostok-1. This article is based on data collected from
                 crab pot strings caught on vessels from ZAO Fishing Collective Vostok-1. A total of 40,000 strings
                 set in the Sea of Japan while fishing for Chionoecetes japonicus and more than 12,000 strings set in
                 the Sea of Okhotsk while fishing for Chionoecetes angulatus were analyzed. More than 9,000 daily
                 vessel reports from the Sea of Japan and 5,000 from the Sea of Okhotsk submitted to the Rybolovstvo
                 Database by other fishing vessels during the period 2003–2007 were also included in the analysis.
                 ZAO Fishing Collective Vostok-1 demonstrated the highest efficiency and profitability of all of the
                 Russian companies engaged in the deep water Chionoecetes crab fishery. This advantage was based
                 on the equipment used on the vessels and the fishing tactics employed by the company. Additionally,
                 the company introduced a year-round fishing program that resulted in expanded fishing areas in the
                 northern part of the Pacific Ocean and increased catch volumes. This is especially important in light of
                 the decrease in the reserves of crab on the continental shelf of the world’s oceans.



                 [S4-P2] Deep water Chionoecetes japonicus and Chionoecetes angulatus crabs in the Far
                        Eastern seas of Russia: their distribution, reserves and biological singularities
                            Viktor V. Miroshnikov1), Vasily I. Sokolov2)
                              1)
                                Pacific Scientific and Research Institute of Fisheries and Oceanography, Russia; 2) Russian Federal Research
                              Institute of Fisheries and Oceanography (VNIRO), Russia

                 Materials collected by scientific and commercial expeditions from 1991–2007 from TINRO Center
                 and ZAO Fishing Collective Vostok-1 were used to analyze the distribution and estimate the reserves
                 of deep water Chionoecetes crab in the seas of the Russian Far East. Maps of the distribution and
                 a calculation of the number of crabs were compiled using the spline approximation method using
                 the ChartMaster 3.1 GIS (VNIRO). Chionoecetes japonicus was observed at depths of 98–2,300 m
                 and Chionoecetes angulatus was observed at depths of 200–2,300 m. The distribution of the catches
                 of deep water crab at various depths demonstrated the existence of three main zones: the spawning
                 and molting zone for half-mature crabs at depths of less than 600 m, the commercial zone with a
                 predominance of commercial grade males and the feeding zone for recruits and immature male crab
                 at depths greater than 1500 m. The total number of Chionoecetes japonicus in all size and gender
                 groups in the northern part of the Sea of Japan was estimated to be 651 million. The total number of
                 Chionoecetes angulatus in the zones of the Sea of Okhotsk was 4,086 million crabs.




                                                                             41




symposium-related.indd 41                                                                                                                     09.8.11 9:10:06 AM
                   Symposium-related S9: Symbiosis in Crustaceans: Diversity and Evolutionary Trends

                   [S9-P1]     The biology of Argulus spp. (Crustacea: Branchiura: Argulidae) in Japan: a
                             review
                            Kazuya Nagasawa
                              Graduate School of Biosphere Science, Hiroshima University, Japan

                   Branchiurans of the genus Argulus Müller are usually ectoparasites of freshwater and marine fishes and
                   often cause disease problems in fish farms and aquaria. A total of nine species of the genus have been
                   reported from Japan: four species, A. japonicus Thiele, A. coregoni Thorell, A. americanus Wilson, and
                   A. lepidostei Kellicott or a related species, occur in fresh waters, whereas five, A. scutiformis Thiele,
                   A. caeus Wilson, A. onodai Tokioka, A. matsuii Shikama, and A. kusafugu Yamaguti and Yamasu, are
                   found in marine waters. Argulus americanus and A. lepidostei or a related species are not native to
                   Japan and were recovered from ornamental fishes that had been imported from the U.S.A. This paper
                   reviews various aspects of the biology of these nine branchiurans in Japan, focusing on A. japonicus
                   and A. coregoni, on which much information has been accumulated.




                   [S9-P2] Petrarca madreporae (Crustacea: Ascothoracida) collected alive from the deep-
                          water coral Madrepora oculata in Japan, with remarks on its early nauplius
                          larvae
                            Hiroyuki Tachikawa1), Mark J. Grygier2)
                              1)
                                   Coastal Branch of Natural History Museum and Institute, Chiba, Japan; 2) Lake Biwa Museum, Japan

                   In 1996, Grygier & Cairns reinterpreted grossly enlarged calices on colonies of deep-sea scleractinians
                   of the genus Madrepora as galls caused by ascothoracidan crustacean parasites of the family
                   Petrarcidae. In the same work, Grygier described a new species of this family, Petrarca madreporae,
                   based on specimens removed from such enlarged calices. Grygier & Cairns examined affected corals
                   from Hawaii, Japan, the South China Sea, Indonesia, and NW Australia, but most were dry, and
                   parasites were recovered from only one site in Indonesia. This fact caused one reviewer to question
                   whether P. madreporae is the primary cause of the deformity. Here we report the confirmatory
                   recovery of living specimens of P. madreporae from an enlarged calice of Madrepora oculata in Japan.
                   Two affected coral colonies, both examined alive on the day of collection, were taken on 11 March
                   2009 by a fisherman 25.7 km SE of Katsuura, Chiba Prefecture, at ca. 480 m depth. A fully living
                   colony ca. 130 x 120 x 45 mm in size had one enlarged calice (18.3 x 13.8 mm). Two specimens of P.
                   madreporae (4.3 and 5.2 mm long, both 2.3 mm wide) were found within the basal part of this calice
                   along with eggs that hatched into nauplius larvae. The first and second naupliar stages resembled those
                   of the confamilial ascothoracidan Zibrowia ? auriculata. The second colony, partly dead and ca. 260 x
                   190 x 70 mm in size, had three either slightly or considerably enlarged calices that were lacking coral
                   tissue at the time of collection and had only empty cavities inside. Photographs of the corals, their
                   enlarged calices, and the parasites, as well as illustrations of the nauplii, are presented here.




                                                                             42




symposium-related.indd 42                                                                                                             09.8.11 9:10:06 AM
                 Symposium-related S9: Symbiosis in Crustaceans: Diversity and Evolutionary Trends

                 [S9-P3] Seasonal changes of two ectosymbiotic worms Holtodrilus truncatus
                      (Branchiobdellida and Scutariella spp. (Temnocephalida) on the host shrimp
                       Neocaridina spp. from the Sugo River, western Japan
                            Nobuaki Niwa
                              Kobe Municipal Rokko Island Senior High School, Japan

                 Branchiobdellids (Annelida) and temnocephalids (Platyhelminthes) are both known to be ectsymbionts
                 of the decapod crustaceans. Their geographical distributions are separate, the former in the northern
                 and the latter in the southern hemisphere (Gelder, 1999). But, the Sugo River in western Japan is
                 one of the exceptional area, where the branchiobdellid Holtodrilus truncatus and the temnocephallid
                 Scutariella spp. were found together (Niwa and Ohtaka, 2006). Both species attached to the same host
                 shrimp, Neocaridina spp., which was supposed to be exotic. I investigated seasonal changes of their
                 mutual relations to the host shrimp there during 2004-2005, in the upstream (St. 1), midstream (St. 2)
                 and downstream (St. 3). The maximum number of attached individuals of a host shrimp ranged from
                 1-31 for H. truncatus, and from 2 -248 for Scutariella spp. thourghout the survey. The attached rate of H.
                 truncatus and Scutariella spp. to the host shrimps were 20.5 ± 14.0% (mean ± SD.) and 30.5 ± 18.5%
                 in St.1, 53.6 ± 27.7% and 44.5 ± 28.9% in St. 2, 29.3 ± 20.9% and 89.3 ± 22.4% in St. 3 throughout
                 the year, respectively: that of H. truncatus was higher in the midstream, on the other hand, that of
                 Scutariella spp. was much higer in the downstream. The rate of host shrimps that both ectosymbionts
                 attached and live together, was higher in the mid and downstream, being 8.4 ± 8.7% (mean ± SD.)
                 in St. 1, 22.4 ± 14.2% in St. 2, and 28.0 ± 21.5% in St. 3 throughout the year. The attached rate of H.
                 truncatus was high in spring, and decreased in July to September, then increased again afterward. As H.
                 trucatus cocoons were found throughout a year except February, this species breeds almost a year. This
                 is the first case where the coexisted branchiobdellids and temnocephalida was investigated.



                 [S9-P4] A taxonomic study on the genus Ceratothoa (Isopoda: Cymothoidae) parasitic
                        on fishes collected from Japan
                            Takeo Yamauchi
                              Toyama Institute of Health, Japan

                 The genus Ceratothoa (Isopoda: Cymothoidae) is composed of about 30 species that are parasitic on a
                 wide variety of fishes in the world. During a parasitological survey of fishes, six species of the genus
                 Ceratothoa were collected from Japanese waters: Ceratothoa curvicauda Nunomura from Decapterus
                 maruadsi (Temminck and Schlegel), Decapterus muroadsi (Temminck and Schlegel), Pseudocaranx
                 dentex (Bloch and Schneider), Decapterus macarellus (Cuvier), and Kaiwarinus equula (Temminck
                 and Schlegel); Ceratothoa oxyrrhynchaena (Koelbel) from Doederleinia berycoides (Hilgendorf),
                 Dentex tumifrons (Temminck and Schlegel), and Deutex abei Iwatsuki, Akazaki and Taniguchi;
                 Ceratothoa sp. near trigonocephala (Leach) from Kaiwarinus equula (Temminck and Schlegel) and
                 Pseudocaranx dentex (Bloch and Schneider); Ceratothoa sp. near imbricata (Fabricius) from Girella
                 puctata Gray; Ceratothoa sp.1 from Acropoma hanedai Matsubara; Ceratothoa verrucosa (Schioedte
                 and Meinert) from Pagrus major (Temminck and Schlegel) and Evynnis tumifrons (Temminck and
                 Schlegel). These six species of Ceratothoa are briefly reported herein.




                                                                          43




symposium-related.indd 43                                                                                                     09.8.11 9:10:06 AM
                   Symposium-related S9: Symbiosis in Crustaceans: Diversity and Evolutionary Trends

                   [S9-P5] The taxonomical importance of gnathiid larvae (Crustacea, Isopoda, Gnathi-
                          idae), ectoparasites of elasmobranches from the Ryukyu Archipelago
                            Yuzo Ota1), Euichi Hirose2)
                              1) Graduate School of Engineering and Science, University of the Ryukyus, Japan; 2) Faculty of Science, Uni-
                              versity of the Ryukyus, Japan

                   Gnathiids exhibit morphological differences among larvae, adult males, and adult females. Adults are
                   non-feeding and reproduce in the substrates such as sponges, dead corals, and tubes of polychaete
                   worms. Larvae are ectoparasites of fishes, sucking on their blood. After feeding, praniza larvae dwell
                   in the benthic substrata to rest and molt. Currently, over 180 species in 12 genera are known worldwide
                   but many undescribed species are thought to exist because of their small body (0.1-2.0 mm). Species
                   descriptions of gnathiids are traditionally based on the morphology of adult males, and it has been
                   supposed that the larval morphologies are not informative enough for species identification. Since
                                                                           2005, we have investigated gnathiid larvae that
                                                                           are ectoparasites of the elasmobranchs caught
                                                                           in the fishery off Okinawa Island, southwestern
                                                                           Japan. In our laboratory culture, some of the
                                                                           gnathiid larvae metamorphosed into adult males
                                                                           that were useful for specific identification and
                                                                           taxonomical description. As the results, we
                                                                           collected over 3,000 individuals of 8 types (=
                                                                           species) including 7 undescribed species of
                                                                           Gnathia spp. from 142 host elasmobranchs of 18
                                                                           species. The larva of each species was relatively
                                                                           large and has unique color pattern (Fig.). These
                                                                           larval features potentially distinguish the
                                                                           gnathiid species and enable us to make species
                                                                           identification of larvae for these species.

                                                                            Figure. Gnathiid larvae from elasmobranchs and their adult
                                                                            males raised in the laboratory culture.




                                                                            44




symposium-related.indd 44                                                                                                                    09.8.11 9:10:08 AM
                 Symposium-related S10: Reproductive Behavior of Decapod Crustaceans

                 [S10-P1] Function of waving display in mate acquisition in Ilyoplax pusilla (Brachyura,
                        Dotillidae)
                            Mari Ohata, Keiji Wada
                              Nara Women’s University, Japan

                 The dotillid crab Ilyoplax pusilla that lives on intertidal sandy mud flats has been known to perform
                 waving display (the rhythmic motion of chelipeds) during the reproductive season. Males of this
                 species direct intensive waving display at the female to attract her to his burrow when she approaches
                 him, suggesting that the directed waving display functions as courtship signal. Males also, however,
                 often perform waving that is not directed toward any particular individual. The function of undirected
                 waving display in the process of coupling is unclear. To clarify whether either of the sexes was more
                 often the target of undirected waving display, we conducted the field experiments that manipulated
                 neighbor’s sex. Waving frequency by males with male neighbors was significantly higher than that
                 of males with female neighbors. Waving frequency was correlated with the number of active male
                 neighbors but not with the number of active female neighbors. We also conducted the field experiment
                 that manipulated the abundance of waving males to test whether undirected waving display functions
                 in mate acquisition. We found that females preferred to approach groups that had more waving males.
                 These findings suggest that undirected waving display by male I. pusilla is activated through male to
                 male competition and functions as a long-range courtship signal.




                 [S10-P2] Male-male competition and the role of large cheliped in the hermit crab Pagu-
                        rus nigrofascia
                            Chiaki Yasuda, Yutaro Suzuki, Satoshi Wada
                              Faculty of Fisheries, Hokkaido University, Japan

                 Males of Pagurus hermit crabs show precopulatory mate guarding. While males engage in contest
                 competition for females with other males during guarding, they use large chelipeds as weapon. We
                 investigated (1) the factors determining the outcome of male-male competition and (2) the effect of
                 large cheliped on P. nigrofascia in competition for mates. We collected guarding pairs in the field and
                 used them in the following experiments. In Exp-1, we randomly assigned a pair and a male, which had
                 also guarded a female in the field, and placed them into small plastic containers. We observed male-
                 male competition for 15 minutes, and recorded the outcome of competition (100 replicates). Large
                 male advantage and owner advantage were found in P. nigrofascia. Guarding males flipped opponents
                 with large cheliped when the opponents approached. Winning percentage of each male also became
                 lower when females that he had guarded in the field molted later and when he had lost his large
                 cheliped. In Exp-2, to examine the effect of large cheliped, we chose two similar sized males, removed
                 large cheliped of one of them, and left each of them in an acrylic cup for more than 24 hours. We
                 then placed a mature female into either of the two cups. After all females were guarded, we observed
                 male competition for 30 minutes (79 replicates). Winning percentage of removed male was 4.8%,
                 confirming that the negative effect of cheliped removal on male-male competition in P. nigrofascia.
                 However, since percentage of large cheliped loss was relatively high (9.4%) in guarding males in the
                 field, such males might engage in hiding and fleeing from competitors during guarding to achieve
                 mating success. Large cheliped might play an important role in male-male competition of Pagurus
                 hermit crabs.




                                                                             45




symposium-related.indd 45                                                                                                 09.8.11 9:10:08 AM
                   Symposium-related S11: The New Perspective on Barnacle Research

                   [S11-P1] Do tiny males grow up? —Growth pattern and optimal resource allocation of
                          dwarf males of barnacle—
                            Sachi Yamaguchi1), Yuki Ozaki1), Yoichi Yusa2), Satoshi Takahashi1)
                              1)                                                                               2)
                               Graduate School of Humanities and Sciences, Nara Women’s University, Japan;          Department of Biology,
                              Nara Women’s University, Japan

                   Barnacles, marine crustaceans, have three sexual patterns: simultaneous hermaphroditism, dioecy and
                   androdioecy. In dioecy and androdioecy, large individuals (females and hermaphrodites, respectively)
                   are attached by tiny males (Darwin 1851). Barnacle males are very small compared to large individuals,
                   and they called “dwarf males.” Depending on species, some dwarf males grow up, others do not in
                   their life time. Males living in shallow sea are larger than ones living in deep sea (Pilsbry, 1908). Males
                   of androdioecious species tend to be larger than dioecious ones (Yusa and Yamato, unpublished). To
                   investigate which environmental conditions affect growth patterns of dwarf males of barnacles, we
                   make a resource allocation model of dwarf males. Inter-specific differences in body size of dwarf
                   males are caused by two factors: food efficiency (corresponding to water depth) and the amount of
                   sperm of large individual (if large individuals are hermaphrodites, this factor is positive, while it
                   equals 0 if they are female). Sperm competition among dwarf males and that among dwarf males and
                   large hermaphrodites are taken into account. Dwarf males grow up in food-rich environments, while
                   they do not grow at all in food-poor environments. Optimal resource allocation schedule between
                   reproduction and growth follows an ‘‘intermediate growth’’ (simultaneous growth and reproduction)
                   for dioecious species, in which sperm competition is not severe. On the other hand, it approaches
                   ‘‘bang-bang control’’ (switching from allocating all resources toward growth then to reproduction), as
                   sperm competition against surrounding large hermaphrodites is severer in androdioecious species. As
                   suggested by Yusa and Yamato, dwarf males’ body size in androdioesious species is larger than that in
                   dioecious species. Our mathematical model explains field data qualitatively.


                   [S11-P2] Stage-2 nauplius larvae of the symbiotic stalked barnacles Koleolepas and Het-
                          eralepas, and distinctive cirriped nauplii of unknown identity from Okinawan
                          plankton
                            Mark J. Grygier1), Yoichi Yusa2), Shigeyuki Yamato3), Jens Høeg4)
                              1)
                               Lake Biwa Museum, Japan; 2) Department of Biological Sciences, Nara Women’s University, Japan; 3) Seto
                              Marine Biological Laboratory, Kyoto University, Japan; 4) Department of Biology, University of Copenhagen,
                              Denmark

                   Larval series of many barnacles have been described and compared in a phylogenetic context, but the
                   larvae are essentially unknown for the six families of the order Heteralepadomorpha. Lacking shell
                   plates, their true position among the pedunculate Cirripedia is unclear. To try to remedy this, stage-2
                   nauplii of two representatives of the family Koleolepadidae (Koleolepas avis and K. cf. tinkeri) and
                   one species of Heteralepadidae (Heteralepas quadrata) from Japan were examined. In addition,
                   stage-2 nauplii evidently of stalked barnacles but not of any family with known larvae, and which are
                   among the most abundant cirriped larvae in the plankton at Sesoko Island, Okinawa, were examined.
                   The nauplii of Koleolepas and Heteralepas are surprisingly alike. They have similarly shaped cephalic
                   shields with no gland spines, and long, thorny dorsal thoracic spines and abdominal processes, the
                   latter sometimes being bifid apically. The long anterolateral horns are nearly perpendicular to the body
                   axis, with a curled tip and a single apical hair. The segmentation and armament of the appendages are
                   also nearly alike, although Heteralepas has an additional coxal element on the antenna and mandible.
                   These similarities may support the placement of these two families together in the same order. In
                   some respects resembling nauplii of Poecilasmatidae, they also closely match an unidentified stage-6
                   nauplius described by Grygier in 1996 from Osaka Bay except in horn length; in particular, these all
                   have multisegmented mandibular exopods, unlike poecilasmatids. The Okinawan nauplii agree with
                   those of the Poecilasmatidae in cephalic shield shape and armament, but differ from them and other
                   long-spined cirriped nauplii in the pair of large furcal spines arising directly from the body with no
                   long abdominal process. They are most similar to Lang’s unidentified “nauplius” from off South
                   Carolina.


                                                                          46




symposium-related.indd 46                                                                                                                    09.8.11 9:10:08 AM
                 Symposium-related S11: The New Perspective on Barnacle Research

                 [S11-P3] Dwarf males in symbiotic pedunculate barnacles
                            Shigeyuki Yamato1), Yoichi Yusa2), Katsumi Miyazaki1)
                              1)
                                   Seto Marine Biological Laboratory, Kyoto University, Japan; 2) Nara Women’s University, Japan

                 The majority of barnacles are hermaphrodites, but there are other types of sexuality: androdioecy
                 (large hermaphrodites and dwarf males), and dioecy (large females and dwarf males). When males
                 appear, they are always tiny and attached to either large hermaphrodites or large females. Recent
                 theoretical studies have suggested that reduced mating group size is an important factor for the
                 evolution of sexuality and occurrence of dwarf males. Mating group size tends to be reduced in deep-
                 sea or symbiotic habitats. Dwarf males have been found mainly from scalpellids, most of which live in
                 deep-sea; however, males of other pedunculate barnacles have been scarcely reported. We have found
                 dwarf males from various groups of pedunculate barnacles; especially, in symbiotic species, such as
                 Koleolepas (under sea anemones), Paralepas (on gastropods), Octolasmis (on carapace of crabs),
                 Alepas (on jellyfish). We investigated the characteristics of these dwarf males, comparing with the
                 mating group size and sexuality of large individuals. There were various degree of dwarfing; reduction
                 of body size, degeneration of calcareous plates and cirri. Dwarf males in Octolasmis and Alepas have
                 almost the same morphology as large individuals, and may become hermaphrodites later, as in the
                 “apertural male” reported in the balanomoroph Chelonibia. In summary, symbiotic condition limits the
                 number of large individuals living on the host and reduces their mating group size, which determines
                 the occurrence and condition of dwarf males. More dwarf males could be found in such habitats.




                 [S11-P4] Sperm competition among dwarf males of Scalpellum stearnsii (Cirripedia:
                        Lepadomorpha) as revealed by microsatellite markers
                            Yuki Ozaki, Shin-ichi Iwaguchi, Yoichi Yusa
                              Department of Biological Sciences, Faculty of Science, Nara Women’s University, Japan

                 Dwarf males are extremely tiny (<50% of female body length) males known in barnacles, angler fish,
                 spiders, etc. They are expected to evolve when their fitness is comparable to that of larger males, but
                 no studies have addressed their fertilization success, due to lack of adequate molecular tools. In the
                 deep-sea pedunculate barnacle Scalpellum stearnsii Pilsbry (Cirripedia: Lepadomorpha: Scalpellidae),
                 up to 35 dwarf males attach to the female, and each settles into a “receptacle” (small cavity) lined
                 along the occludent margin of the female. The distribution of males is even between left and right
                 sides but highly skewed towards lower occludent margin (nearer the female gonopores). These
                 suggest that there is variation among receptacles to attain higher fertilization success, and males may
                 compete to settle and occupy more suitable receptacles. We studied fertilization success of each male
                 by determining paternity of embryos using microsatellite markers. We collected female S. stearnsii
                 off Satsuma Peninsula, southern Japan, and dissected out dwarf males and embryos after recording
                 their positions. We also developed microsatellite markers, and decided genotypes of females, dwarf
                 males and embryos to identify the genetic father of each embryo. The paternity analysis indicated
                 that embryos tended to be fertilized by males on the same (left or right) side of the female. Moreover,
                 there was a negative relationship between fertilization success of a male and its distance from the
                 lowest occludent margin. These results suggest that males can fertilize only eggs near them, and males
                 that settle nearer the female gonopores attain higher fertilization success. However, male size had no
                 significant relationship with the fertilization success. Therefore, larvae that will become males should
                 settle as early as possible to occupy suitable receptacles instead of growing large. This might be an
                 evolutionary force that has promoted male dwarfing.




                                                                               47




symposium-related.indd 47                                                                                                          09.8.11 9:10:08 AM
                   Symposium-related S12: Phylogeography and Population Genetics in Decapod
                   Crustacea
                   [S12-P1] Genetic diversity and population structure of Pronghorn spiny lobster Panuli-
                          rus penicillatus in the Ryukyu Archipelago based on mitochondrial DNA control
                          region sequences
                            Fadry Muhamad1), Hideyuki Imai2)
                              1)                                                                               2)
                               Graduate School of Science and Engineering, University of the Ryukyus, Japan;        Faculty of Science,
                              University of the Ryukyus, Japan

                   The mithochondrial DNA (mtDNA) control region was sequenced to examine the genetic diversity and
                   population structure of Panulirus penicillatus. In total, 458 nucleotide sequences were obtained from
                   162 specimens of P. penicillatus from Amamiohshima Island, Okinawajima Island and Ishigakijima
                   Island, in which 192 variable sites and 159 haplotypes were identified. The haplotype and nucleotide
                   diversities at the three sample locations were high (h = 0.9992 and π = 0.0372 in Amamiohshima
                   Island; h = 0.9994 and π = 0.0390 in Okinawajima Island and h = 1.0000 and π = 0.0332 in
                   Ishigakijima Island). Mismatch distribution analyses was used to evaluate possible historical events
                   of population growth and decline (τ = 18.5170 in Amamiohshima Island; τ = 17.7150 in Okinawajima
                   Island and τ = 9.5350 in Ishigakijima Island). Genetic diversity was high for each of these localities.
                   Pairwise Fst values showed no significant genetic differences among three localities. These results
                   suggest that Kuroshio current and its counter current promote gene flow in Ryukyu Archipelago.




                                                                       48




symposium-related.indd 48                                                                                                                 09.8.11 9:10:08 AM
                  Symposium-related S13: Biology of Anomura III

                  [S13-P1] Population features and breeding season of the land hermit crab Coenobita
                         scaevola (Forskål, 1775) (Anomura, Coenobitidae) from Wadi El-Gemal, South
                         Red Sea
                            Wafaa S. Sallam1) and Fernando L. Mantelatto2)*
                              1)
                                Department of Marine Science, Suez Canal University, Egypt; 2) Laboratory of Bioecology and Crustacean
                              Systematics, Department of Biology, FFCLRP – University of São Paulo (USP), Brazil *Financial support:
                              CNPq

                  Population dynamics of the land hermit crab Coenobita scaevola was evaluated focusing on size
                  structure, sex ratio and breeding season. Specimens were randomly collected on a monthly basis from
                  January to December 2007 at Wadi El-Gemal, Marsa Alam, South Red Sea. In total, 1088 crabs were
                  obtained, of which 496 (45.6%) were males, 557 (51.2%) non-ovigerous females, and 35 (3.2%)
                  ovigerous females. The overall size frequency distribution was unimodal for males, non-ovigerous
                  females and ovigerous females. The overall sex ratio (1:1.9) was in favor of females. The population
                  profiles of C. scaevola show some peculiarities when compared with congenerics and other diogenids.
                  In particular, the low reproductive rate and early maturation of females inspire caution regarding
                  maintaining this population, and can be hypothesized to minimize costs during life cycle.




                  [S13-P2] Life history and shell utilization patterns of the two sympatric Pagurus species (P. ni-
                          grofascia and P. minutes), especially with embryonic diapause of P. nigrofascia
                            Shinji Mishima1), Yasuhisa Henmi2)
                              1)                             2)
                               Junshin High School, Japan;        Aitsu Marine Station, Center for Marine Environment Studies, Kumamoto
                              University, Japan

                  Life history, vertical distribution and shell utilization patterns of the sympatric intertidal hermit
                  crabs (Pagurus nigrofascia and P. minutus) were investigated in a boulder shore in Fukuoka, Japan,
                  using the line transect samplings of over three years. Moreover, in the laboratory, the influences of
                  light and temperature to the embryos diapause termination were examined experimentally. In Japan,
                  P. nigrofascia inhabits some intertidal boulder shores, but the habitat is extremely restricted. In the
                  spring, they widely distributed throughout the intertidal area but moved under some boulders in the
                  upper intertidal area in the summer and to the middle intertidal area in the autumn. In the winter, most
                  were collected in the lower intertidal area, as many have been moving into the subtidal area. They
                  utilized various kinds of shells. Most females matured in 2-3 years and produced a brood in March
                  and released larvae in December after an extremely long incubation period of 9 months. From March
                  to October, the embryos were in diapause. In the laboratory experiments, we showed that the embryos
                  diapause termination was controlled by temperature. On the other hand, P. minutus is one of the most
                  common hermit crab in Japan, mainly inhabits the tidal flat. Throughout the year, they were found
                  in the lower area of P. nigrofascia habitat and most moved into the subtidal area in winter. Females
                  matured in 1-2 years and produced several broods from October to March. They mainly utilized
                  Batillaria spp. shells. The egg number per brood and egg size were almost similar between the two
                  species and the reproductive effort was much smaller in P. nigrofascia. There may be several factors
                  which enable the coexistence of P. nigrofascia and P. minutus; e.g. the inhabit in severe upper intertidal
                  area, the embryos diapause and the utilization of various shells.




                                                                             49




symposium-related.indd 49                                                                                                                 09.8.11 9:10:09 AM
                   Symposium-related S13: Biology of Anomura III

                   [S13-P3] Allogalathea elegans (Decapoda, Galatheidae): a monotypic genus?
                            Patricia Cabezas1), Enrique Macpherson2), Annie Machordom1)
                              1)                                                      2)
                                Museo Nacional de Ciencias Naturales (CSIC), Spain;        Centro de Estudios Avanzados de Blanes (CSIC),
                              Spain

                   The genus Allogalathea was described to accommodate the single species Allogalathea elegans. Such
                   species shows a wide distribution across the Indo-Pacific Ocean and is characterized by living in as-
                   sociation with crinoids and exhibit very different and conspicuous colourations. The different col-
                   ourations and the variability in some carapace and pereopod characters raise the question about the
                   monotypy of the genus. In order to clarify if the species Allogalathea elegans constitutes a monotypic
                   genus, the mitochondrial gene cytochrome oxidase I (COI) was analyzed. Preliminary results support
                   the monophyly of the genus and point out the existence of four divergent and deep clades with a pair-
                   wise distance between 10.49–15.06%. These divergences suggest the existence of some cryptic species
                   into the genus Allogalathea that can be distinguished by subtle morphological characters. Seemingly,
                   the evolution of the colour pattern and not the colouration itself might be related to the phylogenetic
                   relationships within the different clades.




                   [S13-P4] Peripatric speciation drives diversification and distributional pattern of reef
                          hermit crabs (Decapoda: Diogenidae: Calcinus)
                            Maria Celia (Machel) Malay, Gustav Paulay
                              Florida Museum of Natural History, University of Florida, USA

                   In this paper we examine patterns of speciation and distribution in a typical reef-associated clade –
                   the diverse and colorful Calcinus hermit crabs – to address the origin of tropical marine diversity.
                   What mechanisms of speciation gave rise to species? What role does does ecology play in speciation?
                   How is species richness distributed and what accounts for this pattern? We sequenced ~90% of 56
                   putative species, including 9 undescribed, ‘cryptic’ taxa, and mapped their distributions. Speciation
                   is largely peripatric at remote locations. Allopatric species pairs are younger than sympatric ones,
                   suggesting >2 million years are needed for secondary sympatry. Substantial niche conservatism is
                   evident within clades, as well as a few major ecological shifts between sister species. Color patterns
                   follow species boundaries and evolve rapidly, suggesting a role in species recognition or separation.
                   Most species prefer and several are restricted to oceanic areas, giving rise to an ocean-centric diversity
                   pattern. Unlike in most taxa, diversity peaks in the west-central oceanic Pacific, rather than in the
                   Indo-Malayan “diversity center.” Calcinus speciation patterns do not match well-worn models put
                   forth to explain the origin of Indo-West Pacific diversity, but underscore the complexity of marine
                   diversification.




                                                                           50




symposium-related.indd 50                                                                                                                   09.8.11 9:10:09 AM
                 Symposium-related S13: Biology of Anomura III

                 [S13-P5] Population genetic structure of a common Japanese intertidal hermit crab
                        Pagurus filholi (Crustacea: Decapoda: Anomura: Paguridae) throughout the
                        range, inferred from cytochrome oxidase subunit I sequences
                            Kaoru Suzuki1), Akira Asakura2), Mana Nakajima1), Ryoko D. Segawa3), Tadashi Aotsuka3)
                              1)
                               Department of Biological Science, Tokyo Metropolitan University, Japan; 2) Department of Zoology, Natural
                              History Museum & Institute, Chiba, Japan; 3) Department of Biology, Graduate School of Science, Tokyo
                              Metropolitan University, Japan

                 Pagurus filholi is a common intertidal hermit crab inhabiting wave-exposed rocky shores in Japanese
                 Archipelago from Hokkaido to Kyushu, and Korea and Russia. Into this region, two large oceanic
                 currents, a warm tropical oceanic current, Kuroshio, and a cold subarctic oceanic current, Oyashio,
                 flow, which have strong influences on both terrestrial and marine climates and biota. Behavior and
                 ecology of this species were intensively studied in several localities in Japan. These studies have
                 revealed noticeable geographical differences between Oyashio area and Kuroshio area in various
                 aspects for reproductive characteristics. In the population of the Oyashio area, the reproduction
                 occurs in summer, while in those of the Kuroshio area, the reproduction occurs in winter. Males in
                 populations of the Oyashio area are more aggressive and more intensively chase to females than those
                 in the Kuroshio area. An alternative strategy for copulating with a female by small males is observed
                 only in the Oyashio area. To test genetic differentiation between the populations discriminated by these
                 reproductive and behavioral characteritics, we examined sequence variation from the mitochondrial
                 cytochrome oxidase I (COI) gene region for the samples collected throughout the range of distribution.
                 However, contrary to our expectation, no genetic differentiation was detected among populations
                 in different areas. Those differences therefore might not be genetically determined but induced by
                 environmental factors such as water temperature. However, we examined only COI of mtDNA for
                 161 individuals from 11 localities. So, further study is needed, for example, for more samples from
                 more localities, examination of nuclear loci, microsatellite marker analysis, and experiment to test
                 plasticity in mating behavior and reproductive season induced by environmental factors such as water
                 temperature.


                 [S13-P6] Morphology of the spermatophore of the intertidal hermit crab Clibanarius
                        sclopetarius Herbst, 1876 (Anomura, Diogenidae)
                            Fernando L. Mantelatto, Nathalia M. Santos
                              Laboratory of Bioecology and Crustacean Systematics, Department of Biology, Faculty of Philosophy, Sciences
                              and Letters of Ribeirão Preto (FFCLRP), University of São Paulo (USP), Brazil Financial support: CNPq (Proc.
                              301350/2007-5)

                 The immobile sperm of the Decapoda are transferred to females through the spermatophores. These
                 are covered by membrane, and have mucopolysaccharides for sperm protection against desiccation
                 and action of microorganisms. These structures present a high morphological variability among the
                 Decapods, being tripartite in hermit crabs. The morphology study of spermatophores has been used in
                 taxonomy and also to better understanding the phylogenetics relations between the species of hermit
                 crabs. In the family Diogenidae, Clibanarius sclopetarius has few studies about its reproductive
                 biology, being necessary the description of this structure to its better comprehension and contextualize
                 with others congeners species, whose spermatophores were described. For this, 20 males individuals
                 were collected in the intertidal region of the Araçá mangrove, São Sebastião (São Paulo – Brazil),
                 and had their reproductives organs fixed in 80% ethanol. Espermatophores were retreat of the distal
                 region of the vas deferens and analyzed with optical microscopy and scanning electron microscopy.
                 The spermatophore found for the species just has an ampulla to store spermatozoon. This pack
                 has sides projections that join together the next spermatophore. It has still, a lateral ridge in the
                 apical axis, responsible for opening the release of spermatozoon. Clibanarius sclopetarius presents
                 different spermatophores from the morphological pattern described for the genus (e.g. C. corallinus,
                 C. erythropus, and C. virescens), owning similarity with the pattern described to C. vittatus and C.
                 longitarsus. Our results reinforce the necessity of a phylogenetic revision away these taxa.




                                                                            51




symposium-related.indd 51                                                                                                                    09.8.11 9:10:09 AM
                   Symposium-related S13: Biology of Anomura III

                   [S13-P7] Indirect female choice mediated by sexual pheromone in the hermit crab
                          Pagurus filholi
                            Saori Okamura, Seiji Goshima
                              Faculty of Fisheries Sciences, Hokkaido University, Japan

                   Males of the hermit crab Pagurus filholi perform precopulatory guarding behavior in which males
                   grasp the shells of ripe females with their left cheliped until copulation. Solitary males often show
                   aggressive behavior to take away the guarded females. Males behave coercively while guarding
                   females, so direct mate choice by females appears to be difficult in such situation. We examined a
                   possible indirect female choice of the hermit crab by several experiments. Males were attached a shell
                   by their left cheliped with bonding glue look like guarding pairs (fake guarding pairs). The shells were
                   filled with soaked cotton containing each of seawater or pheromone water. Even the fake guarding
                   pair with only seawater caused male-male combat at 57% of the trials, while with pheromone water
                   combats occurred at 90%. Mean duration of male-male combat was significantly longer in the trials
                   with dropping seawater containing pheromone than those without pheromone. These results suggest
                   guarding pairs themselves cause male-male combat, males rely on visual stimulation to recognize
                   guarding pairs, female sexual pheromone has further significant function to recognize guarding pairs
                   and intensify male-male combat, and females release sexual pheromone while they are guarded. As a
                   result of the combat, the larger male ended up guarding a female. Therefore, it is highly suggested that
                   females choose males indirectly by exploiting male-male competition induced by sexual pheromone
                   under male coercive behavior of precopulatory mate guarding.




                                                                            52




symposium-related.indd 52                                                                                                     09.8.11 9:10:09 AM
                 Symposium-related E: Conservation Biology of Freshwater Crayfishes - New Challenge
                     Starting from Japan, Eastern Asia
                 [SE-P1] A morphological variety of fresh-water palaemonid shrimps (Crustacea: Decap-
                        oda: Palaemonidae) of Sakhalin Island and adjacent territories
                            V. S. Labay1), E. A. Barabanshikov2)
                              1)
                                   Sakhalin Research Fishery Institute, Russia; 2) Pacific Research Fishery Institute, Russia

                 For the first time the detailed morphological analysis of shrimps of family Palaemonidae of Sakhalin
                 Island carried out. For comparison shrimps from fresh waters of Primorski Region (Russia) and
                 Hokkaido Island (Japan) are used. The analysis is carried out on a structure of rostrum, antennal scale,
                 mandible, pereiopod of the first and second pairs, abdominal appendages of the first and second pairs,
                 telson. In total 16 attributes are used. Palaemon macrodactylus (Primorski Region) is most detached
                 from other species by results of the cluster analysis. Significant distinctions characterize Palaemon
                 modestus (Primorski Region). Lake and river forms of P. modestus have significant distinctions to
                 all attributes practically. Distinctions between them are on a subspecies or even a species level and
                 acknowledgement by the genetic analysis demand. Palaemonetes sinensis (Primorski Region) is closest
                 to a group Palaemon paucidens. Its difference from last are defined as a standard attribute (absence a
                 pulp of mandible), and a structure of a molar of right mandible. Individuals of P. sinensis from fresh
                 waters of Sakhalin Island are concern to P. paucidens on the majority of attributes. Absence at them a
                 pulp of mandible probably is a natural mutation. Individuals from Russian Island (Primorski Region)
                 are most detached in a group P. paucidens. The greatest similarity characterizes individuals from
                 southern Sakhalin and northern Japan. P. paucidens are divided by three forms: lake, river and shrimps
                 from Ubaranai-dam (Hokkaido Island). Shrimps from Ubaranai-dam differ from other P. paucidens also
                 in the sizes at which there comes a stage “female.”




                                                                                  53




symposium-related.indd 53                                                                                                      09.8.11 9:10:10 AM
                    GENERAL CONTRIBUTED PAPERS


                    [GP-1] Comparison of genetic population structures between the landlocked shrimp,
                           Neocaridina denticulata denticulata, and the amphidromous shrimp, Caridina
                           leucosticta (Decapoda: Atyidae)
                            Junta Fujita, Kouji Nakayama, Yoshiaki Kai, Masahiro Ueno, Yoh Yamashita
                               Field Science Education and Reserch Center, Kyoto University, Japan

                    Neocaridina denticulata denticulata and Caridina leucosticta are common freshwater shrimps widely
                    distributed in western Japan. They are closely related and have similar distributional patterns, the
                    former is characterized by a landlocked life history and the latter an amphidromous one, suggesting
                    that their genetic population structures are different due to different dispersal abilities. However, few
                    comparative studies have been conducted among freshwater shrimps with different life histories. We
                    examined the mitochondrial DNA (mtDNA) sequence variations of the NADH dehydrogenase subunit
                    2 and 5 (ND2 and ND5, respectively) genes in 180 individuals of N. d. denticulata from nine localities
                    and 160 individuals of C. leucosticta from eight localities except Nansei islands. The phylogenetic tree
                    obtained by the neighbor joining method showed several distinct clades roughly corresponding to the
                    local populations within N. d. denticulata, but no distinct clades within C. leucosticta. Pairwise FST
                    and AMOVA also indicated a significantly strong genetic differentiation among populations of N. d.
                    denticulata, but little genetic differentiation if any among populations of C. leucosticta. These results
                    suggest the absence of gene flow between local populations in N. d. denticulata, but high gene flow
                    in C. leucosticta due to its dispersal in the sea. Therefore, the difference in the population structure
                    characteristics in the freshwater shrimp is considered to be strongly affected by their life histories.




                    [GP-2] Geographical variation of mtDNA and larval development in relation to habitat
                           utilization by the freshwater palaemonid prawn, Palaemon paucidens
                            Yoh Usami, Masashi Yokota, Carlos A Strüssmann, Seiichi Watanabe
                               Tokyo University of Marine Science and Technology, Japan

                    Palaemon paucidens, the only freshwater species in the genus Palaemon, is widely distributed in East
                    Asia. Our previous research has shown that P. paucidens is particularly abundant in the downstream
                    to midstream areas of rivers and in lakes and swamps far away from the sea and that there appears
                    to be distinct riverine and lacustrine populations. Limited genetic information on isozymes seems to
                    support this habitat separation but neither a genetic analysis using mtDNA RFLP nor a comparison
                    of the larval development between these two forms has ever been conducted. This study examined
                    the geographical variation of mtDNA and larval development in relation to habitat utilization by P.
                    paucidens. Sampling was carried out in central part of Honshu, Japan in total of 214 inland water
                    bodies. Collections were made using a scoop net during May-September from 2004 to 2008. Samples
                    from 15 sites in Japan, and the site in Korea were analyzed for mtDNA polymorphism in the COI
                    region (556bp) using DNA sequence data. Newly hatched larvae for the developmental analysis were
                    obtained from berried females collected in the wild and reared under similar rearing conditions. The
                    mtDNA analysis allowed a clear separation of populations according to habitat utilization. A common
                    haplotype was found among the 7 riverine populations indicating the occurrence of genetic exchange
                    between neighboring populations. In contrast, a single, characteristic haplotype was detected in each of
                    the 8 lacustrine populations, suggesting considerable genetic isolation. Specimens from representative
                    riverine and lacustrine populations showed marked differences in larval development. Prawns from
                    riverine populations had more larval instars (13) and were amphidromous whereas lacustrine prawns
                    had a short larval period (6-8 instars). The information obtained in this investigation provides the basis
                    for the implementation of habitat and genetic resource conservation programs for Palaemonid prawns.




                                                                            54




General (poster).indd 54                                                                                                         09.8.11 9:10:35 AM
                  General Contributed Papers (posters)

                  [GP-3] Suspected invasion of freshwater atyid shrimp from China into Japan revealed
                         by mitochondrial DNA analysis
                           Hiroko Tohyama1), Ikeda Minoru1), Nobuaki Niwa2), Akifumi Ohtaka3), Yongde Cui4), Hong-
                           Zhu Wang4), Machiko Nishino5)
                             1)
                               Field Science Center, Graduate School of Agricultural Science, Tohoku University, Japan; 2) Roko Island
                             High School, Japan; 3) Hirosaki University, Japan; 4) Chinese Academy of Sciense; 5) Lake Biwa Environmental
                             Research Institute, Japan

                  Recent invasion of taxonomically unsettled atyid shrimp Neocaridina spp. from China into Japan
                  has been suspected through the import as fishing bait. This suspicion is founded on the fact that
                  considerable numbers of the symbiotic branchiobdellidan (Holtodrilus truncates) known only from
                  China have been recorded on the shrimps in central Japan. To elucidate this suspicion, we collected
                  214 shrimp specimens from Japan (23 localities) and 46 ones from China (six localities in Henan,
                  Gwangdong, and Liaoning Provinces including a storage house where the shrimps were collected from
                  anonymous sites in China) and sequenced their partial CO I (522bp) and 16SrRNA (473bp) genes of
                  the mtDNA. The phylogenetic tree based on all 109 combined haplotypes using K2P and NJ methods
                  showed two major clades (I and II). These two clades were clearly distinguishable by one indel site
                  of 16SrRNA. Clade I was composed of the haplotypes detected only from Japan, while Clade II was
                  composed of those observed from both countries. Clade II included the haplotypes with identical or
                  few nucleotide differences between Japan and China. This phylogeographic information indicates that
                  Clades I and II are assigned to the indigenous lineage in Japan (i.e., N. denticulata denticulate) and the
                  exotic ones from China (e.g., N. heteropoda, N. palmate or related species), respectively. From these
                  aspects, we would have to conclude that invasion of Neocaridina spp. from China into Japan has really
                  occurred. In four localities of Japan, the two clades were observed sympatrically. In such localities,
                  there is concern that genetic pollution through hybridization or introgression between indigenous and
                  exotic populations may occur.



                  [GP-4]    On the taxonomic status of Potimirim brasiliana Villalobos, 1959 (Decapoda:
                           Atyidae) using morphological and molecular analysis
                           Lucas S. Torati, Fernando L Mantelatto
                             Laboratory of Bioecology and Crustacean Systematics, Department of Biology, Faculty of Philosophy, Sciences
                             and Letters of Ribeirão Preto (FFCLRP), University of São Paulo (USP), Program of Post-Graduation on
                             Comparative Biology

                  Potimirim brasiliana Villalobos (1959) is a freshwater shrimp described for Angra dos Reis, RJ, Brazil.
                  The original description is rich in details but lacked comparisons with Potimirim glabra (Kingsley,
                  1878), a close related species described for the Pacific slope of Nicaragua. Both species live at similar
                  niches in coastal rivers of the Neotropical region. Smalley (1963) proposed their synonymy, what
                  implied the occurrence of P. glabra in the Pacific and Atlantic and Pacific coasts of Central America,
                  Antilles and Brazil. The name P. brasiliana is currently invalid, but at this time no consensus exists
                  on the taxonomic status of the species. Considering this doubtful scenario, the present study aimed
                  to better elucidate the taxonomic status of P. brasiliana based on morphological and molecular (16S
                  rRNA) data. The external morphology of specimens from the Pacific slopes of Panama, Costa Rica and
                  Mexico were compared to those from Brazil (SC, PR, SP, RJ and BA States, including type-locality of P.
                  brasiliana). Despite the well-known morphological similarities between them, such as the presence of
                  epipods on the fourth pairs of pereopods and the “U”-shaped entrance on the margin of the appendix
                  masculina, some characteristics of the rostrum, pereopods, preanal carena and appendix masculina
                  are considered to distinguish them. These morphological evidences were also strongly supported by
                  a molecular cladistic phylogeny for the genus, which shows P. brasiliana as a distinct lineage. These
                  evidences together imply the recovery of the name P. brasiliana to those populations occurring in
                  Brazil.




                                                                           55




General (poster).indd 55                                                                                                                    09.8.11 9:10:35 AM
                    General Contributed Papers (posters)

                    [GP-5] Stenopodidean shrimps of the “Taiwan” cruises
                           Chien-Lin Chen, Tin-Yam Chan
                              Institude of Marine Biology, National Taiwan Ocean University, Taiwan

                    Stenopodidean shrimps collected by “Taiwan 2000-2006” consisted of eight species in five genera.
                    They are Engystenopus palmipes Alcock & Anderson, 1894, Globospongicola spinulatus Komai &
                    Saito, 2006, Spongicola andamanicus Alcock, 1901, S. goyi Saito & Komai, 2008, S. levigatus Hayashi
                    & Ogawa, 1987, Spongicoloides iheyaensis Saito, Tsuchida & Yamamoto, 2006, Stenopus hispidus
                    (Olivier, 1811) and a new species of Stenopus. All species except Stenopus hispidus are new records
                    of Taiwan. The new Stenopus species most closely resembles S. hispidus but differs chiefly by having
                    fewer spines on the third pereiopod.




                    [GP-6] Lobsters of the “PANGLAO 2004” Philippines expedition
                           Chih-Kuei Kao, Tin-Yam Chan
                              Institute of Marine Biology, National Taiwan Ocean University, Taiwan

                    The international biodiversity survey “PANGLAO 2004” at the Bohol Sea, the Phillippines had
                    collected 13 genera and 22 species of lobsters. Amongst them 2 are new to sciences and 5 are new
                    records for the Philippines. Several species, such as Palinustus waguensis, Enoplometopus crosnieri,
                    Petrarctus veligar, were though to be very rare but found to be rather common there. All the species
                    have color photographs on fresh specimens. Preliminary results of the lobsters collected from the
                    following up deep-sea cruises “PANGLAO 2005” and “AURORA 2007” in the Philippines are also
                    presented.




                                                                            56




General (poster).indd 56                                                                                                   09.8.11 9:10:36 AM
                  General Contributed Papers (posters)

                  [GP-7]    Report on some caridean and stenopodidean shrimps (Crustacea: Decapoda:
                           Caridea) from Indo-Pacific Ocean and Atlantic off Brazil
                           Xinzheng Li 1), Règis Cleva2)
                             1)                                                               2)
                               Institute of Oceanology, Chinese Academy of Sciences, China;        Département Milieux et Peuplements
                             aquatiques, Muséum national d’Histoire naturelle, France

                  Based on the material deposited in the Muséum national d’Histoire naturelle, Paris, collected mainly
                  from the Indo-West Pacific Ocean, the present paper reports 88 caridean and stenopodidean shrimp
                  species of five families 25 genera. They belong respectively to Caridean: Campylonotoidea - Ba-
                  thypalaemonellidae, one genue one species, Palaemonoidea - Anchistioididae, one genus two species,
                  Palaemonidae - Palaemoninae, three genera six species, Pontoniinae, 18 genera 76 species, in which,
                  19 are new species; Stenopodidea: Spongicolidae, one genus two species, Stenopodidae, one genus
                  one species. Allmost all the specimens were collected from the Indo-Pacific localities respectively:
                  Madagascar, La Réunion, Philipplines, Indonesia, Papua New Guinea, Micronesia (Chuuk Is.),
                  Solomon Is., New Caledonia, Loyalty Is., Vanuatu, Futuna Is., Fiji, Polynesia (Tuamotu Is.), only
                  one ovigerous female specimen of Periclimenaeus pearsei (Schmitt, 1932) was collected from South
                  Atlantic off Brazil. The new species are described and illustrated.




                  [GP-8] Molecular systematics of peppermint and cleaner shrimps: genera Lysmata and
                         Exhippolysmata (Crustacea: Caridea: Hippolytidae)
                           J. Antonio Baeza
                             Smithsonian Marine Station at Fort Pierce, USA

                  Shrimps from the ecologically diverse genera Lysmata and Exhippolysmata are rare among marine
                  invertebrates because they are protandric simultaneous hermaphrodites: shrimps initially reproduce
                  solely as males and later in life become functional simultaneous hermaphrodites. Considerable
                  progress on the reproductive ecology of the members from these two genera has been achieved during
                  the last decade. However, several outstanding issues of systematic nature remain to be addressed. Here,
                  a molecular phylogeny of these two genera was used to examine the overall evolutionary relationship
                  within and between species and genera and to answer various questions related to the systematic
                  status of several species. The present phylogenetic analysis, including 53 sequences and 26 species
                  of Lysmata and Exhippolysmata, indicates that semi-terrestrial shrimps from the genus Merguia
                  represent the sister group to a second natural clade composed by shrimps from the genera Lysmata and
                  Exhippolysmata. Also, the phylogenetic analysis demonstrated that the genus Lysmata is paraphyletic
                  and includes the genus Exhippolysmata. The tree partially supports the separation of species with
                  or without a developed accessory branch into two different genera or subgenera (Lysmata and
                  Hippolysmata having or not a well developed accessory branch, respectively). Genetic distances of the
                  cleaner shrimps L. amboinensis and L. grabhami were smaller than those observed between other sister
                  species. On the other hand, the topology of the tree indicates that these two entities are reciprocally
                  monophyletic. Thus, this latter result together with minor but constant differences in the color pattern
                  reported for these two entities indicates that there is no reason to stop treating them as different valid
                  species. This study allowed resolving standing taxonomic questions long overdue in shrimps from the
                  genera Lysmata and Exhippolysmata. In the future, this phylogeny will help revealing the conditions
                  favouring the origins of several behavioural and morphological novelties in these unique shrimps.



                                                                          57




General (poster).indd 57                                                                                                                09.8.11 9:10:36 AM
                    General Contributed Papers (posters)

                    [GP-9] Molecular phylogeny of the European shrimp genera Palaemon and Palaemon-
                           etes (Crustacea, Decapoda, Palaemonidae)
                            Jose A. Cuesta 1) , Christoph D. Schubart 2) , Antonio Rodriguez 1) , Pilar Drake 1) , Gonzalo
                            Martinez-Rodriguez1)
                               1)
                                    Instituto de Ciencias Marinas de Andalucía, Spain; 2) Biologie 1, Universität Regensburg, Germany.

                    The genera Palaemon Weber and Palaemonetes Heller are well represented in European marine, estua-
                    rine, and freshwater systems. Varying degrees of tolerance to waters of different salinities allow coex-
                    istence of a high number of these species within a short range of distribution. In European waters, there
                    are six species of Palaemon (P. elegans, P. serratus, P. xiphias, P. adspersus, P. longirostris, and the re-
                    cently introduced P. macrodactylus) and four of Palaemonetes (P. varians, P. zariquieyi, P. antennarius
                    and P. turcorum). The morphological differences that support the present separation in Palaemon and
                    Palaemonetes are minor. Only the presence or absence of a mandibular palp and the denticulation of
                    the rostrum seem to be useful characters; other features do not always allow clear distinction between
                    these genera. We obtained 16S mtDNA sequences for all of these ten European species and analysed
                    them together with sequences of Palaemonetes pugio, Palaemonetes argentinus, P. texanus and P. vul-
                    garis from America, Palaemon serrifer and Palaemonetes sinensis from Asia, and Palaemon serenus,
                    Palaemonetes australis, and Palaemonetes atrinubes from Australia. Our results confirm the validity
                    of the published hypothesis, based on the Australian species, claiming paraphyly of these two genera.
                    The different monophyletic clades obtained in our analysis perfectly reflect the geographic distribution
                    of these species. Among the European species, the genus Palaemonetes is well supported as mono-
                    phyletic taxon, including the type species (P. varians), whereas the genus Palaemon, including the type
                    species P. adspersus, only appears as monophyletic clade without P. elegans.




                    [GP-10] Latreutes koreanus sp. nov. from Korea confused with a scyphozoan associate
                           Latreutes anoplonyx Kemp (Decapoda: Caridea: Hippolytidae)
                            Hoi Jeong Yang1), Ken-Ichi Hayashi2)
                               1)                                                                         2)
                                 Basic Science Team, Gwacheon National Science Museum, Korea;                  Laboratory of Shrimp and Prawn,
                               Shimonoseki, Japan

                    Latreutes koreanus sp. nov. is described and illustrated based on specimens collected from Namhae,
                    southern Korea. The first zoea obtained from scyphozoan associate Latreutes anoplonyx Kemp, 1914 is
                    also described. Latreutes anoplonyx has been known to be free-living in sea grasses or associated with
                    scyphozoan medusa. We examined the first zoea obtained from scyphozoan associate L. anoplonyx
                    with Nemopilema nomurai, and found that the zoea is significantly different from that released from
                    free-living L. anoplonyx: the presence of a pair of dorsolateral spines on the fifth abdominal somite
                    only. Careful examination of the adult specimens including ovigerous females also disclosed that
                    two different species have been placed under the name of L. anoplonyx: the associated shrimp with
                    scyphozoan medusa is the true L. anoplonyx; free-living one collected from Namhae, southern Korea,
                    has not been treated as a distinct species so far. Therefore, herein, the latter is described as Latreutes
                    koreanus sp. nov.




                                                                                 58




General (poster).indd 58                                                                                                                         09.8.11 9:10:36 AM
                  General Contributed Papers (posters)

                  [GP-11] An unfamiliar species of the hydroid-associated pontoniine shrimp (Decapoda:
                         Caridea: Palaemonidae) from Suruga Bay, Japan
                           Junji Okuno
                             Coastal Branch of Natural History Museum and Institute, Chiba, Japan

                  In seven genera of the subfamily Pontoniinae, the presence of a median process on the fourth thoracic
                  sternite is considered one of their generic diagnoses. Pontoniine shrimps belonging to the genera
                  Cuapetes Clark, 1919, Eupontonia Bruce, 1971, Exoclimenella Duris and Bruce, 1994, Harpilius
                  Dana, 1852, Periclimenella Duris and Bruce, 1994, Philarius Holthuis, 1952, and Vir Holthuis, 1952
                  possess this structure. I was able to examine three specimens of an unfamiliar pontoniine shrimp
                  being associated with a sessiled hydroid, Litocarpia niger (Nutting, 1906) (Cnidaria: Hydrozoa:
                  Leptomedusae) from Suruga Bay, Pacific coast of central Honshu, Japan. In morphological and
                  ecological aspects, this species is assignable to the genus Rapipontonia Marin, 2007. This genus
                  consists of two hydroid-associated species from the Indo-West Pacific and a black coral associate from
                  the Eastern Atlantic, and is characterized on account of the ambulatory pereopods with the propodi
                  being strongly spinose distoventrally, and with the long and curved dactyli. But the fourth thoracic
                  sternite of the hydroid associate from Suruga Bay is armed medially with a finger-like process, instead
                  of the absence of the process in the Rapipontonia species. In contrast, all known species armed with a
                  median process on the thoracic sternite lack the characteristic spination on the ambulatory pereopods
                  mentioned above. Therefore, to accommodate its taxonomic position, I regarded that a new genus
                  should be proposed for the undescribed species from Suruga Bay.




                  [GP-12] A study of the stock enhancement of Greasyback Shrimp Metapenaeus ensis
                         based on reproductive examination in the Ise Bay, central Honshyu, Japan
                           Fumihiro Yamane1), Katsuyoshi Suitoh2), Keisuke Yamano3)
                             1)
                               Mie Prefectural Fish Farming Center, Japan; 2) Aichi Prefectural Sea Farming Institute, Japan;   3)
                                                                                                                                     National
                             Researach Institute of Aquaculture, Fisheries Research Agency, Minamiise, Japan

                  Greasyback Shrimp, Metapenaeus ensis is one of important species for coastal fisheries in Japan.
                  Here we report a study of the stock enhancement based on the annual reproductive cycle of female
                  shrimp at shallow estuarine water in the Ise Bay. The reproductive resting period was estimated to be
                  from November to May, because all females had immature ovaries with non-vitellogenic oocytes. The
                  yolk accumulation in oocytes started at mid-June when the coastal water temperature reached 18 ºC.
                  Afterward, vitellogenic ovaries with oocytes at the late globule stage were observed from early July
                  to mid-September with the highest frequency in August when the water temperature was the highest
                  in the year. Spent females were also observed in this period. This period was thus considered to be the
                  reproductive season of the greasyback shrimp in the Ise Bay. On the other hand, the larval rearing in
                  hatcheries at lower than 25 ºC decreased the larval survival rate of this species. In the Ise Bay, in fact,
                  in the year of lower water temperature after the spawning season, a catch of 0-year-old shrimp in and
                  after October showed a tendency to be smaller than that in a usual year. Therefore, it is considered that
                  the fishery resources of the greasyback shrimp may decrease in the following year. Maintenance under
                  artificial conditions during the stages feeble against nutritional depletion and environmental changes
                  and the subsequent release of the produced juveniles into sea are effective to reduce the influence of
                  environmental impacts to the natural resource of the greasy back shrimp.




                                                                          59




General (poster).indd 59                                                                                                                        09.8.11 9:10:36 AM
                    General Contributed Papers (posters)

                    [GP-13] Change of the species composition and reduction of the resource in small spe-
                           cies of penaeid shrimp in Tosa Bay, Pacific coast of southwestern Japan
                            Hideo Sakaji1), Jun Yamamoto2), Makoto Harada3), Koichiro Mizoguchi4)
                               1)
                                 National Research Institute of Fisheries Science, Fisheries Research Agency, Japan; 2) Kochi Prefectural
                               Fisheries Experimental Station, Japan; 3) Marine Resources Research Center, Aichi Fisheries Research Institute,
                               Japan, 4) Miyazaki Prefectural Fisheries Experimental Station, Japan

                    Introduction: Some species of small penaeid shrimps (Metapenaeopsis and Trachysalambria) are
                    important for the small-scale trawl fisheries in the Pacific coast of central and southwestern Japan.
                    Recently, the catches of these shrimps have seriously reduced in Tosa Bay (33°N, 133°E). In this study,
                    we indicate the changes of the density and the species composition of the penaeid shrimps in Tosa
                    Bay and compare them with other localities, for clarifying the factor of the reduction of the penaeid
                    shrimps in Tosa Bay. Materials and methods: Specimens were collected in the six depth classes
                    (10-20m, 20-30m, 30-40m, 40-50m, 50-60m and 60-70m) in the central part of Tosa Bay by using
                    small-scale trawlers in spring of 1994, 1995, 1996, 1997, 1998, 2000, 2008 and 2009. All specimens of
                    penaeid shrimps were counted and weighed after the species identification. The species compositions
                    of penaeid shrimps of the catches of small-scale trawlers were surveyed also in Atsumi-gaikai (34°N,
                    137°E) and Hyuga-nada (32°N, 132°E) in 2008 and 2009, for the comparison. Results: In Tosa Bay,
                    the densities of penaeid shrimps in 2008 and 2009 were lower than those before 2000, especially in
                    20-30m, 30-40m and 40-50m depth classes. The dominant species before 2000 were Metapenaeopsis
                    dalei and Trachysalambria albicoma in 20-30m, M. barbata, M. dalei and T. albicoma in 30-40m,
                    M. barbata and M. sinica in 40-50m. But, those in 2008 and 2009 were M. dura and T. albicoma in
                    20-30m, M. dalei and M. dura in 30-40m and M. sinica in 40-50m. The reduction of M. barbata was
                    the main reason for the reduction of the catch of the penaeid shrimps in Tosa Bay. M. barbata did
                    not appear and M. dalei and M. mogiensis were dominant in the catch in Atsumi-gaikai, although M.
                    barbata was still dominant in Hyuga-nada.



                    [GP-14] Prawn diversity of the subfamily Palaemoninae of India and a concept note on
                           their utilization
                            K. V. Jayachandran
                               College of Fisheries, Kerala Agricultural University, India

                    Prawns of the subfamily Palaemoninae are highly important both commercial as well as ecological
                    point of view. Serious studies have been carried out on the biodiversity and taxonomy of Indian
                    freshwater prawns. A total of 76 species have been recorded under 8 genera: Exopalaemon Holthuis,
                    1950 (1 sp.); Leandrites Holthuis, 1950 (1 sp.); Leptocarpus Holthuis, 1950 (3 spp.); Macrobrachium
                    Bate, 1868 (60 spp.); Nematopalaemon Holthuis, 1950 (2 spp.); Palaemon Weber, 1795 (7 spp.);
                    Troglindicus Sankolli & Shenoy, 1979 (1 sp.); Urocaridella Borradaile, 1915 (1 sp.). A complete list of
                    the species is given in the text. Studies indicated that the distribution patterns of species are based on
                    habitat and altitude. Certain species are fully adapted to hill stream at high altitudes whereas some are
                    exclusively estuarine. Accordingly six grouping have been made. The present paper also attempts to
                    bring forth a concept note on the utilization of this precious diversity for culture operations, for capture
                    purposes, for candidate species for ornamental purpose, as forage organisms and also for utilizing as
                    value added products.




                                                                               60




General (poster).indd 60                                                                                                                         09.8.11 9:10:37 AM
                  General Contributed Papers (posters)

                  [GP-15] Population biology of the deep-water mud shrimp Solenocera melantho (Sole-
                         noceridae) in Kagoshima Bay, southern Japan
                           Daiki Tamari,1) Yoshiki Yamashita,1) Aki Atuchi,1) Kana Asakuma,1) Chihiro Tuzura,1) Miku
                           Hirayama,1 ) Ayano Yamashita,1) Ryouma Nishimoto,1) Hitoshi Sanuki ,1) Jun Ohtomi 2)
                             1)
                                  Kinkowan High School, Kagoshima; 2) Faculty of Fisheries, Kagoshima University, Japan

                  The deep-water mud shrimp Solenocera melantho (Decapoda, Solenoceridae) is commercially
                  important as the main target species for small-scale bottom seiners in Kagoshima Bay, southern Japan.
                  Since the 1990s some studies have been conducted on the biological characteristics of S. melantho
                  population in the bay (e.g., Ohtomi and Irieda, 1997, Ohtomi et al., 1998). Further, statistics indicate
                  declining catches over recent years, calling for assessment of the present status of the population of this
                  species in the bay. The objective of the present study was therefore to investigate the spawning season
                  and growth of S. melantho in Kagoshima Bay using specimens collected during January through
                  December 2008. Sampling was conducted monthly in the bay during daytime onboard Nansei-Maru
                  (175t), a training vessel of the Faculty of Fisheries, Kagoshima University and chilled in ice before
                  transfer to the laboratory for analyses. Estimation of the spawning season was based on gonadosomatic
                  index and developmental stage of oocytes from each individual and the growth pattern and longevity
                  estimated using monthly length-frequency distribution. In total, 2,273 specimens were collected during
                  the present sampling period. The size at sexual maturity for females was estimated at 22 mm carapace
                  length (CL). The spawning season lasted from August through November, with a peak during October
                  and November. Both males and females were first recruited in December with modal sizes averaging
                  at 10 mm CL. The growth of S. melantho was described by the von Bertalanffy equation with females
                  recording larger body sizes than males of the same age group. The longevity of this species was
                  estimated to be a little more than two years for both sexes. Comparatively, the spawning period and
                  longevity of the present population were slightly shorter than those of the population in the 1990s
                  (Ohtomi and Irieda, 1997; Ohtomi et al., 1998).



                  [GP-16] Current status of the pandalid shrimp Plesionika semilaevis population in Ka-
                         goshima Bay, southern Japan
                           Jun Ohtomi, Kenji Kumagai
                             Faculty of Fisheries, Kagoshima University, Japan

                  Kagoshima Bay, southern Japan, is a semi-enclosed bay with water depths reaching more than
                  230 m and unique environmental features. Monitoring of species composition of mega-benthos
                  including pisces, crustaceans (Decapoda, Stomatopoda, Mysidacea and Euphausiacea) and molluscs
                  (Cephalopoda, Bivalvia and Gastropoda) in this bay was conducted using experimental bottom trawl
                  surveys onboard the Nansei Maru (175 t), a training vessel of the Faculty of Fisheries, Kagoshima Uni-
                  versity, Japan. Until 1990s, the deep-water pandalid shrimp Plesionika semilaevis (Decapoda, Caridea)
                  was a principle by-catch of small-scale bottom seine fishery in Kagoshima Bay, and the market price
                  of this species was low. However, utilization of P. semilaevis as a local resource has significantly
                  increased over recent years, with high potential as sashimi and other processed food products. In the
                  current study, the biological aspects of P. semilaevis population in Kagoshima Bay, including the size
                  at sexual maturity, reproductive season, brood size and growth pattern, were examined using specimens
                  collected during April 2008 through March 2009. The size at sexual maturity was estimated at 11.4
                  mm carapace length. Ovigerous females occurred from May to December, and the hatching period was
                  estimated to last from June through December, based on the occurrence of ovigerous females with late-
                  stage embryos. The brood size of P. semilaevis ranged from 1,051 to 7,982 for non-eyed stages and
                  from 1,046 to 5,854 for eyed stages. There was a positive correlation between the body size and the
                  brood size for both the non-eyed and eyed stages. Growth patterns for both sexes were best modeled
                  by fitting the von Bertalanffy growth equation to the mean carapace lengths at ages, indicating no
                  seasonal oscillation in growth rate. The results of the current study are further discussed in comparison
                  to the earlier study using specimens collected in 1990s in Kagoshima Bay (Ohtomi, 1997).



                                                                             61




General (poster).indd 61                                                                                                        09.8.11 9:10:37 AM
                    General Contributed Papers (posters)

                    [GP-17] Classification and morphological investigation of Macrura species imported
                           from twenty-one countries by Japan
                            Makoto Murofushi1), Yuji Hasegawa2), Makoto Hirose1), Ryutaro Ueda1)
                               1)
                                    Department of Food and Nutrition, Nihon University, Japan; 2) Hakone-en Aquarium, Kanagawa, Japan

                    Japan is consuming about 250,000 tons of edible Macrura in a recent year. Ninety percent of them
                    were imported from foreign countries. Only ten percent were supplied by domestic products of Japan.
                    Present study identified edible Macrura species from foreign countries after 1996 by the morphological
                    investigation. Materials used for the identification of Macrura species were obtained from the
                    institutions of sea foods at Tokyo and Osaka. Specimens of whole body were used for the identification
                    of species. Headless and/or peeled specimens could not be identified the species by the morphological
                    characteristics. Total 567 specimens from twenty-one countries among 14 years were investigated
                    for the identification of the species. Thirty species belonging to 9 families (Penaeidae, Solenoceridae,
                    Sergestidae, Palaemonidae, Pandalidae, Nephropidae, Nephropoidae, Palinuridae and Scyllaridae)
                    of Macrura, Decapoda were identified from imported specimens. These were including 18 Genuses.
                    Two species of them were imported from plural countries. One is Penaeus semisulcatus from
                    Indonesia, Papua New Guinea, Australia and Bahrain, and another one is Pandalus eous from Russia,
                    Greenland (Denmark territory) and Canada. Total species numbers from twenty-one countries were
                    counted 35. These were obtained 3 species from North America, 3 species from Middle and South
                    America, 7 species from Oceania, 1 species from Middle East, 6 species from Africa and 1 species
                    from Europe respectively. The most species number of 6 was imported from Indonesia. These thirty
                    species were discriminated in 14 species in lobsters, 15 species in prawns and 1 species in shrimp.
                    Numerous species were found in 9 species of Palinuridae and 8 species of Penaeidae. Fifteen species
                    have no distribution from the coast of Japan. The morphological characteristics of all specimens were
                    investigated minutely.




                    [GP-18] Digestive enzyme activity of Nephrops norvegicus fed different diets
                            Guiomar Rotllant1), Enric Gisbert1), Ioannis T. Karapanagiotidis2), Elena Mente2)
                               1)
                                IRTA, Unitat de Cultius Experimentals. Carretera del Poblenou, Spain; 2) School of Agricultural Sciences,
                               Department of Ichthyology and Aquatic Environment, University of Thessaly, Greece.

                    The digestive physiology of Nephrops norvegicus was investigated in adults (initial mean weight: 26.2
                    g) fed with different diets (fresh mussel, compound diet for prawns and food deprivation). Fifteen
                    animals were reared individually during 6 months (5 animals per dietary regime; each animal is
                    considered to be a replicate). The following digestive (pancreatic, gastric and intestinal) enzymes were
                    quantified by spectophotometry: total proteases, trypsin, chimotrypsin, pepsin, aminopeptidase-N,
                    amylase and alkaline phosphatase. Norway lobster fed with fresh food increased their body weight
                    in a 30.8% whereas those fed with inert diets only grew a 14.5%. Specimens without food supply did
                    not show any change in body weight and the lowest digestive enzyme activities. Trypsin activity in
                    lobster fed with the inert diet doubled that of those animals fed with fresh mussel (p<0.05), whereas
                    no significantly differences between these groups were detected in total protease and chymotrypsin
                    activities (p>0.05). Pepsin activity in the inert diet-fed group was higher than that of animals fed
                    the fresh diet. Significantly higher levels of amylase were detected in Norway lobster fed with inert
                    diet while fresh mussel fed animals showed intermediate values between the formed and the food
                    deprived group (p<0.05). The amylase/trypsin ratio was not affected by the dietary treatment (type of
                    food and fasting). Knowledge on crustacean nutrition progresses slower than that of fish because of
                    the experimental difficulties caused by moulting and by the feeding habits of crustaceans. Different
                    digestive enzyme patterns between diets were mainly due to their different nutrient composition. These
                    results indicated that Norway lobster is able to digest and assimilate inert diets formulated for other
                    crustacean species, although different patterns in growth and digestive enzyme activities show that
                    further improvements in diets formulation for this species is needed since animals fed with fresh food
                    showed a superior performance.


                                                                               62




General (poster).indd 62                                                                                                                    09.8.11 9:10:37 AM
                  General Contributed Papers (posters)

                  [GP-19] Egg biochemical composition of the norway lobster Nephrops norvegicus during
                         the embryonic development: field and laboratory change patterns
                           I. Álvarez-Fernández1), G. Rotllant3), F. Sardà2), A. Malzand4), P. Verisimo1), L. Fernández1)
                             1)
                                Departamento de Bioloxía Animal, Bioloxía Vexetal e Ecoloxía, Universidade da Coruña, Spain; 2)Departement
                             de Recursos Marins Renovables, Institut de Ciències del Mar, CSIC, Spain; 3)Centre d'Aqüicultura, IRTA, Spain;
                             4)
                                Alfred Wegener Institute for Polar and Marine Research, Biologische Anstalt Helgoland, Germany.

                  Nephrops norvegicus is a species of great commercial interest in Spain, with a critical fishery situation.
                  A study on the reproductive biology of this species was carried out among 2005-2007 in Galician (NW
                  Spain) and Mediterranean Coast. This work compares biochemical changes during the embryonic
                  development of N. norvegicus (L) collected from their natural habitat and reared in laboratory. Previous
                  to spawn period (July-August) non-ovigerous females from the North Western Mediterranean Sea and
                  North Eastern Atlantic Sea were caught in order to be reared in laboratory along the egg development.
                  Reared females lasted around 40 to 60 days to spawn from the catch date, and during the whole period
                  they were fed with frozen mussels. After the spawn, eggs samples were taken monthly along the
                  embryonic development. On the other hand, ovigerous females from both areas were caught monthly
                  from September 2003 to February 2004, during eggs incubation period. Biochemical analyses of
                  spawns were performed to determine organic (lipids, proteins, carbohydrates and DNA) and inorganic
                  matter (ash) content. Results showed that egg lipid content suffered the bigger differences, with a
                  greater content in Atlantic spawns than in the Mediterranean ones, and bigger changes in laboratory
                  spawns than in the field ones along the embryonic development. Protein content of the reared females
                  showed a different variation pattern from wild females along the embryonic development. The rest of
                  the parameters studied showed similar patterns in all the cases studied.




                  [GP-20] Interpopulational comparison of fecundity of the gonochoric shrimp Hippolyte
                         obliquimanus Dana, 1852 (Caridea: Hippolytidae)
                           Mariana Terossi1,2), Ingo Wehrtmann3), Fernando L. Mantelatto1)
                             1)
                              Laboratory of Bioecology and Crustacean Systematics, Faculty of Philosophy, Sciences and Letters of Ribeirão
                             Preto (FFCLRP), University of São Paulo (USP), Brazil; 2) Program of Post Graduation on Comparative
                             Biology – FFCLRP (USP); 3) Centro de Investigación en Ciencias del Mar y Limnología (CIMAR), and Escuela
                             de Biología, Universidad de Costa Rica, Costa Rica. Financial support: FAPESP (DR 06/61771-0), CNPq (Proc.
                             490353/2007-0), CONICIT (CII-001-08) and UCR (VI 808-A8-209)

                  Hippolyte obliquimanus is a shrimp endemic to the Western Atlantic coast, and its distribution is
                  restricted to shallow waters of the Caribbean and off Brazil, always associated with seagrass. The aim
                  of the present study was to compare the fecundity and the egg volume between two populations (Brazil
                  – Costa Rica) of H. obliquimanus, in order to improve our knowledge concerning the reproduction
                  of this poorly studied species. The ovigerous females were collected by hand in the Itaguá Beach
                  (Ubatuba/SP, Brazil, 23º27’414”S – 45º03’047”W) and in Cahuita Beach (Limón, Costa Rica, 09º
                  39’304”N – 82º45’163”W). For this study, we analyzed only females with recently-produced eggs
                  (uniform yolk and without visible eye pigment). All eggs were counted and fifteen eggs of each female
                  were separated, and smallest and largest diameters were measured to calculate the egg volume. In
                  total, 83 ovigerous females were analyzed (38 from Brazil and 45 from Costa Rica). We encountered
                  differences between the localities: egg volume was significantly larger in Brazil (0.016 ± 0.004 mm3)
                  than in Costa Rica (0.012 ± 0.003 mm3), and the fecundity was significantly higher in Costa Rica (190
                  ± 103 eggs) than in Brazil (131 ± 94 eggs), with no significant differences in shrimp size between
                  the two populations. The production of larger eggs may be interpreted as an adaptation to lower
                  water temperatures (Brazil). Females of the same size producing larger eggs (Brazil) have less space
                  available in the abdomen for egg attachment, which may explain the lower fecundity when compared
                  with females carrying small eggs (Costa Rica). The results of our interpopulational study provide
                  evidence for the considerable plasticity in the reproductive biology of this hippolytid shrimp.




                                                                           63




General (poster).indd 63                                                                                                                      09.8.11 9:10:38 AM
                    General Contributed Papers (posters)

                    [GP-21] Distribution and ecology of the deep-water shrimp Acanthephyra brevicarinata
                           Hanamura, 1984 (Caridea: Oplophoridae) off the Pacific coast of Mexico
                            Michel E Hendrickx
                              Universidad Nacional Autonoma de Mexico, Mexico

                    A total of 137 specimens of the deep-water caridean shrimp Acanthephyra brevicarinata Hanamura,
                    1984, were collected of the Pacific coast of Mexico in deep-water trawls, between 2005 and 2007.
                    These records complete the samples that were previously reported from the SE Gulf of California by
                    Hendrickx (2003). The new series or material was trawled with a bottom sledge in the SE and Central
                    Gulf of California and off the coast of SW Mexico (roughly between Banderas Bay and Acapulco).
                    The depth range at which the sledge was operated was 820 to 2394 m. Acanthephyra brevicarinata has
                    been reported as a pelagic species, but abundance of the material in some samples combined by the
                    small size of the sampling gear (ca 2.5 m wide) indicate that, at least in the case of medium to large-
                    size specimens, this species would rather be benthic. Previous to this study there has be no record of
                    A. brevicarinata south of the Gulf of California. The species geographic range is increased by about
                    five degrees of latitude to the south and about two degrees to the north. Environmental data associated
                    with the sampling at bottom level were: depth, 1037 to 2394 m; dissolved oxygen, 0.24 to 2.37 ml
                    O2/l; water temperature, 2.02 to 4.42 oC. As in the case of some other deep-water decapods collected
                    in the same area, A. brevicarinata features a good tolerance to low oxygen concentration, with 24% of
                    records in environment with <0.5 ml O2/l and 64% of records in environment with <1.0 ml O2/l. The
                    species was not found in depth shallower than 1000 m. However, relationship between catch-size and
                    depth shows a strong tendency to patchiness in its distribution.




                    [GP-22] Breeding cycle of the slipper lobster Scyllarus arctus in the Galician Coast (NW
                           Spain)
                            L. Fernández1), C. García2), I. Alborés1)
                              1)
                               Departamento de Bioloxia Animal, Bioloxia Vexetal e Ecoloxia, Fac. de Ciencias, Universidad de A Coruña,
                              Spain; 2) Aquarium Finisterrae, A Coruña, Spain

                    The slipper lobster Scyllarus arctus is a species of great commercial interest on the coast of Galicia
                    (NW Spain). A study is being carried out on the biology of this species to improve the management of
                    its fishery. The present work deals with the breeding cycle of S. arctus, based on field and laboratory
                    studies. The breeding cycle of the slipper lobster was studied based on monthly samples (from January
                    2008 to January 2009) collected in the Galician coast, and laboratory experiments holding ovigerous
                    females in captivity. During the sampling period 1741 individual were caught, 761 males and 981
                    females (43,69% and 56,31%, respectively). A total of 508 ovigerous females (29,16% of the total
                    females) were analyzed in order to define the seasonal breeding pattern. Results showed that, despite
                    ovigerous females were found along the whole annual period studied (except in October), there are one
                    main breeding period from February to August. During this period the percentage of ovigerous females
                    was always higher than 50%, and more than 70% from February to May, and July. The analysis of
                    the early spawn sizes, corrected by the size of the female, showed statistically significant differences
                    among months, being spring spawns bigger than the rest. On the other hand, in the study carried out
                    at the laboratory 7 ovigerous females were monitored from February 2007 to June 2007. The egg
                    development lasted from 44 to 55 days, depending on the water temperature. One female spawned
                    twice during the laboratory monitoring, lasting 3-4 days between consecutive spawns.




                                                                          64




General (poster).indd 64                                                                                                                  09.8.11 9:10:38 AM
                  General Contributed Papers (posters)

                  [GP-23] Seasonal change in the ovary of the Japanese crayfish, Cambaroides japonicus
                           Mitsutaka Hasegawa1), Hajime Matsubara1), Yoshifumi Horie1), Ayaka Chiba1), Daisuke Iwata1),
                           Takahiro Kinoshita1), Kazuyoshi Nakata2)
                             1)                                                                                         2)
                              Department of Aquatic Biology, Tokyo University of Agriculture, Abashiri, Japan;               Public Works
                             Research Institute, Tsukuba, Japan

                  The Japanese crayfish, Cambaroides japonicus, only lives in cold brooks and lakes in northern Japan.
                  The number of Japanese crayfish drastically declined, as the result the Japanese Fisheries Agency in
                  1998 and the Environment Agency in 2000 declared it as an endangered species. However, there is a
                  little information to produce its seed. To establish the suitable seed production of Japanese crayfish,
                  it is necessary to understand the detailed knowledge of its gametogenesis. In this study, we focused
                  on the seasonal change in the ovary of Japanese crayfish. Just after spawn, the Japanese crayfish
                  mainly had primary growth phase oocytes in spring. The stage of oocytes in summer was showed
                  the vittellognic stage. However, some of late vitellogenic stage oocytes were also observed in spring
                  and summer. In autumn, the Japanese crayfish after mating had late vitellogenic stage oocytes. In
                  addition, the stage of oocytes in severe winter was showed the maturation phase. From this result,
                  we hypothesized that the Japanese crayfish under control of rearing condition has the potentiality of
                  earlier spawning. Furthermore, this findings might be useful for the establishment multiple spawning
                  technique of the Japanese crayfish in the future.




                  [GP-24] Seasonal change in the testis and vas deferens of the Japanese crayfish, Camba-
                         roides japonicus
                           Ayaka Chiba1), Hajime Matsubara1), Yoshifumi Horie1), Daisuke Iwata1), Mitsutaka Hasegawa1),
                           Kinoshita Takahiro1), Kazuyoshi Nakata2)
                             1)                                                                              2)
                               Dept. of Aquatic Biology, Tokyo University of Agriculture, Abashiri, Japan;        Public Works Research
                             Institute, Tsukuba, Japan

                  In General, the reproductive cycle of the Japanese crayfish (Cambaroides japonicus) can be described
                  as: mating between September and October, female spawn in May of the following year and eggs hatch
                  in July (Kawai and Saito, 2001). However, we observed the wild males did mating just before spawn.
                  What was the true motive behind this behavior? In the present study, we therefore studied the seasonal
                  change in the male reproductive system of the Japanese crayfish. After spawning season, the testis and
                  vas deferens of Japanese crayfish mainly had immature male germ cells. In contrast, the testis and vas
                  deferens from summer to spawning season was observed the sperm. These finding strongly suggested
                  that the male Japanese crayfish might do multiple mating from summer to next spring.




                                                                        65




General (poster).indd 65                                                                                                                    09.8.11 9:10:38 AM
                    General Contributed Papers (posters)

                    [GP-25] Seasonal change in the testis and vas deferens of the American signal crayfish,
                           Pacifastacus trowbridgii
                            Yoshifumi Horie1), Hajime Matsubara1), Daisuke Iwata1), Yuta Fukuoka1), Takamasa Suzuki1),
                            Ayaka Chiba1), Mitsutaka Hasegawa1), Takahiro Kinoshita1), Kazuyoshi Nakata2)
                               1)                                                                              2)
                                Dept. of Aquatic Biology, Tokyo University of Agriculture, Abashiri, Japan;         Public Works Research
                               Institute, Tsukuba, Japan

                    The American signal crayfish, Pacifastacus leniusculus (Dana, 1852) was first introduced into Lake
                    Mashu, eastern Hokkaido, Japan from North America for use as food in 1928. However, they recently
                    had a widespread distribution in Hokkaido. On 2006, they were designated ‘invasive alien species’
                    by the Ministry of the Environment of Japan. To exterminate the American signal crayfish from
                    unexpected area in Japan, it is necessary to grasp the detailed reproductive system of American signal
                    crayfish. Here we reported the seasonal change in the testis and vas deferens of the American signal
                    crayfish, in lake Shikaribetsu, Hokkaido, Japan. The size of first and second pleopods are increased
                    depend of those of their carapace and body size. These results showed that the larger size crayfish was
                    profitable for mating as a matter of course. However, the sperm were not simply observed in the testis
                    and vas deferens of larger crayfish, but also smaller crayfish. These findings suggested that the smaller
                    size crayfish also has a potential for mating. It is therefore necessary to collect all size of crayfish, in
                    order to exterminate.




                    [GP-26] Seasonal change in the ovary of the American signal crayfish, Pacifastacus
                           trowbridgii
                            Daisuke Iwata1), Hajime Matsubara1), Takamasa Suzuki1), Yuta Fukuoka1), Yoshifumi Horie1),
                            Ayaka Chiba1), Mitsutaka Hasegawa1), Takahiro Kinoshita1), Kazuyoshi Nakata2)
                               1)                                                                              2)
                                 Dept. of Aquatic Biology, Tokyo University of Agriculture, Abashiri, Japan;        Public Works Research
                               Institute, Tsukuba, Japan

                    In Japan, the only native crayfish species, Cambaroides japonicus (De Haan, 1841), lives in cold
                    brooks and lakes in northern Japan. However, the American signal crayfish, Pacifastacus leniusculus
                    (Dana, 1852) recently had a widespread distribution in Hokkaido. As the result, the American signal
                    crayfish together with another American crayfish (Orconectes rusticus), Cherax spp. and Astacus
                    spp. were designated ‘invasive alien species’ by the Ministry of the Environment of Japan. Recently,
                    the Japanese crayfish populations have markedly declined. Important reasons for this decline are
                    considered to be from river improvements and from impacts of the invasive crayfish species the
                    American signal crayfish (Kawai et al., 2002). To preserve the native Japanese crayfish populations, it
                    is indispensable to exterminate the American signal crayfish. However, there is a little information of
                    the reproductive system of American signal crayfish. In this study, we report the seasonal change in the
                    ovary of the American signal crayfish in lake Shikaribetsu, Hokkaido, Japan.




                                                                          66




General (poster).indd 66                                                                                                                    09.8.11 9:10:38 AM
                  General Contributed Papers (posters)

                  [GP-27] Effect of pH and water temperature on the development of the Japanese cray-
                         fish, Cambaroides japonicus, egg in vitro
                           Natsuko Yasumoto1), Ayaka Chiba1), Yoshifumi Horie1), Takahiro Kinoshita1), Marie Ichikawa1),
                           Daisuke Iwata1), Takamasa Suzuki1), Yuta Fukuoka1), Kazuyoshi Nakata2), Hajime Matsubara1)
                             1)                                                                              2)
                               Dept. of Aquatic Biology, Tokyo University of Agriculture, Abashiri, Japan;        Public Works Research
                             Institute, Tsukuba, Japan

                  The Japanese crayfish, Cambaroides japonicus, is the only native crayfish species in Japan. They
                  spawn in May, and carries eggs and hatchlings for two to three months. Therefore, the survival ratio of
                  eggs and hatchling flies depends on their mother. However, the potential negative effects of the mother,
                  for example, egg loss, death of the mother and a decline in water quality were sometimes caused
                  in wild. To prevent these effects, the artificially cultivating eggs separate from mother was suitable
                  methods. So far, Nakata et al. (2004) developed a simple, easy method with a microplate to artificially
                  incubate eggs for their cultivation. In the present study, we examined the suitable conditions (pH and
                  water temperature) for artificially cultivating Japanese crayfish eggs.




                  [GP-28] How the previous ownership of a resource influences the agonistic behavior of
                         crayfish
                           Elena Tricarico, Francesca Gherardi
                             Department of Evolutionary Biology, University of Florence, Italy

                  There is plenty of evidence that resource value is one of the most important non-strategic variables
                  in animal fighting behavior, thus influencing fight outcomes. However, the advantage provided to a
                  contestant by its prior ownership has been largely neglected. Here, we tested whether the possession
                  of a shelter might modify the agonistic behavior of the crayfish Austropotamobius pallipes, eventually
                  increasing its probability to win, when it reencounters a previously met conspecific away from this
                  resource. The agonistic behavior of familiar pairs composed of similarly-sized males was observed for
                  an hour after that the two contestants had been kept in isolation for two days, either in the presence or
                  in the absence of a shelter. Specifically, in the isolation phase a shelter was offered to (1) both crayfish,
                  (2) no crayfish, (3) the dominant crayfish only, and (4) the subordinate crayfish only. The following
                  combat was conducted in the absence of any refuge. Independently of its rank, the crayfish that
                  previously owned a shelter showed a higher aggressive motivation to fight than the individuals kept
                  without a shelter. Subordinate crayfish were even more aggressive than dominants but were never able
                  to revert hierarchies. Taken together, our results confirm the role played by shelters as determinants of
                  agonism but also show for the first time how the behavior of crayfish and their internal state may be
                  affected by their prior ownership of a resource.




                                                                            67




General (poster).indd 67                                                                                                                  09.8.11 9:10:39 AM
                    General Contributed Papers (posters)

                    [GP-29] Reproduction and inheritance of the color variants of the crayfish, Procambarus
                           clarkii
                            Ferdoushi Begum1), Satoshi Tamotsu1), Taichiro Goto2)
                               1)                                                                      2)
                                 Biological Science and Environment, Nara Women’s University, Japan;        Science Education, Mie University,
                               Japan

                    The body color of crayfish Procambarus clarkii is variable and colorful morphs are known, such as
                    blue, orange, red and albino. Albino has been already established as a strain, but it is not widely used
                    in biological research and education. On blue color variants, there was no established strain, although
                    there were few studies on the inheritance of blue morph. Most of the crayfish studies have been done
                    using wild type. In order to promote the usage of color variants like wild type, we tried to obtain some
                    basic knowledge on the color variants. In the present study, we examined the reproductive ability of
                    albino and inheritance pattern of blue morph. The reproductive ability of albino morph was compared
                    with wild type and the effect of single and multiple mating on the reproductive ability was examined.
                    The results showed that the reproductive ability of albino morph was lower than wild type and two
                    males took part in fertilization when females mated with two males successively. The inheritance
                    of a blue morph was examined by the cross experiments with albino morph and blue morph in four
                    generation. The body color of all F1 was normal color as seen in wild type. It was hypothesized that
                    two genes would be related to the body coloration of blue morph, albino morph and wild type. The
                    cross experiments of F1 and later generations, including backcrossing, produced offspring with color
                    phenotypes of wild type, blue morph and albino morph with expected ratios. Our study elucidated
                    the inheritance of these three body color phenotypes in P. clarkii, although further study is needed to
                    establish the strain of the blue color variant.




                    [GP-30] The use of the European eel (Anguilla anguilla) in the management of invasive
                           crayfish populations
                            Laura Aquiloni, Sara Brusconi, Elena Cecchinelli, Elena Tricarico, Giuseppe Mazza, Annalisa
                            Paglianti, Francesca Gherardi
                               Department of Evolutionary Biology, University of Florence, Italy

                    The red swamp crayfish, Procambarus clarkii, is a paradigmatic invader of freshwater ecosytems in
                    Europe. Several attempts have been made to mitigate the multilevel impact of this species but none
                    has been successful. Among the different methods proposed, the use of the European eel (Anguilla
                    anguilla) as an indigenous predator is promising. In fact, this species shows nocturnal feeding habits
                    and benthonic behaviour, which both match the crayfish’s life-style. However, scientific information
                    about this species’ predatory ability on crayfish is still scanty. Here, we analyzed whether the
                    introduction or the restoration of eel populations might help in the management of P. clarkii in Italy.
                    Three experiments were run, in the laboratory, in enclosures, and in the field, respectively. Overall
                    our results showed that eels have a specific technique to prey on P. clarkii, mostly preying on small-
                    sized and/or soft-shelled individuals. They also decrease the crayfish trophic activity, possibly leading
                    to an increased crayfish mortality. Finally, their use, if combined with trapping, might affect the whole
                    population of crayfish. However, the experiments also revealed some negative aspects, such as the
                    eels’ low predation rate, that should be appropriately assessed before any intervention.




                                                                              68




General (poster).indd 68                                                                                                                         09.8.11 9:10:39 AM
                  General Contributed Papers (posters)

                  [GP-31] Genotyping of Hanasaki crab using DNA extracted from shell tissues: a kind
                         methodology to the large crustaceans
                           Minoru Ikeda1), Ryoji Kudo2), Nobuhiko Taniguchi3)
                             1)
                               Graduate School of Agricultural Science, Tohoku University, Japan; 2) Nemuro Fisheries Research Institute,
                             Japan; 3) Department of Marine Biotechnology, Fukuyama University, Japan

                  In the genotyping for population genetic study of large crustaceans in the wild or aquaculture system,
                  muscle of the leg (pereiopod or pleopod) amputated from living individual has been frequently used
                  for DNA extraction. We always expect that the individuals released would survive and the lost leg
                  completely regenerates after several molting. But the individuals would be subjected to greater stress
                  and risk of attack by predators or pathogens. Additionally, if the species is commercially important,
                  the price of legless individual is lower than normal one. Recently, Kudo (2007) suggested novel and
                  valid tagging system in Hanasaki crab (= spiny king crab) by clipping edge of the carapace. If a piece
                  of carapace clipped is available for genotyping, we can develop a kind genotyping methodology to the
                  crab. Thus we examined whether we can do genotyping using DNA extracted from the shell tissues.
                  At first, we observed shell and inner membrane of the carapace under a fluorescent microscopic with
                  DAPI staining, and found out the presence of DNA molecules in both tissues. Total DNA was extracted
                  from the shell, inner membrane and soft rim of the carapace of each of six crabs using a routine
                  procedure (TNES-Urea/phenol/chloroform method), and five microsatellite and mitochondrial DNA
                  (a part of AT-rich region sequences) genotypes were determined. All of genotypes were successfully
                  determined when the DNA from inner membrane and soft rim were used, and the genotypes were
                  completely identical to those amplified using the DNA extracted from muscle. These results indicate
                  that genotyping using shell tissues of carapace (especially, inner membrane and soft rim) is entirely
                  possible in Hanasaki crab, and suggest availability to the endangered or expensive large crustaceans.




                  [GP-32] Sexual dimorphisms of fossil Callianassoidea (Decapoda: Thalassinidea): ex-
                         amples in Japanese Cenozoic species
                           Hisayoshi Kato1), Hiroaki Karasawa2)
                             1)
                                  Natural History Museum and Institute, Chiba, Japan; 2) Mizunami Fossil Museum, Japan

                  Due to the selective preservation of strongly calcified chela in compare with other soft parts, fossil
                  records of Callianassoidea are usually represented by the chelipeds or fingers. Schweitzer-Hopkins
                  and Feldmann (1997) first described sexual dimorphism in the fossil species of the ctenochelid
                  Callianopsis from the Eocene of Washington. Casadío et al. (2004) also recognized sexual dimorphism
                  in Callianopsis from the Oligocene of Argentina. Mourik et al. (2005) discussed polymorphism
                  in the cheliped of the Late Cretaceous Protocallianassa faujasi, and inferred the possibility of the
                  protandrous hermaphroditism. Schweitzer et al. (2006) described sexual dimorphism in the callianassid
                  Melipal chilensis from the Eocene of Chile. The purpose of the present work is to record sexual
                  dimorphisms in the cheliped of four fossil species of Callianasoidea from the Cenozoic of Japan.
                  Callianopsis muratai (Nagao) is the most dominant decapod species in the Paleogene of northeast
                  Japan. As Schweitzer-Hopkins and Feldmann (1997) has already suggested, Callianopsis muratai
                  and C. elongatodigitata (Nagao) are referred to sexual dimorphism of a single species. Interestingly,
                  statistical study based upon more than 500 specimens indicated that sex ratio of C. muratai was
                  significantly different among several outcrops. Notable pattern of preferential handedness of the major
                  cheliped reported in Schweitzer-Hopkins and Feldmann (1997) and Schweitzer et al. (2006) were
                  not recognized both in male and female. The early to middle Miocene Callianopsis titaensis (Nagao)
                  exhibits similar sexual dimorphism in the morphology of the chelipeds. Although Karasawa (1989)
                  was synonymised Callianopsis shikamai (Imaizumi) with C. titaensis, our examination shows that
                  C. shikamai is female of C. titaensis. Two callianassid species, Neocallichirus bona (Imaizumi) from
                  the early and middle Miocene, and Podocallichius grandis (Karasawa and Goda) from the middle
                  Pleistocene to Holocene, exhibit distinct sexual dimorphisms in the morphology of chelipeds.
                  This work was partly supported by the Fujiwara Natural History Foundation to H. Kato.

                                                                             69




General (poster).indd 69                                                                                                                    09.8.11 9:10:39 AM
                    General Contributed Papers (posters)

                    [GP-33] Population structure in the commercially important mudshrimp Austinogebia
                           edulis in Taiwan and Hong Kong revealed by mitochondrial and microsatellite
                           DNA markers
                            Feng-Jiau Lin1), Hung-Du Lin1), Tin-Yam Chan2), Ping-Han Chung1), Tzen-Yuh Chiang1)
                               1)
                                Department of Life Sciences, National Cheng Kung University, Taiwan; 2) Institute of Marine Biology, National
                               Taiwan Ocean University, Taiwan

                    Populations of mudshrimp, Austinogebia edulis, in the intertidal mud flat of western Taiwan have
                    severely declined due to habitat destruction and overfishing in the past decades. We explored
                    population genetic structure of this species sampled at four study sites in Central West Taiwan and
                    Hong Kong, by using both mitochondrial and nuclear SSR markers. The partial mitochondrial Cyt-b
                    and COI region and nine microsatellite loci were sequenced and analyzed. High haplotype diversity
                    (h=0.99) and low nucleotide diversity (π=0.046) of mtDNA were detected. High h and low π suggest
                    a bottleneck followed by rapid growth and accumulation of mutations. In addition, the microsatellite
                    data revealed that populations may have experienced recent bottlenecks. The genetic analyses of
                    mtDNA and microsatellite markers identified two lineages corresponding to Taiwan and Hong Kong
                    that were separated by the geological barriers on account of abbreviated larval developments and
                    ocean currents. The approaches revealing low to moderate levels of genetic diversity suggested
                    that populations of Taiwan and Hong Kong are highly structured. Significantly negative Tajima’s D
                    statistics and mismatch distribution analyses suggested that A. edulis population probably experienced
                    population expansion in Hong Kong. Results are also discussed in relation to conservation of this
                    endanger species.




                    [GP-34] Reproductive phenology of the sympatric hermit crabs in Nakagusuku Bay,
                           Okinawa Island, southwestern Japan
                            Ryuta Yoshida, Masayuki Osawa, Euichi Hirose
                               Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Japan

                    Reproductive seasons and some reproductive characters of four intertidal sympatric species of hermit
                    crabs were investigated in two estuarine tidal flats of Nakagusuku Bay, Okinawa Island, southwestern
                    Japan, from November 2007 to October 2008. In our study sites located in subtropical area, females
                    of Pagurus minutus of the Paguridae had clutches from November to April, whereas the other three
                    species of the Diogenidae (Clibanarius longitarsus, Clibanarius striolatus, Diogenes leptocerus)
                    reproduced from March to October. Wada et al. (2005) reported similar reproductive phenology of
                    nine hermit crab species in the temperate shore, and suggested that interspecific variations of the
                    reproductive seasons are determined by allopatric adaptation with phylogenic constraints. The three
                    diogenid species of the present study also had interspecific variations in the period of reproductive
                    peak. Diogenes leptocerus bred from May to October, and more than 90% of the females carried eggs
                    from July to Sepetember. Clibanarius longitarsus and C. striolatus had a bimodal breeding pattern,
                    with the first peak in June (>60% females were ovigerous) and second peak in September and October
                    (ca. 80% and ca. 30% of the females were ovigerous in C. longitarsus and C. striolatus, respectively).
                    The two Clibanarius species may have such a breeding pattern to avoid the breeding peak of the
                    major hermit crab species in our study site, i.e., D. leptocerus. Reese (1968) reported the difference of
                    the breeding peaks between the three sympatric hermit crab species in Hawaii and suggested that the
                    difference was caused by the competition for the food resources between the larvae of the sympatiric
                    species. While the Hawaiian tropical hermit crabs reproduce all year round, the three diogenid species
                    of our study reproduce in the warmer half of the year in the subtropical environment.




                                                                             70




General (poster).indd 70                                                                                                                        09.8.11 9:10:39 AM
                  General Contributed Papers (posters)

                  [GP-35] DNA barcoding of intertidal porcelain crabs (Decapoda: Anomura) in the
                        Ryukyu Islands, southwestern Japan, with some taxonomic implications
                           Masayuki Osawa, Mamiko Hirose, Euichi Hirose
                             Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Japan

                  The crab-shaped anomuran family Porcellanidae is one of the most common crustaceans in shallow
                  waters between warm temperate and tropical areas. In this family, Petrolisthes is the most speciose
                  genus, and many species and individuals inhabit intertidal zones of rocky shores and coral reefs.
                  The use of DNA sequences as taxonomic tags may improve our recognition of species and verify
                  phylogenetic relationships. DNA-barcoding data provide a convenient tool for species identification.
                  In metazoans, partial sequences of the cytochrome oxidase I (COI) gene are often used as the DNA-
                  barcoding. In the present study, we determined partial sequences of the COI gene of species of
                  Petrolisthes and its possible related genera found in the intertidal zones of the Ryukyu Islands,
                  southwestern Japan. The DNA sequences showed large differences in the species examined, and
                  thus they can be used as nametags to distinguish each species. Phylogenetic analyses based on the
                  sequences offer some suggestions on the interspecific relationships of these porcellanid genera. The
                  genus Petrolisthes is divided into seven informal species groups based on the larval morphology. The
                  sequenced species of Petrolisthes include members of the Groups 1, 4, and 7, and Novorostrum species
                  have characters of the Group 1. Our phylogenetic trees indicate that the genus Petrolisthes is not
                  monophyletic and close relationships between the genus Novorostrum and P. japonicus of the Group 1.
                  Petrolisthes unilobatus of the Group 7 situates at the sister clade position of the clade of P. japonicus
                  and Novorostrum species. Zoeas of these species have the characters of the first maxilliped and
                  telson which are not found in larvae of the other porcellanids. Interestingly, P. unilobatus differs from
                  Novorostrum species and P. japonicus in the telsonal setation of the second zoea despite P. unilobatus
                  and P. japonicus are closely similar in the adult morphology.



                  [GP-36] Regional variation in life history traits of the fiddler crab Uca arcuata
                           Misuzu Aoki1), Yoko Watanabe1), Hideyuki Imai2), Mahito Kamada3), Keiji Wada1)
                             1)                                                         2)
                                  Biological Science, Nara Women’s University, Japan;        Biological Science, University of the Ryukyu, Japan;
                             3)
                                  Civil Engineering, University of Tokushima, Japan

                  There have been few studies on geographic variation of life history traits in intertidal crabs. We
                  compared life history traits of the fiddler crab Uca arcuata distributed from Japan to Vietnam, among
                  two temperate localities (Tokushima and Kumamoto, Japan) and one subtropical locality (Okinawajima
                  Island, Japan). Monthly change in population structures have revealed that Okinawajima population
                  has two breeding periods of summer and winter in year, while two temperate populations breed in
                  summer. Maturity was attained at 1 year old in Okinawajima population, while it was two years old in
                  two temperate localities. The maximum body size as well as the minimum body size of breeding crabs
                  were smaller in Okinawajima population than in two temperate populations. Thus, the subtropical
                  population differs from two temperate populations in temporal pattern of reproductive activities.
                  Field observation has found that there exist two types of mating behavior: the surface coupling and
                  the underground coupling. Frequencies of the two types were similar to each other in Tokushima
                  population, whereas in Kumamoto and Okinawajima populations the surface coupling dominated.
                  The body size of a coupling pair was correlated between the sexes in Kumamoto and Okinawajima
                  populations, while it was not in Tokushima population. Thus, Tokushima population differed from
                  Kumamoto and Okinawajima populations in characteristics of mating behavior.




                                                                             71




General (poster).indd 71                                                                                                                            09.8.11 9:10:40 AM
                    General Contributed Papers (posters)

                    [GP-37] Geographic variations in waving display and barricade-building behavior, and
                           genetic population structure in the intertidal brachyuran crab Ilyoplax pusilla
                            Arisa Yamada, Fumiko Furukawa, Keiji Wada
                              Biological Science, Nara Women’s University, Japan

                    Geographic variations in two social behavioral characters, waving display and barricade building, and
                    genetic population structure were examined in the tidal-flat inhabiting dotillid crab Ilyoplax pusilla
                    (de Haan, 1835), in six localities between the northern and southern limits of its distributional range
                    (four localities from the Japanese mainland and two southern localities from the Ryukyu Islands).
                    Although waving motion followed the same lateral-circular pattern in all of the local populations,
                    cheliped-extension at the wave peak was most prominent in the Yakugachi River population (near
                    the distribution’s southern limit in the Ryukyu Islands), followed by Haneji Inlet (the southern limit
                    in the Ryukyu Islands) and four localities on the Japanese mainland in that order. The frequency of
                    barricade building showed a similar trend, namely lowest in Yakugachi River, followed by Haneji Inlet
                    and the four mainland localities. Genetic relationships among the six local populations revealed that
                    the two southernmost populations (Yakugachi River and Haneji Inlet), particularly the former, differed
                    significantly from the mainland populations. The similar geographic trend between social behavior and
                    genetic structure suggests a relationship at some level between the two.




                    [GP-38] Burrow morphology of two ghost crabs, Ocypode ceratophthalma and O. sinen-
                           sis in foreshore, backshore, and dune subenvironments of the Irino Coast, south-
                           western Japan
                            Koji Seike1), Masakazu Nara2)
                              1)                                                                        2)
                               Department of Earth and Planetary Science, University of Tokyo, Japan;        Department of Natural Sciences,
                              Kochi University, Japan

                    Burrow morphology of the ghost crabs Ocypode ceratophthalma and O. sinensis were examined using
                    plaster casting in foreshore, backshore and dune subenvironments of the Irino Coast, southwestern
                    Japan. Ornaments of the burrow surface were also recorded. In this study, a total of 115 near-complete
                    burrow casts were collected. Diameter of main shaft, depth, and total length of the burrows varied
                    14 to 40 mm, 12 to 89 cm, and 8 to 143 cm, respectively. The burrows can be classified into three
                    morphological types: unbranched, branched, and multi-branched. Although the burrow diameters are
                    almost simillar among the three subenvironments, the burrows increased in length and complexity
                    from foreshore to dune. Surfaces of most of the burrow casts are relatively smooth, except for their
                    floor surfaces, which are covered with closely spaced, hemispherical knobs (footprints of the crab)
                    about 5 mm in diameter. However, strongly ornamented surfaces, characterized by the presence of
                    groups of ridges, each of which is up to 40 mm long (scratch marks formed by excavating activity of
                    the crab), are seen on sides and roof of the shafts in 57 burrow specimens. The sculptural patterns are
                    characteristically seen near the distal end of the burrow.




                                                                           72




General (poster).indd 72                                                                                                                       09.8.11 9:10:40 AM
                  General Contributed Papers (posters)

                  [GP-39] Genetic population structure of the brackish water crab Deiratonotus japonicus
                         (Camptandriidae)
                           Masako Kawane1), Katsutoshi Watanabe2), Shin-Ichi Iwaguchi1), Keiji Wada1)
                             1)
                                  Biological Science, Nara Women’s University, Japan; 2) Kyoto University, Japan

                  Coastal animals living in estuaries and enclosed embayment are expected to show greater genetic
                  population differentiation owing to the habitat feature. Genetic population structure of the camptandriid
                  crab Deiratonotus japonicus (Sakai, 1934) that occurs in restricted upstream brackish water areas of
                  southwestern Japan was analyzed by sequence data from the mitochondrial DNA COI region. Nine
                  of 45 local population pairs of D. japonicus showed significant genetic differentiation in 210–1100
                  km scale which is fine-grained structure distinctive from other littoral crabs. This significant genetic
                  differentiation showed positive correlation between geographic and genetic distances, suggesting
                  isolation by distance. Populations of D. japonicus along the coast of the Kii Peninsula, western Japan,
                  were moreover studied on fine-scale genetic relationship and gene flow with mitochondrial DNA and
                  microsatellite DNA variations. Sequence variation of the mitochondrial DNA COI region has detected
                  two major genetic breaks in the peninsula. Analysis of newly developed microsatellite loci revealed
                  that there was little gene flow among respective populations, with small effective population size.
                  Thus, each local population of D. japonicus was considered to have been maintained mainly by self
                  retention of the larvae.




                  [GP-40] Description of gill-cleaning setae of Japanese six Macrophthalmus crabs
                           Takashi Matsuoka1), Hiroshi Suzuki2)
                             1)                                                                                    2)
                              United Graduate School of Agricultural Science, Kagoshima University, Japan;              Faculty of Fisheries,
                             Kagoshima University, Japan

                  Gills of crabs are cleaned by the setae on the epipods of the first to third maxillipeds. Macrophthalmus
                  species inhabited intertidal area is occupied with various activity (feeding, social behavior and
                  holing) on land during in lowtide. The gill-cleaning setae of Macrophthalmus species have not been
                  described. In this study, the authors described the gill-cleaning setae of Macrophthalmus species. Six
                  specimens of genus Macrophthalmus (M. abbreviatus, M. convexus, M. serenei, M. japonicus, M.
                  banzai, M. pacificus) in 70% ethyl alchol (EtOH) were used for this study. The epipods of the first
                  to third maxillipeds were cut from the body and dehydrated in EtOH series. After dehydration, the
                  specimens of M. japonicus in EtOH were displaced in mixtures of tri-butyl alchol (t-BuOH) and EtOH
                  (tBuOH:EtOH=1:1, 2:1). Specimens in absoluted t-BuOH were refrigerated, then freeze dried (VFD-21
                  t-BuFreeze Dryer). Other specimens were dried naturally. Specimens were mounted on aluminum
                  stubs, coated with gold (Eiko ION COATER IB-2) and viewed in SEM (Hitachi S4100H) and ESEM
                  (Japan FEI XL30). Setae were represented in five types which were digitate scale setule setae, mixed
                  digitate scale setule with setule setae, serrate setae, anchor setae, and simple setae. Anchor setae were
                  mainly three types which were half anchor setae (with singly recurved outgrowths), full anchor setae
                  (with oppositely recurved outgrowths), and half-full anchor setae (with half anchors and full anchors).
                  Some these anchor setae armed with setules or digitate sacale setules. In subgenus Macrophthalmus,
                  half anchor setae with one row of anchors and simple tip were found on the epipods of the first and
                  third maxillipeds. The above setae were compared with other examined crabs. Based on the above
                  results, the authors discussed feature and function of the gill-cleaning setae.




                                                                               73




General (poster).indd 73                                                                                                                        09.8.11 9:10:40 AM
                    General Contributed Papers (posters)

                    [GP-41] Mating system in the mud crab Scylla serrata, assessed using microsatellite
                           makers
                            Reiko Fuseya1), Shigeki Dan2)
                               1)                                                                                 2)
                                Seikai National Fisheries Research Institute, Fisheries Research Agency, Japan;        Tamano Station, National
                               Center for Stock Enhancement, Fisheries Research Agency, Japan

                    The mud crab Scylla serrata inhabits brackish waters such as mangrove areas and estuaries, and
                    is found widely in the Indo-Pacific Ocean. Sustainable management of S. serrata is necessary
                    because this species is important as a fisheries and aquaculture resource in the tropical region. Stock
                    enhancement and aquaculture of the mud crab have been examined in recent years. Copulation in
                    the mud crab occurs in autumn during the period immediately following female molting when their
                    carapaces are still soft. In this study, genetic parentage analysis using microsatellite markers was used
                    to investigate the mating system of the mud crab in the wild. Mature female crabs, probably after
                    mating, were caught in autumn and reared until spawning and hatching in spring. Genomic DNA was
                    extracted from the muscles of the walking legs and spermathecae were collected from the females and
                    the first zoeae after hatching. The mating system was analyzed using five polymorphic loci developed
                    in our previous study. PCR products were analyzed using an ALF Express DNA Sequencer and
                    fragment analysis software. The genotype data for all loci indicated that each female copulated with
                    only one male. This genetic parentage analysis provides an insight into the mating system of S. serrata
                    and suggests the prevalence of monogamy in natural populations of this species. Having revealed the
                    mating system in S. serrata, we accordingly recommend that more than one female should be used for
                    seed production in hatcheries.




                    [GP-42] Growth pattern and total life span of the Japanese mitten crab Eriocheir japon-
                           ica in Fukuoka Prefecture, Japan
                            Satoshi Kobayashi
                               Faculty of Agriculture, Saga University, Japan

                    Size composition and growth pattern of Japanese mitten crab Eriocheir japonica (Varunidae) in natural
                    population was investigated and the total life span of this species was estimated. Crabs were collected
                    by hand-held nets in the Saigo River and adjacent seacoast in Fukuoka Prefecture, Japan. Dynamics
                    of carapace width (CW) frequency distribution was analyzed and cohorts in each time were identified
                    from the polymodal size distribution using the Bhattacharya’s method in FISAT II package. In the
                    lower tidal river and seacoast area (reproductive area of the mitten crab), only adult crabs composed
                    of at least four cohorts were collected; average size in each cohort was 38.0, 46.9, 55.1 and 65.6 mm
                    CW collected during autumn, 1996 - summer, 1997, and 38.6, 45.6, 54.9 and 62.0 mm CW during
                    autumn, 1997 - summer, 1998. Meanwhile, from the monthly data for 29 months (January, 1997 - May,
                    1999) collected from the upper tidal to the lower freshwater area (growth area of the mitten crab), two
                    cohorts which settled in different season (autumn and early summer) were confirmed in each year.
                    Both cohorts reached adult size (ca. 35 mm < CW and 45 mm < CW in average) in the autumn in 2
                    years old after settlement. Therefore, it can be estimated that adult crabs occurred in the tidal area are
                    mainly composed of two cohorts of 2 years old (ca. 24 and 29 months) and two cohorts of 3 years old (ca.
                    36 and 41 months) after settlement. By combining the data of duration of larval phase (ca. 2 weeks - 3
                    months) and duration of reproduction for each adult crab (ca. 3 - 6 months) with the present result, the
                    total life span of E. japonica can be estimated; that is mostly 2 years (ca. 30 months) – 4 years (ca. 50
                    months) after hatching in the Fukuoka population.




                                                                                74




General (poster).indd 74                                                                                                                          09.8.11 9:10:40 AM
                  General Contributed Papers (posters)

                  [GP-43] Reproduction of the oyster pea crab, Zaops ostreum (Say, 1817) (Crustacea:
                         Brachyura: Pinnotheridae)
                           Juan Bolaños, Jose L. Palazón-Fernández, Jesus E. Hernández, Regulo López
                             Universidad de Oriente, Venezuela

                  The object of the present work was to supply basic information about the reproductive biology of
                  Zaops ostreum living in symbiosis with the oyster Crassostrea rhizophorae Guilding, 1828, in relation
                  to sex ratio, spawning season and fecundity. Samples were taken monthly during a one year period.
                  Carapace length (CL) and width (CW) and total (TW) and egg mass (EMW) weight were measured. A
                  total of 215 specimens (155 females and 60 males), ranging from 1.03 to 8.81 mm CL were examined.
                  Sex ratio did not differed from 1:1 ratio during most of the sampling period except in November
                  2007-January 2008 and March-April 2008 when males were scarce or absent. Approximately 50 % of
                  the population matured at 5.12 and 2.53 mm CL for females and males, respectively. Mature specimens
                  were present throughout the year, indicating that the spawning is continuous. Fecundity ranged from
                  32 to 9232 eggs with a mean of 3095.29 ± 280.78 eggs, and was related to body and egg mass weight.
                  Length-weight relationship for adult sexes was different. Males showed negative allometry while
                  females showed isometry.




                  [GP-44] Morphological changes after puberty molt of majoid decorator crab, Hyastenus
                         diacanthus (De Haan) from Kyushu, southwest Japan
                           Naoya Ohtsuchi1), Masatsune Takeda2)
                             1)
                              Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan; 2) Department of Zoology,
                             National Science Museum, Tokyo, Japan


                  Many crabs of the family Majidae s.l. experience a puberty molt with the onset of secondary sexual
                  characters such as chelae enlargement in male and abdomen expansion in female. Morphological
                  changes after puberty molt are more extensive in majoid species than in other crab groups.
                  Morphological maturity of crabs can be estimated indirectly through making allometric equations. It
                  is most important to treat pre- and post-puberty specimens separately, but there are no recent studies
                  working on direct comparison of morphological differences between before and after practical puberty
                  molt. Present study reports on morphological changes after practical puberty molt in rearing condition
                  of decorator crab, Hyastenus diacanthus (De Haan) of the family Epialtidae. Growth rate of crabs
                  based on many specimens from Kyushu is supposed to be ca. 1.200-1.300, and those of front width
                  (FW) and post-rostral carapace length are relatively constant in both sexes. Comparing FW/CW ratio,
                  male carapace slightly got broader backwards than in female (0.2976 to 0.2823 vs. 0.2795 to 0.2576).
                  Rostrum length extended more in male (1.410) than female (1.117). Maximum abdomen width
                  expanded more strongly in female (1.762) than in male (1.274). Male abdomen, however, also changed
                  in shape. Morphology of orbital hiatus and basal antennular article did not change between before and
                  after puberty molt or sexes. Male cheliped size more increased in length (1.725), width (2.718), depth
                  (2.767) and dactylus length (2.053) than in female (1.321, 1.226, 1.122, and 1.225), with change in
                  form. First ambulatory legs elongated more in male (1.568) than the second (1.417) or female (1.403
                  and 1.397). Male first propodus and female first dactylus showed higher growth rate (1.667 and 1.648).
                  Morphology of male G1 was remarkably modified and female genital opening also changed slightly in
                  shape.




                                                                           75




General (poster).indd 75                                                                                                                     09.8.11 9:10:41 AM
                    General Contributed Papers (posters)

                    [GP-45] Moult cycle characterization in Maja brachydactyla larvae (Brachyura, Maji-
                           dae), reared in the laboratory
                              Guillermo Guerao1), Guiomar Rotllant1), Klaus Anger2)
                                 1)
                                  IRTA, Unitat de Cultius Experimentals, Spain; 2)Alfred-Wegener-Institut für Polar- und Meeresforschung, Bi-
                                 ologische Anstalt Helgoland, Germany
                    The moulting cycles of all larval stages (zoea I, zoea II, megalopa) of the spider crab Maja
                    brachydactyla Balss 1922 were studied in laboratory-reared individuals. Changes in the epidermis and
                    cuticle were photographically documented in daily intervals and assigned to successive stages of the
                    moulting cycle (based on Drach’s classification system). Stage characterizations were mainly based on
                    microscopical examination of integumental modifications in the telson, using epidermal condensation,
                    apolysis, the degree of epidermal retraction, and morphogenesis (setogenesis) as criteria. In the zoea
                    II and megalopa, the formation of new setae was also observed in larval appendages including the
                    antenna, maxillule, maxilla, second maxilliped, pleopods, and uropods. As principal stages within
                    Table 1. Maja brachydactyla. Duration of the moult cycle in larval stages reared at 18 ºC.
                                                                                                               the zoea I moulting cycle, we describe
                       Age                                                                                     postmoult (A-B), intermoult (C), and
                      (days) Larval stage Moult stage            Morphological observations on telson
                                                                                                               three premoult stages (D0, D1, D2). In
                        0         Zoea I         A-B       spongy epidermis                                    the zoea II and megalopa, stages stages
                        1                         C        condensation of epidermal tissues
                        2                      0
                                                  D        apolysis                                            D1 and D2 had to be combined, because
                        3
                        4
                                               1
                                                  D
                                                  D
                                                           setogenesis
                                                           appearance of new cuticle
                                                                                                               morphogenesis (the main characteristic
                        5
                                               2
                                                  E        moulting                                            of stage D1) was unclear in the telson
                        0        Zoea II         A-B       spongy epidermis                                    and did not occur synchronically in
                        1                         C        condensation of epidermal tissues                   different appendices. The duration of
                        2                         D        apolysis
                        3
                                               0
                                                           advanced apolysis                                   successive moulting stages within each
                        4                                  branches with all spines and setae degenerate
                        5                         D        appearance of new cuticle                           larval instar and major morphological
                                                                                                               changes in the telson are summarized in
                                               2
                        6                         E        moulting

                        0       Megalopa         A-B       spongy epidermis                                    Table 1. The knowledge of this sequence
                        1
                        2
                                                  C
                                                  D
                                                           condensation of epidermal tissues
                                                           apolysis
                                                                                                               can be used as a tool for the evaluation
                        3
                                               0
                                                                                                               of the developmental state within larval
                        4                                  advanced apolysis
                        5                                  maximum retraction of the epidermis                 stages, which may facilitate future
                        6
                        7
                                               2
                                                  D
                                                  E
                                                           appearance of new cuticle
                                                           moulting
                                                                                                               studies on crab aquaculture.




                    [GP-46] Trip to laying eggs of the red hand crab
                              Taichi Kojima
                                 Hiroshima University, Japan

                    The red hand crab descends from the mountains to lay eggs in the summer on nights near the full moon
                    and new moon of each month when the tide is highest. Most crabs that go all the way to the shore
                    shore are female. Males wait at the bottom of the mountains until the females return from egg-laying
                    and then copulate when they return. The population demogvaphics of the crabs were recorded for nine
                    years. The objective of this research was to find the relationship between the crab male/female ratio
                    which traveled all the way to the shore and temperature and weather conditions present in the area.
                    METHOD: From July 2000 to September 2007 data was recorded in Amakusa City Ariake Town near
                    Shimotsuura River in three separate locations. Each lacation had an area of 1 m2. One was located near
                    the shore, one near the mountains, and one between the shore and the mountains. Data was recoded in
                    several three day periods: the day before, the day after, and the day before a full moon or new moon.
                    In each of the areas, the number of male and female crabs present was recorded in addition to the days
                    weather conditions and temperature and weather it was a full or new moon. Finally, the changes in the
                    populations of the crabs were noted as well before all of the factors were taken into consideration for
                    the research.



                                                                                   76




General (poster).indd 76                                                                                                                                  09.8.11 9:10:41 AM
                  General Contributed Papers (posters)

                  [GP-47]     Effectiveness of lipofuscin as an age marker in the xanthid crab Leptodius
                            exaratus
                           Ryuji Watanabe, Katsuyuki Hamasaki, Carlos A. Strüssmann, Masashi Yokota, Seiichi
                           Watanabe
                             Tokyo University of Marine Science and Technology, Japan

                  Age determination had been difficult for crustacean species because they have no hard parts such
                  as otoliths, scales or vertebral bones which can be used in aging as in fish. However, a remarkable
                  progress in aging technology for crustaceans has been made recently: the use of autofluorescent
                  pigment lipofuscin as an age marker. This study aims to examine the effectiveness of lipofuscin as
                  an age marker in the xanthid crab Leptodius exaratus. Samples of L. exaratus were collected on a
                  monthly basis from June to August, 2007 on rocky shores in Banda, Chiba Prefecture, Japan. Sampled
                  crabs were fixed in 10% neutral formalin solution and the carapace width was measured using a digital
                  caliper. The brain was removed from each crab and paraffin sections were prepared for detecting the
                  autofluorescent pigment (lipofuscin) under a fluorescent microscope. The olfactory lobe cell mass
                  (OLCM) was selected for image analysis to determine the lipofuscin accumulation by the crabs
                  because preliminarily observations of the brain sections showed that the highest density of lipofuscin
                  was found in the OLCM. Image analysis was performed using digital images and the software Image-
                  Pro. The relative amount (% area) of lipofuscin in each individual was calculated as a percentage of
                  the area (number of pixels) of the OLCM covered by lipofuscin fluorescence pixels. The value for each
                  individual is the geometric average of measurements in 5 sections. The range in carapace width and
                  lipofuscin accumulation of the crabs were 8.1–31.7 mm and 0.0408–0.3961%, respectively. Lipofuscin
                  accumulation tended to increase with increasing carapace width of the crabs. Lipofuscin accumulation
                  frequency distribution was tentatively assigned to four age groups by the Hasselblad method and
                  lipofuscin showed constant accumulation rate in each estimated age group. From these results, it is
                  thought that Lipofuscin is effective as age marker of Crustacea.




                  [GP-48] Two extra dactyls on the left chela of a male snow crab, Chionoecetes opilio
                           Hajime Matsubara, Yoshifumi Horie, Ayaka Chiba, Daisuke Iwata, Yuta Fukuoka, Takamasa
                           Suzuki
                             Department of Aquatic Biology, Tokyo University of Agriculture, Abashiri, Japan

                  The abnormal chela had been reported in some kinds of crabs. In the present study, we informed the
                  male snow crab (Chionoecetes opilio) with two extra dactyls on the left chela which was caught from
                  Abashiri Hokkaido, Japan on the 22 April 2009. The two extra dactyls on the left chela were observed
                  near the inner proximal portion of the original immovable finger. Interestingly, these additional two
                  extra dactyls were smaller than original dactyls. However, these two extra dactyls were a movable and
                  an immovable finger, respectively. Albeit rare, we have observed that the functional two extra dactyls
                  on the left chela of the male snow crab. We hypothesized that this two extra dactyls had been occurred
                  by hypertypic regeneration of the wounded dactyl.




                                                                           77




General (poster).indd 77                                                                                                   09.8.11 9:10:41 AM
                    General Contributed Papers (posters)

                    [GP-49] Basic studies on the mud crab (genus Scylla de Haan, 1833) fishery in Yap Is-
                           land
                            Akihiro Kawada, Masashi Yokota, Carlos A Strüssmann, Seiichi Watanabe
                              Tokyo University of Marine Science and Technology, Japan

                    The mud (or mangrove) crabs of the genus Scylla de Haan, 1883 are important fisheries resources in
                    Yap Island. Anecdotal reports suggest the presence of 2-3 species of mud crabs in the island but this
                    has never been clarified. The purposes of this study were to identify the Scylla species and to review
                    the current status of its fishery in Yap Island. Species identification was based on 51 individuals
                    captured between August and October, 2003 using the morphological identification key of Keenan et
                    al., 1998. The main points for identification of Scylla species are the morphological features of the
                    carpus and carapace. The fishing methods and status of marketing were studied through field survey
                    and interviews with fishermen. Two morphological features of the carapace (ratio of the frontal
                    medium spine height to frontal width and ratio of the carapace frontal width to internal carapace
                    width) agreed with those for S. serrata whereas the ratio of the inner to outer carpus spines showed
                    intermediate values between those of S. serrata and S. tranquebarica. The most common fishing
                    methods for mud crab are catching by hand or using a hook, traps, and gill-nets. The first two methods
                    are mostly used in the mangrove swamp during low tide whereas the latter two methods are used
                    underwater inside or outside mangrove area. Only a few elders carry on the tradition to make crab traps
                    using the pitcher plant (Nepenthes sp.) and these skills are being lost. Crabs are sold directly by the
                    fishermen to restaurants, hotels, and foreign residents but the income afforded by mud crab catching is
                    highly variable (US$ 0-300/month). Further studies are needed for accurate species determination, for
                    the management of Scylla resources, and for guaranteeing a stable income to fishermen from mud crab
                    fisheries.




                    [GP-50] Ovipositional behaviour of two xanthid crabs, Atergatis integerrimus (Lamarck,
                           1801) and A. subdentatus De Haan, 1833 (Decapoda, Brachyura, Xanthidae) in
                           captivity
                            Hironori Tanaka1), Toshiro Saruwatari2)
                              1)
                                   Oarai Aquarium, Japan; 2) Ocean Research Institute, the Univeristy of Tokyo, Japan

                    Ovipositional behaviour of two xanthid crabs, Atergatis integerrimus and A. subdentatus were
                    observed in the laboratory. Female A. integerrimus was reared in an aquaria with approximately 1
                    cm deep sand on the floor. Female A. subdentatus was reared in an aquaria without sand. Prior to
                    spawning, the female of both species exhibited similar behaviour. The carapace and the posteriorly
                    extended abdomen was suspended parallel to the aquarium floor, supported by the chela, first and
                    second pereopods. This position formed a semi enclosed space between the carapace and the aquarium
                    floor. The paired exopods of the first to fourth pleopods spread out horizontally to the lateral sides
                    of the abdomen. The Adhesive eggs were spawned onto the aquarium floor, excreted from the two
                    gonopores. The eggs sank into a depression under the abdomen. The female attached the eggs to the
                    ovigerous setae of the endopods by moving it back and forth. After most of the eggs were collected
                    and attached to the ovigerous setae, female folded its abdomen and began nursing their eggs. Some
                    of the eggs did not attach to the ovigerous setae of each female. Not all the eggs of A. integerrimus,
                    which was reared with 1 cm thick sand on the aquaria bottom, did not adhere to ovigerous setae. This
                    was probably because the sand was not deep enough for the female to collect eggs using the ovigerous
                    setae, by picking up the eggs together with the sand. In A. subdentatus, which was kept in an aquaria
                    without sand on the bottom, adhesive eggs attached to the glass bottom, most eggs did not adhere to
                    the ovigerous setae and those that did fell off later on.




                                                                               78




General (poster).indd 78                                                                                                      09.8.11 9:10:42 AM
                  General Contributed Papers (posters)

                  [GP-51] Larval development of Atergatis integerrimus (Lamarck, 1801) (Decapoda,
                        Brachyura, Xanthidae) described from laboratory-reared material
                           Hironori Tanaka1), Toshiro Saruwatari2), Takashi Minami3)
                             1)
                               Oarai Aquarium, Japan; 2) Ocean Research Institute the Univeristy of Tokyo, Japan; 3) Faculty of Agriculture,
                             Tohoku University, Japan

                  An ovigerous female Atergatis integerrimus was collected from Ise bay in Mie prefecture on 25
                  February 2009. The individual was transported to the Oarai Aquarium, and reared in an aquarium.
                  First zoeas hatched early in the morning on 1 April 2009 and they were reared in circular 30 l plastic
                  tanks. In order to determine the number of the specie’s larval stages and duration, 100 zoeas were
                  kept in 2000 ml glass beakers. One-third of the water in the tank was changed daily and salinity and
                  water temperature were kept at 33–35 and 24.2–25.5 ℃ , respectively. First and second zoeas were fed
                  cultured rotifer Brachionus plicatilis and third zoeas were fed newly hatched Artemia sp. nauplii. The
                  zoeal specimens were fixed in buffered 5 % formalin and later transeferred to 80% EtOH. Dissections
                  and measurements were made under a stereomicroscope. Observations and drawings were made with a
                  microscope equipped with a drawing tube. At least five individuals of each zoeal stages were examined
                  and measured. Rearing of larvae terminated at the third zoeal stage. Duration of each zoeal stages
                  were 4–5 days. The zoea has one rostral, one dorsal, and a pair of lateral spines. The first zoea had
                  sessile eyes and the number of abdomen were 5. The second zoea had stalked eyes, third maxilliped
                  and rudimentary buds of pereiopods. The number of abdomen was 6 and pleopod buds present on 2
                  –6 omites in the third zoea. Zoeas of A. integerrimus differed from previously described zoeas of
                  congeners by the combination of following characters: dorsal carapace spine spinulate and rostral spine
                  nearly as long as protopod antenna in the first zoea; rostral spine longer than length of the protopod of
                  antenna in the third zoea.



                  [GP-52] First stage zoeal morphology of the Camptandriidae Stimpson, 1858 (Decapoda,
                         Brachyura, Ocypodoidea)
                           Jose A. Cuesta1), Paul F. Clark2), Peter K. L. Ng3)
                             1)
                              Instituto de Ciencias Marinas de Andalucía (CSIC), Spain; 2) Department of Zoology, The Natural History
                             Museum, London, England; 3) Tropical Marine Science Institute and Department of Biological Sciences,
                             National University of Singapore, Republic of Singapore

                  The intertidal silt crabs of the family Camptandriidae Stimpson, 1858 (Ocypodoidea Rafinesque,
                  1815) currently comprises 39 species assigned to 19 genera (Ng et al., 2008). Of these taxa, the zoeal
                  morphology is only known for four camptandriids: Deiratonotus cristatum (described by Terada, 1979
                  as Paracleistostoma cristatum), Manningis arabicum, Nasima dotilliformis and Serenella leachii. For
                  the present study, the first zoeal stages of Baruna triganulum, B. minuta, Ilyogynis microcherium and
                  Paracleistostoma depressum, were hatched from ovigerous females and are described for the first time.
                  In addition, the first zoeae of M. arabicum, N. dotilliformis and S. leachii, described by Al-Khayat
                  and Jones (1996), are re-examined and new characters provide additional insights to their systematics.
                  The larval characters of all these species are compared and the results indicate that there is a suite of
                  reliable characters that can distinguish camptandriid first zoeae from those of all other Ocypodoidea.
                  The known camptandriid larvae, however, appear to be clustered into two morphogroups on the basis
                  of the abdominal morphology.




                                                                            79




General (poster).indd 79                                                                                                                       09.8.11 9:10:42 AM
                    General Contributed Papers (posters)

                    [GP-53] Larval occurrence and distribution of swimming crab, Charybdis japonica
                          Milne Edwards, 1860 off Yeonpyeong-do near Korean coast in the Yellow Sea
                            Myoung-Ho Sohn1), Miyoung Song1), Hakjin Hwang1), Yang-Jae Im1), In-Ja Yeon1), Wongyu
                            Park2)*, Chae Woo Ma2), Jae-Won Kim3)
                              1)
                               West Sea Fisheries Research Institute, Korea; 2) Dept. of Marine BioTechnology, Soonchunhyang University,
                              Korea; 3) Dept. of Marine Life-Science, Gangwon Provincial College, Korea

                    Larval occurrence and distribution of swimming crab, Charybdis japonica Milne Edwards, 1860 and
                    sea surface temperature (SST) were investigated off Yeonpyeong-Do near Korean coast in the Yellow
                    Sea. C. japonica larvae were monthly collected at 15 stations from early June to late October in 2006
                    and 2007. Bongo net with 303 mesh was deployed once with a double oblique tow. No larvae were
                    caught in June in both years. Zoea I (84%) was predominated in late July in 2006 and early August in
                    2007. However, during the entire sampling periods in both years, megalopal stage was most abundant:
                    92.7% in 2006 and 78.4% in 2007. The abundance of megalopa was the highest at all stations in
                    late August in both years. In 2006, SST increased from 16.5 °C in June to 24.7 °C in September and
                    decreased to 20.5 °C in October. In 2007, SST SST increased from 16.7 °C in June to 24.9 °C in
                    August and decreased to 21.6 °C in October. The timing of larval hatching of C. japonica may be
                    related to the timing of phytoplankton bloom in the study area. We cannot definitely state where C.
                    japonica larvae grow from the study results. However, C. japonica larvae appear to have hatched
                    within our study sites and have been advected into our study sites after larval growth. The pattern of
                    distribution of larval stages in our study area was similar to the pattern what has been reported from
                    the coastal waters where crab larvae are advected.




                    [GP-54] Preliminary phylogenetic analysis of the Podotremata Guinot (Decapoda:
                          Brachyura) with emphasis on the fossil families
                            Hiroaki Karasawa1), Carrie E. Schweitzer2), Rodney M. Feldmann3)
                              1)
                                   Mizunami Fossil Museum, Japan; 2) Kent State University Stark Campus, USA; 3) Kent State University, USA

                    The Podotremata (Crustacea: Brachyura) contains 11 Recent and 18 fossil families. In the most
                    recent work, the monophyly of the Podotremata was questioned based upon phylogenetic analysis
                    (Ahyong and O’Meally, 2004; Brösing et al., 2007; Ahyong et al., 2007). Phylogenetic analysis of
                    the Podotremata including all Recent and 15 fossil families was performed using adult morphological
                    characters. Additionally, two enigmatic fossil genera, Oxythyreus and Basinotopus, were also included.
                    The analysis also included three eubrachyuran families as ingroup taxa to analyze the possible sister
                    group relationships of the podotreme families. Forty-seven characters were used, the analysis was
                    conducted using PAUP*4.0b10 and MacClade 4,08 (OSX), and Bremer support was obtained using
                    constraint trees generated by MacClade and analyzed using PAUP.* The results of the analysis
                    confirm many recent hypotheses about the Podotremata and suggest that further subdivisions are
                    necessary. The Podotremata is clearly shown to be paraphyletic, consisting of ten major clades. The
                    earliest known fossil family Eocarcinidae is the most basal, followed by the Homolodromioidea, the
                    clade (Glaessneropsoidea + Dromioidea), the Homoloidea, the Torynommatidae, Etyidae, the clade
                    (Necrocarcinidae + Camarocarcinidae + Cenomanocarcinidae + Palaeocorystidae + Raninoidea), the
                    Ibericancridae, the Cyclodorippoidea, and the more derived, Dakoticancridae + Eubrachyura clade.
                    The subdivisions proposed by Guinot (1977), Ahyong et al. (2007), and Guinot et al. (2008), are
                    not supported. The basic superfamily-level classification currently in use is supported, although two
                    families, Torynommatidae and Ibericancridae, need to be given full superfamily status. Oxythyreus is
                    derived as the sister group to the Glaessneropsidae + Longodoromitidae clade and Basinotopus is the
                    sister to the Dromioidea clade. Both genera may belong to a new family. This work was supported by
                    NSF grant EF-0531670 to Feldmann and Schweitzer.




                                                                               80




General (poster).indd 80                                                                                                                      09.8.11 9:10:42 AM
                  General Contributed Papers (posters)

                  [GP-55] Phylogeny of the sand crabs (Brachyura: Thoracotremata: Ocypodoidea) and
                         related families based on nuclear and mitochondrial gene sequences
                           Ming L. Tsang2), Richard B. Landstorfer1), Joelle C.Y. Lai3), Peter K.L. Ng3), Ka-Hou Chu2),
                           Christoph D. Schubart1)
                             1)
                              Biologie 1, University of Regensburg, Germany; 2) Department of Biology, The Chinese University of Hong
                             Kong, Hong Kong, China; 3) Department of Biological Sciences, National University of Singapore, Singapore

                  The so-called sand crabs of the superfamily Ocypodoidea are common on sandy shores, mudflats,
                  mangroves and even freshwater habitats. With eight recognized families, 56 genera and 314 species,
                  they are a relatively large group and exhibit highly diverse morphological forms. They can be very
                  common in intertidal habitats and play a key role in the ecology (e.g. nutrient recycling). There have
                  been many studies of ocypodoid crab taxonomy and phylogeny using adult and larval morphology,
                  as well as molecular data. Some of these studies deal with intrageneric relationships; others reveal
                  that some of the ocypodoid families defined or the superfamily as a whole might not represent a
                  monophyletic assemblage. Thus, it appeared necessary to incorporate a more comprehensive data
                  set and more molecular markers in order to reconstruct a well-resolved phylogeny of the sand
                  crabs and to lay the foundation for a phylogenetic classification scheme. In the present study, we
                  reconstruct the phylogeny of Ocypodoidea and potentially related families using molecular markers
                  from the mitochondrial (16S and 12S rRNA) and nuclear genomes (enolase, NaK and GAPDH).
                  The topology inferred from the combined dataset (~2,500 bp) is well supported in many important
                  nodes and strongly suggests the polyphyly of both Ocypodoidea and Grapsoidea as currently defined,
                  whereas most families are relatively well supported. These results are largely congruent with previous
                  molecular phylogenetic studies based solely on mitochondrial DNA and support merging ocypodoid
                  and grapsoid families under a single taxon within the Thoracotremata. New hypotheses concerning the
                  evolution of the Ocypodoidea are also proposed.



                  [GP-56] Molecular phylogeny of Xanthoidea sensu Ng et al. (2008), with emphasis on
                         the subfamilies of Xanthidae
                           Brent P. Thoma, Darryl L. Felder
                             Department of Biology, University of Louisiana at Lafayette, USA

                  Taxonomic composition and phylogenetic relationships of the superfamily Xanthoidea have long
                  been debated. Particularly problematic has been the composition of the family Xanthidae. In the
                  present study we utilize five molecular loci (18S, H3, 16S, 12S, and COI) to examine the superfamily
                  Xanthoidea sensu Ng et al. (2008) to determine if the group represents a monophyletic clade or an
                  artificial assemblage based on convergence. In addition, we examine the Xanthidae to determine if
                  the family represents a monophyletic clade and if the present subfamily arrangement is supported by
                  molecular phylogenetics. Preliminary analyses are based upon 77 species of 46 genera representing 11
                  xanthoid subfamilies. Results support a monophyletic Xanthoidea sensu Ng et al. 2008, but the family
                  Xanthidae appears to be paraphyletic and many of the presently accepted subfamilies of the Xanthidae
                  appear to be polyphyletic. [supported by U.S. National Science Foundation BS&I grant DEB-0315995
                  & DEB/AToL grant EF-0531603]




                                                                           81




General (poster).indd 81                                                                                                                 09.8.11 9:10:42 AM
                    General Contributed Papers (posters)

                    [GP-57] Phylogenetic analysis of the genus Austinixa (Crustacea, Decapoda, Pinnoth-
                           eridae)
                            Emma Palacios-Theil, Darryl L. Felder
                              Department of Biology, University of Louisiana, USA

                    Taxonomy of the family Pinnotheridae De Haan, 1833, has been the object of numerous recent
                    revisions at the family, subfamily, genus, and species levels. Despite these new insights, many
                    problems remain in taxonomic assignments for species in this family of highly adapted symbionts.
                    The genus Austinixa Heard and Manning, 1997, was erected to accommodate eight shallow water
                    species previously included within the genus Pinnixa. Six of these had been previously known as
                    members of the Pinnixa cristata complex, which included only species from the Western Atlantic. Two
                    more species from Brazil were subsequently added to yield ten species within the genus Austinixa.
                    Phylogenetic analyses have been previously conducted on the genus Austinixa, based on sequence
                    analysis of the 16S and COI mitochondrial genes. This study extends molecular analyses by applying
                    additional mitochondrial and nuclear markers (12S, 18S and Hex3) and also including undescribed
                    species potentially belonging to the genus. Phylogenetic trees are rooted in a new set of outgroup
                    species for insights into relationships with other major clades of the subfamily Pinnothereliinae, to
                    which Austinixa belongs, and to representatives of the other pinnotherid subfamily, Pinnotherinae.
                    Findings suggest that Austinixa patagoniensis is not closely related to its congeners, making generic
                    assignment of this species questionable. The remaining species of Austinixa form two clades, each of
                    which includes both Atlantic and Pacific species, suggesting separation occurred prior to closure of the
                    Panamanian seaway. [supported by U.S. National Science Foundation DEB/AToL grant EF-0531603].




                    [GP-58] Taxonomic studies on Hemigrapsus penicillatus (De Haan, 1837) and H. takanoi
                           Asakura and Watanabe, 2005, based on morphological and molecular characters
                            Sang-kyu Lee1), Hyun Soo Rho2), Hyeyoung Koo3), Won Kim1)
                              1)
                               School of Biological Sciences, Seoul National University, Korea; 2) East Sea Research Institute, Korea Ocean
                              Research & Development Institute, Korea; 3) Department of Biological Science, Sangji University, Korea

                    Hemigrapsus penicillatus is one of the most common crabs around seashore and estuaries of the
                    Korean peninsula. In 2005, Asakura and Watanabe reported H. takanoi as a sibling species of H.
                    penicillatus. To verify the species status of H. takanoi separated from H. penicillatus, we examined
                    the sequence divergences of mitochondrial COI gene of H. penicillatus and H. takanoi. And then, we
                    compared them with those of specimens with mixed characteristics of both species. The molecular data
                    showed that H. penicillatus and the specimens with mixed characteristics constitute a single clade with
                    very high support values, and H. takanoi is separated with H. penicillatus clade. Our results, based
                    on the genetic divergences of mtCOI gene, confirm that H. takanoi is a valid species. The specimens
                    with mixed characteristics are considered as variable form of H. penicillatus. This result implies that
                    the diagnostic key characteristics used by the original description of H. takanoi should be revised
                    accordingly.




                                                                            82




General (poster).indd 82                                                                                                                      09.8.11 9:10:43 AM
                  General Contributed Papers (posters)

                  [GP-59] Molecular phylogenetics of natural populations of the Japanese freshwater
                         crab, Geothelphusa dehaani (Brachyura: Potamidae)
                           Ryoko D. Segawa, Tadashi Aotsuka
                             Department of Biological Sciences, Graduate School of Science and Engineering, Tokyo Metropolitan
                             University, Japan

                  The islands of Japan form a ~3000 km arc along the eastern edge of the Eurasian continent. Genetic
                  variations within species broadly distributed in Japan have been reported. Such variation is thought to
                  be due to microevolutionary factors brought about by past geological and environmental changes in
                  the Japan island chain. The freshwater crab, Geothelphusa dehaani, is a good candidate to examine
                  the impact of geological isolation and environmental changes on genetic divergence. It is endemic to
                  and has a broad distribution in Japan: from northern Honshu to the Tokara Islands, south of Kyushu.
                  In some localities, this species has body color variations. Freshwater crabs hatch directly into crab-
                  like form, with no marine, planktonic larval stages. Thus, these life history characteristics indicate
                  that this species has low dispersal ability. Hence, a relatively high genetic differentiation influenced
                  by geographical isolation may be expected among populations. In this study, we examined molecular
                  phylogenetic relationships among natural populations of G. dehaani throughout their distribution range
                  in Japan. We analyzed sequences of mitochondrial ND2 gene and nuclear ITS (Internal Transcribed
                  Spacer) regions and reconstructed the respective phylogenies for each. Representatives of three closely
                  related species (G. exigua from southern edge of Kyushu, G. marmorata from Yakushima Island,
                  G. sakamotoana from Tokara, Amami and Okinawa islands) were also analyzed. G. minei and G.
                  marginata from Yaeyama islands were used as outgroup taxa. Each of the resulting phylogenetic trees
                  indicates that G. dehaani is not monophyletic, though the overall topologies differ. ITS haplotypes
                  exhibit geographical differentiation, while ND2 haplotypes do not. These topological discrepancies are
                  likely due to inheritance pattern differences between mitochondrial and nuclear DNA. Based on these
                  findings, the historical geological and environmental changes that may have shaped these phylogenies
                  are discussed.


                  [GP-60] Application of proteomics in comparative biochemical studies on crustacean
                         research
                           Masamichi Oh-Ishi
                             Kitasato University, School of Science, Japan

                  Proteome is defined as a complete set of proteins expressed in a tissue or a cell. The purpose of the
                  study is to examine the differences in proteome between various organs and tissues in a decapod
                  species, and to examine the differences in proteome between the species. In order to collect proteomic
                  data, protein constituents of skeletal, cardiac and visceral muscles, and exoskeleton cuticles from
                  various species were extensively examined by two-dimensional gel electrophoresis (2-DE). Similarity
                  values were determined according to Aquadro and Avise (1981). Large values of similarity of 0.75
                  -0.95 was obtained for a leg and claw muscle comparison in a species. In contrast to the muscles,
                  exoskeleton cuticle proteome from dorsobranchial carapace was quite different from that from leg
                  exoskeleton (similarity value: 0.40-0.53) even in a species. When a proteomic comparison among 12
                  species in Grapsidae crabs was made using claw and leg muscle, similarity values of two Chiromantes
                  species were 0.75-0.79, whereas those of two species between Sesarma and Eriocheir subfamilies
                  were 0.64-0.71. These results would provide basic data for phylogenetic and evolutionary studies on
                  crustacean research.




                                                                             83




General (poster).indd 83                                                                                                         09.8.11 9:10:43 AM
                    General Contributed Papers (posters)

                    [GP-61] Host specialization by an octocoral-associated amphipod: process specific to
                           marine systems
                            Naoki H. Kumagai
                               Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan

                    Small marine invertebrates often use sessile organisms as microhabitat (host), which can provide a
                    food source and/or serve as a refuge from predators. Because of the availability of external food items
                    such as epibionts and detritus in the marine environment, these invertebrates may not depend on the
                    hosts as a sole food source. In this study, I hypothesize that host specialization by a marine invertebrate
                    is determined by factors other than food. Results of field surveys off the coast of the Izu Peninsula,
                    on the eastern coast of Japan, showed that, with few exceptions, the distribution of the amphipod
                    Incisocalliope symbioticus was restricted to the octocoral Melithaea flabellifera. When presented with
                    several host options, I. symbioticus selected M. flabellifera most frequently, although some individuals
                    chose the octocoral Acabaria japonica. The selection was proximately determined by water-borne
                    cues from M. flabellifera that appear to be unrelated to the octocoral as a food source, since the
                    amphipod preferred detritus to the octocoral. As a chemical refuge, M. flabellifera had an allelopathic
                    effect that deterred fish predation on the exposed epifauna. With regard to octocoral host in the study
                    area, I. symbioticus may be restricted to M. flabellifera because this was the only abundant octocoral
                    consistently occurring in shallow water ( ≤10 m), where predation is intensive. The relationship
                    between I. symbioticus and M. flabellifera was commensal and was ultimately driven by the value of M.
                    flabellifera as a chemical refuge from predation, rather than its food value. This study highlights the
                    fact that ecological specialization for the purpose of protection from predators can take priority over
                    specialization for food resource utilization in marine systems.




                    [GP-62] Post-marsupial development of Hyalella pleoacuta González, Bond-Buck-
                          up & Araujo, 2006 (Amphipoda, Dogielinotidae) II: stages 5-7 and sexual
                           differentiation
                            Deise Leda Garcia-Schroeder, Paula Beatriz Araujo
                               Laboratório de Carcinologia, Departameno de Zoologia, Instituto de Biociências, Universidade Federal do Rio
                               Grande do Sul, Brasil

                    The goal of the present study is to compare and describe the stages (E) 5 to 7 of the post-embryonic
                    development of Hyalella pleoacuta González, Bond-Buckup & Araujo, 2006 emphasizing sexual
                    dimorphism related to gnathopods and genital papilla in males and oostegites and pores in females.
                    Animals were collected in Vale das Trutas, near São José dos Ausentes, RS, Brazil. Ovigerous females
                    were kept in culture and juveniles were kept individually and monitored for exuvium. Juveniles were
                    dissected and their appendages were mounted in slides and illustrated. SEM was made for detailing
                    of the cuticular structures. There was great variation on the number of articles in the flagellum of the
                    antennae and was higher throughout development. Tendency to increasing in size of the coxal plate in
                    relation to the propod of the gnathopod was noticed in stages 5-7. Sexual dimorphism starts to appear
                    at E5 when the genital papilla in the male and the oostegites in the females start to show. The propodus
                    of the male’s gnathopod 2 gets larger in stage 5 and progressively larger throughout development. The
                    number of setae in gnathopod 2 of the males is slightly higher that the female’s from stage 5 on, and it
                    is enhanced in stage 7. Male’s genital papilla and female’s genital pore do not present ornamentations.
                    The absence of setae in the oostegites in stages 5-7 suggests that despite sexual differentiation is
                    evident, females have not yet reached sexual maturity. Twenty nine types of cuticular structures were
                    found and are present since stage 1 from post-embryonic development. A seta in the male’s uropod
                    in stage 7 was also found and it might develop into a curve seta which is a diagnostic character of the
                    species.



                                                                             84




General (poster).indd 84                                                                                                                     09.8.11 9:10:43 AM
                  General Contributed Papers (posters)

                  [GP-63] DNA barcodes for identification of algae-living gammaridean amphipods (Crus-
                         tacea) from Korea
                           Myung Hwa Shin, Ji Sun Hong, Won Kim
                             School of Biological Science, Seoul National University, Korea

                  Herbivorous amphipods are considered as ecologically important members of marine community in
                  that they role as both consumers and preys in marine food web. Despite their ecological importance,
                  the identification of many algae-living amphipods through morphology is difficult since the juveniles
                  of amphipods hatch as miniature replicas of the adults. Members of two families we tested in this
                  study have their important taxonomic traits on their second gnathopod. To date, two families have been
                  described based mainly on males with sexual dimorphism of second ganthopod and mature females.
                  Thus, immature individuals cannot be correctly identified by their morphological trait. Phenotypic
                  variation of second gnathopod depending on their life stages can lead to misidentification of specimens.
                  We used a short sequence of mitochondrial gene, cytochrome c oxidase 1 (COI), to test the ability of
                  COI identifying algae-living gammaridean amphipods from Korea. We sequenced a 600-base-pair
                  fragment of the COI gene from 13 species belonging to family Ampithoidae and Hyalidae. COI DNA
                  barcodes correctly identified all test specimens of common algae-living amphipods from Korea and
                  we created a reference sequence profile. DNA barcodes offer a promising supplemental tool for the
                  identification of algae-living gammaridean amphipods.




                  [GP-64] Spatial patterns of surf zone crustaceans, Haustrioides japonicus (Amphipoda)
                         and Excirolana chiltoni (Isopoda), on micro-tidal sandy shores at Niigata, Japan
                           Yoshitake Takada, Naoto Kajihara
                             Japan Sea National Fisheries Research Institute, Japan

                  Swash zone of sandy shore, with constant movement of water and sandy sediment, is one of the
                  most physically rigorous habitats for organisms. Nevertheless, several species of animals show
                  morphological, physiological, and behavioral adaptations to colonize into this habitat. Haustrioides
                  japonicus and Excirolana chiltoni are dominant sand-burrowing arthropods at the Niigata area of
                  the Japan Sea coast, where harsh winter storms suppress the density of these species on the shore. In
                  summer, the weather is calm and the density increased at maximum: more than 1x105 m-2 individuals
                  of H. japonicus occur on some shores. In this study, spatial distribution patterns of H. japonicus and
                  E. chiltoni along the Niigata area (60 km) were examined in summer. Twelve shores were selected for
                  the present survey, which were separated by ports, jetties, embankments, and river mouths. Population
                  of these sand-burrowing arthropods are thought to be independent from each other, because the mean
                  tidal range at Niigata area is less than 30 cm and tidal currents do not contribute much for the dispersal
                  of these species between the shores. Density of H. japonicus and E. chiltoni varied between the shores.
                  Sediment grain size alone did not explain the density variation, because fine and medium sand (0.125 -
                  0.5 mm) were dominated at all the shore. Hardness of the sediment partly explained low density of H.
                  japonicus at several shores. Anthropogenic and other effects on the density variation are discussed.




                                                                            85




General (poster).indd 85                                                                                                       09.8.11 9:10:43 AM
                    General Contributed Papers (posters)

                    [GP-65] Benthic sampling effectiveness: a comparative study using the airlift suction
                           sampler and the Ponar Grab for collecting shallow water gammaridean
                           amphipods
                            Azman Abdul Rahim, Ramlan Omar, Wan-Lotfi Wan-Muda, Zaidi Che-Cob, Othman Ross
                               Marine Ecosystem Research Centre (EKOMAR), Faculty Science & Technology, UKM

                    As the broad-scale use of biological monitoring and assessment increases in both the regulatory and
                    research communities, the need for accurate and precise methods becomes more important. Obtaining
                    quality data for a particular study depends largely on the effectiveness of a method during sampling.
                    In this study, we compared the sampling efficiency of two methods; the Ponar grab and the airlift
                    suction sampler. Sampling was conducted with both methods at nine selected stations; each with three
                    replicates along the shallow waters of Pulau Tinggi in Johor, Malaysia. In order for both methods
                    to be standardized, the airlift suction sampler which is usually operated by two divers was used in
                    conjunction with a Perspex quadrat constructed to allow sampling within an area of 0.15m x 0.15m and
                    to a depth of 5cm; which was the exact area and depth of a Ponar grab sampler. Results in determining
                    the efficiency of the ponar grab and the airlift suction sampler were based on the abundance and
                    diversity of benthic gammaridean amphipods collected. The two way ANOVA test and t-test showed
                    significant difference between both methods (P < 0.05) for overall amphipods sampled. Abundance of
                    amphipods collected was higher in airlift samples than grab samples in seven out of the nine stations.
                    Species richness of gammaridean amphipods for airlift samples was also generally higher compared
                    with the grab samples (7-14 species each station). This study has clearly shown the effectiveness of
                    an airlift suction sampler in collecting gammaridean amphipods as opposed to the more conventional
                    method of the using Ponar grab.




                    [GP-66] Three undescribed species of Pseudocrangonyx (Amphipoda: Pseudocrangonyc-
                           tidae) from Japan
                            Ko Tomikawa1), Hiroshi Morino2), Mark J. Grygier3)
                               1)
                                Graduate School of Education, Hiroshima University, Japan; 2) Faculty of Science, Ibaraki University, Japan; 3)
                               Lake Biwa Museum, Japan

                    The freshwater amphipod genus Pseudocrangonyx is known from Japan, the Korean Peninsula, eastern
                    China, and the Far East of Russia. To date, 14 species have been recognized, occurring in spring and
                    groundwater habitats. In Japan, five species have been recorded: P. asiaticus Uédo, 1934; P. coreanus
                    Uédo, 1966; P. kyotonis Akatsuka and Komai, 1922; P. shikokunis Akatsuka and Komai, 1922; and
                    P. yezonis Akatsuka and Komai, 1922. Recently, we found three undescribed species in samples of
                    Pseudocrangonyx collected from various areas of Japan. Four males and 12 females of Pseudocrangonyx
                    sp. 1 were collected from Sekiya Cave, Iwate Prefecture. This species differs from its congeners in a
                    combination of completely absence of eyes, pereonites lacking dorsal setae, posterodistal corner of
                    merus of gnathopod 1 with serrate robust setae, posterodistal corner of carpus of gnathopod 2 with
                    serrate robust setae, and peduncles of pleopods lacking marginal setae. Four females and one juvenile
                    of Pseudocrangonyx sp. 2 were collected from the bed of the Yasu River, Shiga Prefecture. This
                    species is similar to P. kyotonis, but is distinguished by the following features (features of P. kyotonis
                    in parentheses): pereonites 4–6 lacking dorsal setae (present), female antenna 2 with calceoli (lacking),
                    gnathopod 1 without serrate robust setae on posterodistal corner of carpus (present), peduncles of
                    pleopods without marginal setae (present), and distal margin of telson entire (concave). One male and
                    four females of Pseudocrangonyx sp. 3 were collected from Komakado Cave, Shizuoka Prefecture.
                    This species is similar to Pseudocrangonyx sp. 2 but differs from the latter in displaying the following
                    features (features of Pseudocrangonyx sp. 2 in parentheses): gnathopod 2 without serrate robust setae
                    on posterodistal corner of carpus (present), peduncle of uropod 1 with 1 basofacial seta (2 setae), and
                    distal margin of telson concave (entire).




                                                                              86




General (poster).indd 86                                                                                                                          09.8.11 9:10:44 AM
                  General Contributed Papers (posters)

                  [GP-67] Sperm-storage and fertilization in the female of the terrestrial isopod Armadil-
                         lidium vulgare (Crustacea, Isopoda)
                           Sachiko Suzuki1), Andreas Ziegler2)
                             1)                                                             2)
                              Isopod Laboratory, Takamori 83-1, Isehara, Kanagawa, Japan;        Central Facility for Electron Microscopy,
                             Ulm University, Germany

                  Sperm storage was investigated in females of Armadillidium vulgare, employing transmission-
                  electron and light microscopy. Females that bear maturing ovaries receive numerous spermatozoa
                  through the gonopores, causing the oviducts to swell. A space for sperm-storage is formed between the
                  genitalia and the outer epithelium of the oviduct during insemination. Only a part of the spermatozoa
                  are transferred into the seminal receptacle that lies between the oviduct and the ovary. In the seminal
                  receptacle the spermatozoa form a ring shaped structure. At one side the ring is hold in place by cells
                  of the seminal receptacle that surround the bundle of spermatozoa. At oviposition, mature oocytes pass
                  from the ovary through the ring of spermatozoa in the seminal receptacle into the oviduct, and from
                  there through the oopore into the marsupium. During oviposition almost all spermatozoa that lie in the
                  oviduct are lost into the marsupium. However, most spermatozoa within the seminal receptacle are
                  retained during oviposition, although the ring shape of the sperm-bundle becomes disrupted, probably
                  during oocyte-passage. After oviposition the sperm-bundle within the seminal receptacle and possibly
                  spermatozoa left behind within the oviduct reform the ring-structure within the seminal receptacle. The
                  results indicate that after copulation spermatozoa are stored in two storage sites, a newly formed space
                  inside of the oviduct and the seminal receptacle. Storage of spermatozoa in a ring shaped structure that
                  is held just at one side explains how females can fertilize successive broods after a single copulation.




                  [GP-68] Phylogenetic position of the genus Arctotanais Sieg, 1980 (Peracarida: Tanaida-
                         cea: Tanaidae) and the significance of the ischium as the familial diagnosis
                           Keiichi Kakui1), Norio Kobayashi2), Shunsuke F. Mawatari1)
                             1)                                                                      2)
                               Department of Natural History Sciences, Hokkaido University, Japan;        The Hokkaido University Museum,
                             Japan

                  Nine individuals of tanaidaceans were collected at two localities in Hokkaido, Japan. Of these, two
                  specimens were dissected and observed under a microscope for species idintification; from one of the
                  rest of the individuals, DNA was extracted for molecular phylogenetic analysis. The specimens were
                  identified as Arctotanais alascensis (Richardson, 1899) (Tanaidomorpha: Tanaidae). Our observation
                  revealed that ischia are present in all pereopods, contrary to the previously recognized diagnosis for the
                  family. A maximum parsimony analysis based on partial 28S rDNA sequences (815 bp after alignment)
                  from representatives of all tanaid genera available in Japanese waters, i.e., Sinelobus Sieg, 1980,
                  Tanais Latreille, 1831, Zeuxo Templeton, 1840, as well as Arctotanais Sieg, 1980, yielded a single
                  most-parsimonious reconstruction, which is topologically the same as a neighbor-joining tree. Among
                  the four tanaid genera, Arctotanais appeared as the sister taxon to the rest of the family. Transformation
                  of some characters among Tanaidae is discussed.




                                                                         87




General (poster).indd 87                                                                                                                     09.8.11 9:10:44 AM
                    General Contributed Papers (posters)

                    [GP-69] Freshwater species of the genus Gnorimosphaeroma (Isopoda: Sphaeromatidae)
                           in Japan
                            Noboru Nunomura
                               Toyama Science Museum, Japan

                    Hitherto eight species of the genus Gnorimosphaeroma have been recorded from freshwater
                    environments of various parts in Japan. I assumed that the genus is originally a marine dweller, with
                    some species penetrating into brackish or freshwater environments, and therefore, certain primitive
                    features are conserved in marine species. Considering in relation to the pylogeny of the genus, some
                    general tendencies can be recognizable as “advanced characters” such as simplification of body color
                    and reduction in number of antennal segments and setae on appendages. I classified them into at least
                    two main groups (Nunomura, 2004). First group contains four species: naktongense, hokurikuense,
                    rebunense and tsushimaense. They are distributed exclusively in the Sea of Japan side, and they
                    often occur in large population. I consider that they are the relict species of glacial age. Second group
                    contains two species: iriei, disturbed in Kumamoto, west Kyushu and akanense, disturbed in limited
                    places on Pacific side of Hokkaido, I consider that they are relic species of post-glacial transgression,
                    though the latter leaves the possibility to have been imported from the other area in recent years.
                    Recently, I described two new freshwater species: izuense from a small stream of Izu Peninsula,
                    Pacific side of Honshu and boninense from Bonin Islands, respectively. But the both species are not
                    suitable for the above-mentioned two categories. They are apparently most closely to marine species,
                    such as hoestlandti or its allies. I consider that they evolved from them independently and may have
                    adapted to freshwater environment in a relatively short time. Among them, boninense is especially
                    interested in occurring in the oceanic island. But their habitat environment became in danger and was
                    designated as an endangered species in 2006.



                    [GP-70] Two undescribed species of the family Dajidae (Isopoda: Cymothoida) from
                           Japan
                            Michitaka Shimomura1), Susumu Ohtsuka2)
                               1)                                                                2)
                                Kitakyushu Museum of Natural History and Human History, Japan;        Takehara Marine Science Station,
                               Hiroshima University, Japan

                    The Dajidae, a family of the suborder Cymothoida, consists of about 50 species belonging to 19
                    genera, all of which are exclusively ectoparasites of mysid, euphausiid and decapod crustaceans. Four
                    dajid species have so far been recorded from Japan: Prodajus bilobatus Shiino, 1943 from Mysidacea,
                    P. curviabdominalis Shimomura, Ohtsuka and Naito, 2005 from Mysidacea, Holophyryxus fusiformis
                    Shiino, 1937 from sergestid shrimp and Heterophryxus appendiculatus G. O. Sars, 1885 from
                    Euphausiacea. Our parasitological surveys of planktonic invertebrates in Japanese waters have yielded
                    two undescribed species of Notophryxus and Aspidophryxus as the first occurrence of both genera
                    from Japan. Notophryxus sp. was obtained from ventral surface of the pleon of Rhopalophthalmus
                    orientalis O. S. Tattersall, 1957. The present species is most closely related to the Indian congener
                    N. lobatus Pillai, 1963 in having well-developed lateral plates on pleonites in female and distinctly
                    segmented pleonites in male, but clearly differs from the latter by the morphology of the pereon in the
                    female and of the pereonites in the male. Aspidophryxus sp. infected the upper surface of the thorax
                    of an unidentified mysid host, and can be distinguished from its congeners in bearing a pair of well-
                    developed lateral lobes on pleotelson in the female and a pleon lacking uropods in the male. The
                    feeding of these dajids is also discussed.




                                                                       88




General (poster).indd 88                                                                                                                 09.8.11 9:10:44 AM
                  General Contributed Papers (posters)

                  [GP-71] Asellote isopod (Crustacea: Isopoda) from soil habitats
                           Aska Yamaki1), Michitaka Shimomura2), Haruki Karube3), Tomohiko Kikuchi1)
                             1)
                                  Yokohama National University, Japan; 2) Kitakyushu Museum of Natural History & Human History, Japan;
                             3)
                                  Kanagawa Prefectural Museum of Natural History, Japan

                  The Asellidae is one of the largest family in the suborder Asellota, consisting of about 400 species
                  belonging to 20 genera, all of which are benthic dwellers known worldwide from both aquatic epigean
                  and hypogean habitats. Among them, 22 species of four genera have been so far recorded from
                  Japan. A terrestrial faunal survey in Minami-Ioutou Island in Ogasawara (Bonin) Islands conducted
                  by the Tokyo Metropolitan University and Tokyo Metropolitan Govrenment in 2007, have revealed
                  6 specimens of the family. These specimens have collected from forest floor and suspended soils,
                  and recognized to belong to the genus Asellus by the shapes of mouthparts, pereopods and pleopods.
                  Asellote isopods were known only aquatic environment, however the habitat of this study is clearly
                  separated from the water. Morphological characteristics and systematic relationship of these specimens
                  will be discussed with described aquatic species.




                  [GP-72] Population genetics of deep-sea isopod Bathynomus doederleini and cryptic spe-
                         cies revealed by mitochondrial DNA sequences
                           Min-Yun Liu, Hong Young Yan
                             Biological Oceanography Division, Taiwan Ocean Research Institute, National Applied Research Laboratories,
                             Taiwan

                  Bathynomus (Isopoda, Flabellfera, Cirollanidae) is a dominant scavenging isopod genus. As isopod
                  has brooding structure, fertilized eggs develop in the marsupium (brood punch) to juvenile before
                  leaving the maternal body. Isopod is apparently lacking larval dispersal stages, and is expected to show
                  a higher geographic variation in comparison with those with a pelagic stage. Bathynomus dorderleini
                  Ortmann, 1894 is widely distributed in south-western, northern-eastern and east coast of Taiwan.
                  The aim of this study is to estimate the genetic variations of this deep-sea species in Taiwan. Sixty
                  individuals of B. doederleini were collected from two coastal sampling sites, south-western and north-
                  eastern Taiwan. Molecular phylogeny of this species was reconstructed based on two mitochondrial
                  genes, large subunit (16S) ribosomal (r) RNA and cytochrome oxidase subunit I (COI). The Maximum
                  Parsimony (MP) tree showed three distinct groups with high bootstrap support, among which two
                  groups comprised specimen collected from both sampling sites. Estimated genetic divergence among
                  these three groups ranged from 0.8%~1.9% and 3.4%~4.6 % for 16S and COI, respectively. Intra-
                  group genetic divergence ranged from 0.0%~0.4% and 0.8%~1.9% for 16S and COI, respectively. The
                  two groups, which comprised specimen collected from both sampling sites, have low inter-population
                  genetic variation. This phenomenon implies that frequent gene flow is observed in B. doederleini, a
                  brooding crustacean without larval dispersal stages, between populations of south-western and north-
                  eastern Taiwan. The significant genetic differentiation among groups may imply the presence of
                  cryptic species. However, due to the lack of diagnostic characters for species of Bathynomus, revision
                  on the taxonomy of this crustacean group is difficult to accomplish. This species complex must require
                  a more targeted morphological analysis to ascertain its precise taxonomic status.




                                                                           89




General (poster).indd 89                                                                                                                  09.8.11 9:10:44 AM
                    General Contributed Papers (posters)

                    [GP-73] Parasitic prevalence of bopyrid isopods on Metapenaeopsis prawns in the Seto
                           Inland Sea of Japan
                            Hiroshi Kume1), Gyo Itani2)
                              1)
                                   Ehime Fisheries Research Center, Japan; 2) Faculty of Education, Kochi University, Japan

                    Penaeid prawns are popularly consumed crustaceans worldwide. Although bopyrid parasites have
                    negative effect on the growth and reproduction of the hosts, little is known on the ecology of the
                    bopyrid isopods infesting penaeid prawns in Japan. We have studied the prevalence and host specificity
                    of the bopyrids on two species of the penaeids, Metapenaeopsis barbata and M. acclivis, in the western
                    part of Hiuchi-Nada, the Seto Inland Sea of Japan (33º59’N, 133º05’E). Specimens of the prawns
                    were collected monthly from December 2007 to March 2008 and December 2008 to March 2009 by
                    trawling, and the specimens parasitized by the bopyrids were fixed and preserved in ethanol. In winter
                    2007-2008, 6921 specimens of M. barbata and 2799 specimens of M. acclivis were collected, whereas
                    in winter 2008-2009, 3101 M. barbata and 1739 M. acclivis were collected. Both shrimp species were
                    parasitized by Parapenaeon japonica in the branchial chamber. Parasitic prevalence was significantly
                    higher on M. acclivis in winter 2007-2008 (0.3% on M. barbata and 4.1% on M. acclivis) and in winter
                    2008-2009 (0.7% on M. barbata and 4.5% on M. acclivis). Prevalence of bopyrids on the bycatch
                    prawn Trachysalambria curvirostris was much lower. Bopyrid isopods may have severe adverse
                    effects on M. acclivis populations in the Seto Inland Sea.




                    [GP-74] The Lampropidae (Crustacea: Cumacea)
                            Sarah Gerken
                              Biological Sciences, University of Alaska, USA

                    Lampropid cumaceans are characterized by having 3 or more terminal setae on the telson and 0-3
                    pairs of pleopods in the male. At present, about 100 lampropid species are described, but an additional
                    28 provisional species and 5 provisional genera are described, in addition to an overview of the
                    systematics and biogeography of the family. Among the new genera and species described are 3
                    species in the provisional genus, Lampropenis, in which the adult males bear a pair of penial lobes.
                    One of the new species also has a novel ventral structure in the adult male.




                                                                                90




General (poster).indd 90                                                                                                      09.8.11 9:10:45 AM
                  General Contributed Papers (posters)

                  [GP-75] Seasonal occurrence and distribution of Japanese mantis shrimp larvae, Ora-
                         tosquilla oratoria (De Haan), 1844 off Yeonpyeong-do near Korean coast in the
                         Yellow Sea
                           Wongyu Park1), Chae Woo Ma1), Miyoung Song2), Myoung-Ho Sohn2), Hakjin Hwang2), Jong-
                           Bin Kim2), Kwangho Choi2), In-Ja Yeon2)
                             1)                                                                        2)
                               Dept. of Marine BioTechnology Soonchunhyang University, Korea;               West Sea Fisheries Research Institute,
                             Incheon, Korea

                  Seasonal changes and distribution of Japanese mantis shrimp larvae, Oratosquilla oratoria (De
                  Haan), 1844 were investigated off Yeonpyeong-Do near Korean coast in the Yellow Sea. O. ortoria
                  larvae were monthly collected at 15 stations from June to October in 2007. Bongo net with 303 mesh
                  was deployed once with a double oblique tow. No larvae were discovered in June. Zoea I and II
                  were not captured during the entire sampling period. Zoea III occurred in July for the first time and
                  was found until September. Thereafter the proportion of later stages increased. The number of zoeal
                  stages deceased during the summer months and no larvae were found in October. Of zoeal stages,
                  zoea IV was most abundant in number. Zoeal abundance was highest in July and August, particularly
                  at the stations near the coast. O. oratoria larvae may be begun to be produced by the phytoplankton
                  blooming. O. oratoria larvae may be retained and grow within our study sites without advection to
                  growing areas. Non-occurrence of zoea I and II are coincided with previous studies what has been
                  reported from other distribution ranges of the species.




                  [GP-76] Eugregarine infection within the digestive tract of larval Antarctic krill, Eu-
                         phausia superba
                           Kunio T. Takahashi1), So Kawaguchi2), Masaki Kobayashi1), Tatsuki Toda3), Atsushi Tanimura4),
                           Mitsuo Fukuchi1), Tsuneo Odate1)
                             1)                                               2)                                                3)
                               National Institute of Polar Research, Japan;        Australian Government Antarctic Division;         Soka University,
                             Japan; 4) Mie University, Japan

                   Antarctic krill, Euphausia superba Dana (hereafter krill), comprises a significant proportion of the
                  biomass in the Southern Ocean and is an important food source for numerous species of whales, fish,
                  seals, and birds. The eugregarinid protozoan Cephaloidophora pacifica Avdeev (Phylum Apicomplexa,
                  Class Sporozoa) was found from krill digestive tract and the mid-gut gland (hepatopancreas). Heavy
                  infestations of eugregarines in the mid-gut gland are pathogenic and significantly compromise host
                  nutrition. Therefore, eugregarine parasites have the potential to physiologically harm the host causing
                  reduced growth and possibly death. Although there are no studies to date of the larval stages of
                  gregarine hosts, the early life stages are clearly important since their survival rates ultimately determine
                  the size of krill populations. The infection rate of eugregarine parasites within the digestive tract of
                  larval Antarctic krill was examined using samples collected from the Indian sector of the Southern
                  Ocean. Eugregarines were found at all larval stages examined. Eugregarine infection in 14.0% (N=108)
                  the first feeding stage (Calyptopis I) suggested krill larvae are at risk from being infected during
                  physiological transition from non-feeding to feeding stages. Statistical analysis showed the intensity
                  of eugregarine infection increases with host abundance (P<0.05). Thus, krill density is probably a key
                  determinant of the severity of eugregarine infection. We found gamont stage eugregarines in the host
                  hind-gut blocking passage of food across. The parasite also penetrates the intestinal wall. Eugregarine
                  infestations in larval krill would have a negative impact on digestion and absorption in the host
                  digestive tract.




                                                                              91




General (poster).indd 91                                                                                                                                09.8.11 9:10:45 AM
                    General Contributed Papers (posters)

                    [GP-77] Stable isotope ratios of crustaceans in Lakes Shinji and Nakaumi
                            Kengo Kurata1), Masahiro Horinouchi1), David L. Dettman2)
                               1)
                                Research Center for Coastal Lagoon Environments, Shimane University, Japan; 2) Department of Geosciences,
                               University of Arizona, USA

                    Carbon and nitrogen stable isotope ratios have been used to study the relationship between consumers
                    and food materials in aquatic food webs. In coastal brackish water systems carbon isotope ratios of
                    benthic organisms should reflect the potential food sources, such as autochthonous primary producers,
                    phytoplankton and benthic microalgae, as well as allochthonous organic matter derived from coastal
                    or riverine vegetation. Lake Shinji, Lake Nakaumi, and the Ohashi River are the largest brackish water
                    habitat in Japan. The salinity gradient from Lake Shinji to Lake Nakaumi allows us to investigate
                    relationships between environmental gradients and the carbon isotope signatures of crustaceans.
                    Crustaceans were collected at 23 stations in this brackish water system from May to August in 2004
                    and 2005, and carbon and nitrogen stable isotope ratios of the samples were measured. The results
                    showed that most of the carbon stable isotope ratios of crustaceans differed among the water bodies.
                    Carbon stable isotope ratios of the samples from Lake Shinji were lower (–24.2 to –17.7‰) than those
                    from Lake Nakaumi (–14.4 to –10.8‰) with the exception of Sphaeromatidae. Ulva sp., one of the
                    potential food materials for crustaceans, collected from the southern coast of Lake Nakaumi showed
                    unexpectedly high δ13C values (–6.7 to –5.8‰). Crustaceans collected from this area also showed high
                     13
                    δ C values. Carbon isotope ratios of suspended organic matter in the two lakes are different, indicating
                    that carbon stable isotope ratios of crustaceans strongly reflect the ratios of primary producers in
                    nearby water masses in Lakes Shinji and Nakaumi.




                    [GP-78] Molecular phylogeny of Ostracoda
                            Shimpei F. Hiruta1), Shin-ichi Hiruta2), Shunsuke F. Mawatari1)
                               1)                                                                                        2)
                                 Division of Natural History Sciences, Faculty of Science, Hokkaido University, Japan;        Hokkaido Universty
                               of Education, Japan

                    Recent studies on molecular phylogeny of Arthropoda indicated Ostracoda were polyphyletic group
                    (Regier et al. 2008). Although the phylogeny of Ostracoda had been studied on the basis of an
                    abundant fossil record and the morphology of extant species, and also recently through molecular
                    genetic analyses (Yamaguchi and Endo 2003, Yu et al. 2006), the phylogenetic relationships of non-
                    marine ostracods are still unclear (Martens et al. 1998). In the present study, phylogenetic trees were
                    reconstructed by maximum-likelihood (ML), maximum-parsimony (MP), and Bayesian analyses (BA)
                    of nucleotide sequences of the 18S rRNA gene and 28S rRNA gene determined for 18 species in four
                    suborders in Podocopida and one in Myodocopida, and including sequences obtained from GenBank
                    for additional species. The results were as follows. 1) Monophyly was roughly supported for each
                    suborders of Podocopida and Myodocopida in the ML and MP trees, with which it was previously
                    thought to be included. 2) Haleocopida is a paraphyletic group and that Haleocopid ostracods make
                    a cluster with Cephalocarida and Remipedia. 3) Paleocopida make a cluster with Branchiura and
                    Pentastoma. 4) Monophyly of most species (excluding Terrestricythere) in Cytherocopida, one of the
                    major suborders of non-marine ostracods, was highly supported in all analyses. 5) Within Suborder
                    Cypridocopina, each of the superfamilies Cypridoidea, Macrocipridoidea, and Pontocypridoidea was
                    monophyletic, but relationships were not well resolved among the families and genera of Cypridoidea,
                    another major group in non-marine environments. On the basis of phylogenetic trees established, the
                    relationships of each ostracods groups were discussed.




                                                                             92




General (poster).indd 92                                                                                                                           09.8.11 9:10:45 AM
                  General Contributed Papers (posters)

                  [GP-79] Molecular phylogeny of marine interstitial cytheroid Ostracoda
                           Ryouichi Higashi
                             Graduate School of Science and Technology, Shizuoka University, Japan

                  The Ostracoda is one of the major groups of interstitial marine faunas. In the Cytheroidea, more than
                  100 marine interstitial species have been described, belonging to ten families. Four of these families
                  consist of only interstitial species, and their phylogenetic positions were not well understood. To
                  address this problem, their phylogenetic positions were inferred using nucleic 18S rDNA, the first time
                  this has been done for interstitial Ostracoda. The 18S rDNA sequences of 38 species were examined:
                  the data of 11 interstitial species (seven genera in five families) and two surface dwelling species (two
                  genera in two families) were newly obtained for this study; the data for the other 25 species were from
                  the DDBJ/EMBL/GenBank. The phylogenetic analyses were carried out using the neighbor-joining
                  (NJ), the maximum parsimony method (MP), the maximum likelihood method (ML), and the Bayesian
                  analysis. As a result, three clades (Clades A, B and C) were recognized. Clade A, consisting of
                  Bythocytheridae and interstitial Psammocytheridae, was the first to diverge within the cytheroids. This
                  clade forms a sister group with the interstitial Microcytheridae. Clade B, consisting of Loxoconchidae
                  and Cytheromatidae, was the second to diverge. Clade C derived last and consists of a total of 13
                  families including two interstitial families, namely Parvocytheridae and Cobanocytheridae. The
                  phylogeny based on 18S rDNA revealed that the interstitial taxa must have derived frequently within
                  the Cytheroidea, and their adaptive characters (e.g., downsizing, depressed carapace ventro-dorsally or
                  laterally, and lack of an eye) could have developed independently in each taxon.




                  [GP-80] Cloning and expression patterns of the Hox genes in the embryo of the myodo-
                         copid ostracod Vargula hilgendorfii
                           Kyosuke Ikuta, Yoshimi Kohama
                             Department of Biology, Osaka Kyoiku University, Japan

                  Interpretation of the segmentation and tagmosis in the ostracod crustaceans has remained uncertain.
                  Most of the ostracods have only seven pairs of anterior limbs, even including the cephalic ones. The
                  homology of their limbs with those of other crustaceans is open to debate. The posterior “limbless
                  trunk” region has basically no segmental structures and there is no boundary between the thorax and
                  abdomen. Therefore, we regard at least morphologically the ostracods as the most oligo-segmented
                  crustaceans and need to examine their obscure body plan by comparative developmental studies.
                  The Hox genes are required for the specification of segment identities along the antero-posterior axis
                  in arthropods. The expression patterns of the Hox genes have been studied extensively in various
                  arthropod groups to understand the evolution of their body plan. In the present study, we cloned
                  homologs of nine Hox genes, lab, pd, Dfd, Scr, ftz, Antp, Ubx, abd-A, Abd-B and cad from the
                  myodocopid ostracod Vargula hilgendorfii, a famous Japanese bioluminescent species, to observe the
                  embryonic expression patterns of these genes by whole-mount in situ hybridization.




                                                                          93




General (poster).indd 93                                                                                                     09.8.11 9:10:45 AM
                    General Contributed Papers (posters)

                    [GP-81] Mating behavior and reproductive isolation in the species of interstitial genus
                           Parapolycope (Ostracoda: Myodocopa: Cladocopina)
                            Hayato Tanaka, Akira Tsukagoshi
                               Graduate School of Science and Technology, Shizuoka University, Japan

                    The shapes of the male copulatory ducts of eleven interstitial species of the genus Parapolycope were
                    examined and divided into three groups: a helically tube type (Group H), a long tapering tube type
                    (Group L), and a short curved tube type (Group S). Each shape corresponds with the interior structure
                    of the conspecific female genitalia, and therefore gene flow among the groups must be impeded by
                    strong mechanical isolation. The other morphological characteristics of this genus are recognized as
                    sexual dimorphism of the antennula, antenna, and upper lip. Behavioral observations show that the
                    sucker-like accessory on the antennula and the hook-like process on the antenna in the males are used
                    for grasping females during copulation. While clasping the female, the male’s upper lip rhythmically
                    contacts with the lateral side of the female furcal lamella. Furthermore, the male upper lip often
                    exhibits a specific morphology in each species. Reproductive isolation is probably caused by the upper
                    lip behavior of the male. After copulation, the female genital openings are often blocked by circular
                    or rod-shape structures. These structures may function as mating plugs to close the openings of the
                    female genitalia. The rod-shaped structures are part of the male copulatory ducts that have broken off
                    inside the female genital openings. In addition, the phylogenetic relationships of several Parapolycope
                    species are estimated by mitochondrial COI gene sequences. According to this, the extremely long type
                    of copulatory duct must have evolved gradually from the short curved tube type. As a hypothesis to
                    explain the development of the extremely long type of ejaculatory duct, the concept of an “evolutionary
                    arms race” would be applicable.




                    [GP-82] Segmental structures recognized in male copulatory organs of cytheroid
                           Ostracoda
                            Yuriko Nakao, Akira Tsukagoshi
                               Graduate School of Science and Technology, Shizuoka University, Japan

                    The crustacean postantennulary appendages, including the copulatory organs, are assignable to the
                    original “biramous limb”, which have evolved to perform many different functions. The ostracod
                    male copulatory organs are well developed and specialized. A number of studies have added to
                    the terminology and the understanding of the structure and function of each element of the male
                    copulatory organs in some podocopid taxa. However, it is difficult to adapt the terminology established
                    for a certain taxon to other taxa since the male copulatory organs often show extreme morphological
                    complexity and high variety. Furthermore, the extremely specialized male copulatory organ of
                    Cytheroidea has not been compared with the “biramous limb” in view of homology at all. In this study,
                    the male copulatory organs of five cytheroid species (Angulicytherura miii, Callistocythere pumila,
                    Cythere sanrikuensis, Ishizakiella miurensis, and Pontocythere miurensis) were examined. As a result,
                    the segmental structures corresponding to each podomere were recognized, allowing the homology
                    between the male copulatory organs and the “biramous limb”. Furthermore, the derivative parts on
                    the copulatory organs were examined in terms of possible equivalents to independent podomeres,
                    endites, or mere setae on a limb. By comparing the five species, it became clear that the ejaculatory
                    duct (copulatory process) originates from different parts in different taxa. Namely the ejaculatory ducts
                    of these species are not homologous with each other. In view of the relative position of the ejaculatory
                    ducts, three basic frameworks of the male copulatory organ were recognized. This variation in the
                    basic frameworks suggests high plasticity of male copulatory organs in ostracods and the “biramous
                    limb” in crustaceans. The major morphological variation in male copulatory organs, transformed from
                    some basic frameworks, must have caused reproductive isolation and high species diversity in the
                    Cytheroidea.




                                                                            94




General (poster).indd 94                                                                                                        09.8.11 9:10:45 AM
                  General Contributed Papers (posters)

                  [GP-83] The role of the antenna in valve opening in platycopid Ostracoda
                           Yasuhiko Sakumoto1), Akira Tsukagoshi2), David J. Horne3)
                             1)
                              Division of Endocrinology and Metabolism, Jichi Medical University, Japan; 2) Faculty of Science, Shizuoka
                             University, Japan, 3) Department of Geography, Queen Mary, University of London, UK

                  Podocopan ostracods close their bivalved carapaces tightly by means of adductor muscles, but lack
                  either muscles or elastic ligament with which to open them. Valve opening in podocopid (and at least
                  some palaeocopid) ostracods is/was most probably achieved by an outward-directed movement of the
                  mandible coxa, the outer/dorsal side of which is produced to join a pair of chitinous rods (the latter
                  forming a pair of mandibular scars where they attach to the inside of the valve) in a tripod arrangement
                  of which the dorsal top butts against the “fulcral point” on the inner surface of the valve. The existence
                  of a fulcral point or notch, slightly above and in front of the adductor muscles scars, together with
                  more ventrally-positioned mandibular scars, can be regarded as evidence for this type of mechanism
                  even in fossil ostracods without preserved appendages. Platycopid ostracods, on the other hand, such
                  as Keijcyoidea infralittoralis Tsukagoshi, Okada and Horne, 2006, lack such a fulcral point and have
                  relatively weakly developed mandibulae which are not produced to an apex on their outer/dorsal edges.
                  It therefore seems unlikely that platycopids open their valves with the aid of the mandibulae; instead,
                  the antennal precoxa and its musculature may fulfil this role. Accordingly, in platycopids, a small
                  depression in the anterior region of the inner valve surface may be identified as an antennal fulcral
                  point corresponding in function to the mandibular fulcral point of podocopids and palaeocopids. This
                  major difference in valve-opening mechanisms is likely to be related to the different modes of feeding
                  of the major podocopan orders (platyocopids being filter-feeders, most podocopids and palaeocopids
                  being scavengers or carnivores) and different adductor muscle arrangements.




                  [GP-84] Cuticle calcification of the carapace margin in podocopid ostracods
                           Shinnosuke Yamada 1), Dietmar Keyser2)
                             1)                                                                              2)
                              Department of Earth and Planetary Science, The University of Tokyo, Japan;          Zoologisches Institut und
                             Museum, Universität Hamburg, Germany

                  Podocopid ostracods have a calcified carapace encasing their chitinous body like an envelope. The
                  marginal zones along the edges of the carapace are bend over and connect to the flexible inner cuticle.
                  A marginal infold develops along the free margin of both valves notably in the adult stage. Radial
                  pore canals can be seen in the free margin and often exhibit a distinct branched shape with the broad
                  space called “vestibule” in some taxa (e. g., Krithe, Leptocythere). These characters associated with
                  the marginal infold have been recognized as important criteria taxonomically and anatomically, but
                  the calcification process of the marginal infold has never been investigated. This study observed the
                  calcification process of the anterior free margin in Leptocythere species. The free margin of the adult
                  specimen commences its calcification just after ecdysis and keeps its calcification state at the same
                  degree as that of juvenile specimen till about 50h postecdysis. The marginal infold of adult specimen
                  begins then to calcify from its surface part after 50-60h postecdysis and short simple pore canals
                  with broad vestibule can still be observed in the free margin. Marginal pore canals with the line of
                  concrescence are getting more branched and narrower as the calcification proceeds beyond 100h
                  postecdysis. The number and position of pore systems in the anterior margin are quite conservative,
                  though the shape of vestibule shows some variations during the calcification. These results indicate
                  that the calcification of free margin in a podocopid carapace is carried out in two steps and needs much
                  time to complete its calcification even in small Leptocythere. Besides, these observations give a basis
                  for discussion on the correlation on the carapace size, the environmental factors of habitat and the
                  development of vestibule in some Krithe species, so-called the Krithe problem.




                                                                          95




General (poster).indd 95                                                                                                                      09.8.11 9:10:46 AM
                    General Contributed Papers (posters)

                    [GP-85] A new Parathalestris species (Copepoda, Harpacticoida, Thalestridae) from Jeju
                           Is., Korea
                            Sung Joon Song, Ui Wook Hwang
                               Department of Biology, Teachers College, Kyungpook National University, Korea

                    A new species of genus Parathalestris Brady & Robertson, 1873, is herein described as Parathalestris
                    jejuensis sp. nov. from Jeju Is. of Korea. The species is closely similar to Parathalestris infestus Ho
                    and Hong, 1988 which collected from the seaweed farm of Undaria pinnatifida (Miyok=Wakame)
                    of Korea, but can be distinguished from that species by the furcal ramus and its setae, exopod of
                    antenna, setae on proximal endite of maxilla, shape and setal formula of leg 5 in both sexes, etc. The
                    new species is the seventh member of the genus in Korea. Additionally a key to these seven species of
                    the genus was given. This research was supported by a grant from the Ministry of Environment of the
                    Korean Government (NIBR 074-1800-1844-326-260-00) and by the year 2009 grant titled “Origin of
                    biological diversity of Korea: molecular phylogenetic analyses of major Korean taxa” funded by the
                    National Institute of Biological Resources, Korean Government awarded to UWH.




                    [GP-86] Egg development time and hatching success of six dominant copepod species
                           (Copepoda: Calanoida) from the Straits of Malacca
                            Teruaki Yoshida1), Tatsuki Toda2), Ross Bin Haji Othman1)
                               1)
                                 Marine Ecosystem Research Centre, Faculty of Science and Technology, Universiti Kebangsaan Malaysia,
                               Malaysia; 2) Department of Environmental Engineering for Symbiosis, Faculty of Engineering, Soka University,
                               Japan

                    Development time and hatching success is presented for eggs of three congeneric Acartiid copepods
                    copepods, Acartia spinicauda, A. erythraea, A. pacifica and other calanoid copepods Subeucalanus
                    subcrassus, Bestiolina similis and Canthocalanus pauper from the Straits of Malacca (Malaysia).
                    Development time was observed from the time spawned to hatching of eggs to nauplius stage I at six
                    temperatures (10, 14, 18, 22, 27 and 31°C). Development times of the three species were significantly
                    related to incubation temperature and fitted to a Belehradek’s function. Hatching success at
                    temperatures from 14–31oC was on average 61±26, 78±8 and 87±8% for A. erythraea, A. pacifica and A.
                    spinicauda, respectively. S. subcrassus eggs did not hatch at 14oC and the mean hatching success from
                    18–31oC was low at 56±24%. Acartia’s eurythermic hatching success may be characteristic of near-
                    coastal species which experience frequent temperature fluctuations while the smaller range of hatching
                    success in S. subcrassus suggests it is less tolerant to temperature fluctuations. Egg development times
                    of A. erythraea, A. pacifica and A. spinicauda are D = 294 (T–4.47)–2.05, D = 894 (T+1.94)–2.05 and
                    D = 352 (T–4.30)–2.05, respectively. Similar Bělehrádek’s function is suggested to reflect the habitat
                    distribution of A. erythraea and A. spinicauda which primarily inhabit tropical and sub-tropical waters
                    while a lower ‘biological zero’ is reflective of A. pacifica distribution which can extend to temperate
                    regions. The temperature function of S. subcrassus is D=47 (T–13.05)–2.05 and from its high biological
                    zero, it is suggested to be a primarily tropical species. Temperature functions of Bestiolina similis and
                    Canthocalanus pauper are D = 257 (T-3.50)–2.05 and D = 280(T-6.58)–2.05, respectively.




                                                                             96




General (poster).indd 96                                                                                                                      09.8.11 9:10:46 AM
                  General Contributed Papers (posters)

                  [GP-87] Postembyonic development of Metridia pacifica Brodsky, 1950 (Copepoda: Cal-
                         anoida: Metridinidae) from the Japan Sea
                           Kazuyoshi Hashizume1), Kazumasa Hirakawa2)
                             1)                                    2)
                              Kokusai Gakuin High School, Japan;        National Research Institute of Fisheries Science, Fisheries Research
                             Agency, Japan

                  The calanoid copepod Metridia pacifica is very common in the oceanic waters of the Japan Sea.
                  All six copepodid stages (CI to CVI) of M. pacifica were taken in zooplankton samples from 0-500
                  m vertical hauls with NORPAC nets during winter of 1997 in the eastern Japan Sea. The body and
                  appendages at each developmental stage are described and illustrated in detail. The segmentation and
                  setation of mouthparts and 1st-4th swimming legs of the present M. pacifica are compared with those
                  at five copepodid stages (CII to CVI) of Pleuromanma xiphias (Calanoida: Metridinidae) reported by
                  previous study and the external morphological characters of the both species are discussed.




                  [GP-88] Predation impact of the carnivorous copepod Euchaeta concinna (Calanoida:
                         Euchaetidae) on small copepods in the coastal waters of Hong Kong
                           Eva Y.W. Yau, Chong Kim Wong
                             Department of Biology, The Chinese University of Hong Kong, Hong Kong

                  The carnivorous calanoid copepod Euchaeta concinna occurs throughout the year in the coastal seas
                  of eastern Hong Kong. Density >5 ind m-3 appeared in winter and spring and peak density of >8 ind
                  m-3 was recorded in December and January when water temperature was <22°C. The predation impact
                  of E. concinna on small copepods was studied in January 2005 when the density of adult females of
                  E. concinna was 8.3 ind m-3. E. concinna performed diel vertical migration, but the mean depth of the
                  population was below 10 m during both day and night. Feeding occurred at night when the position of
                  E. concinna in the water column overlapped with those of its prey. Analysis of gut contents revealed
                  that small calanoid copepods made up ~40% of the food of E. concinna. Other common prey included
                  unidentified eggs (~29%), remains of unidentified crustaceans (~14%) and other unidentified items (~
                  17%). Acrocalanus gibber made up ~50% of the copepod prey, followed by Paracalanus/Parvocalanus
                  spp. (~30%) and copepodites of Canthocalanus pauper (~11%). Cyclopoid copepods such as Oithona
                  spp., Corycaeus spp. and Oncaea spp. were not found in the gut of E. concinna even though they were
                  common in the water column and were readily eaten by E. concinna in the laboratory. Digestion times,
                  estimated in the laboratory at 18C, varied from 5.3 h for Paracalanus/Parvocalanus to 5.6 h for A.
                  gibber. Predation impact, expressed as the percentage of prey removed daily by E. concinna, was ~ 4.3%
                  for both A. gibber and Paracalanus/Parvocalanus. Because older copepodites of E. concinna can also
                  prey on small calanoid copepods, E. concinna may play an important role in regulating the populations
                  of small copepods in the study area.




                                                                             97




General (poster).indd 97                                                                                                                       09.8.11 9:10:46 AM
                    General Contributed Papers (posters)

                    [GP-89] Population genetic analysis of the calanoid copepods (Crustacea: Maxillopoda)
                           suggests genetic differentiation among geographically isolated populations in
                           marine lakes of Palau
                            Shinichi Saitoh, Hidetoshi B. Tamate
                               Graduate School of Science and Engineering, Yamagata University, Japan

                    Empirical studies on allopatric speciation in marine organisms have been limited because geographical
                    barriers which are often observed in terrestrial organisms are less likely to be formed in marine
                    environment. Therefore, speciation of marine holoplankton is supposed to proceed at a large
                    geographic scale when continental land mass or ocean circulation becomes the barriers. However,
                    little is known about the initial phase of speciation—genetic differentiation among populations—under
                    isolated conditions. To study the process of genetic differentiation in holoplankton as a consequence of
                    geographic isolation, we carried out genetic study on the pelagic copepod population in marine lakes
                    of Palau islands. The marine lakes, which consist of more than 50 lakes in high limestone islands,
                    are located geographically close to each other and connected to the outer open sea at various degrees.
                    We hypothesized that isolated marine lakes accelerate allopatric speciation and natural selection of
                    copepods. We conducted field surveys during 2004-2008 and collected samples from coastal areas and
                    marine lakes. Intra-specific genetic variations in coastal or brackish species of the calanoid copepods
                    were studied by genetic analysis using mitochondrial cytochrome c oxidase subunit I (mtCOI) gene
                    sequence as a DNA marker. The level of genetic diversity within a population was relatively low, while
                    that among populations was high, indicating the restricted gene flow or complete isolation. Statistical
                    parsimony haplotype networks showed that there are no shared haplotypes among the marine lakes
                    and unique mutations occurred in each marine lake. The present study thus provides for the first time
                    the empirical data of genetic differentiation of copepods in isolated environment. However, further
                    investigation using other DNA markers or gene expression analysis would be needed to determine
                    whether natural selection is presence at isolated population.


                    [GP-90] Phylogeny of the ‘Turtle & Whale barnacles’ Superfamily Coronuloidea
                            Ryota Hayashi
                               Chiba University, Japan

                    Barnacles are known to occur on all situation of ocean, from intertidal zone to deep sea. On the other
                    hand, Some species occur on marine vertebrate such as marine turtles, whales, dugongs, manatees,
                    sea snakes and so on. These species were all included Supefamily Coronuloidea (Newman, 1996).
                    After the work, classifications of barnacles were modified by many authors (e. g. Pitombo, 2004) but
                    classification of turtle and whale barnacles were not modified because these species occurs on only
                    marine vertebrates, we can not get these easily. So, there is no cladistic and phylogenetic analysis of
                    superfamily Coronuloidea. In this study, partial sequences of two mithochondrial genes, 12S rDNA
                    and 16S rDNA, and a nuclear gene, 18S rDNA, were used to infer the molecular phylogeny of the
                    Coronuloidea and we attempted to evaluate familial relationships within Coronuloidea, proposing
                    a high-level evolutionary hypothesis among them. These relationships will form the basis for a
                    discussion of character evolution in this group.




                                                                            98




General (poster).indd 98                                                                                                       09.8.11 9:10:46 AM
                  General Contributed Papers (posters)

                  [GP-91] Structure of the outer muscle wall of the alimentary tract of Artemia
                           Masaki Ueno
                             Kitasato University, School of Allied Health Sciences, Japan

                  In this study, the structure of the outer muscle wall of the alimentary tract of Artemia was investigated
                  by scanning electron microscopy. The body length of Artemia nauplius is only approximately 0.4 mm;
                  therefore, it is difficult to dissect its intestines. Whole larvae of Artemia nauplius were fixed, and the
                  dried samples were mounted on an aluminum base with the aid of carbon paste. The alimentary tract
                  was then dissected under a stereoscopic microscope by using the bristle of a plastic toothbrush at the
                  tip of a bamboo skewer. The outer surface of the alimentary tract was observed after thin-film coating
                  with osmium. The intestine was observed to be surrounded by a layer of circular muscle. Each circular
                  muscle appeared flattened and belt-shaped and were arranged separately. The filamentouse attenuate
                  prominence of the muscle surface seems to touch next to each other. Since the nerves distributed over
                  each circular muscle do not innervate the muscle, I considered that neural communication between the
                  circular muscle cells and the nerves are mediated via these filaments. Most of the mid-gut was covered
                  by close circular muscle cells, but a pair of gastric caeca was covered by sparse band-shaped muscle
                  cells. Fixation was carried out as follows: treatment with 7% glutaraldehyde (microwave irradiation of
                  350W for 4 min) for 24h followed by 2% osmium tetroxide for 2h. Dryness: After washing the samples
                  to remove fixative, the samples were dried using a critical point dryer. Coating: The outer surface of
                  the alimentary tract was coated with a 20-nm-thick osmium film by using an osmium plasma coater.




                  [GP-92] Spatial differentiation of three sympatric branchiopods (Crustacea, Bran-
                         chiopoda) in Taiwan
                           Chung-Chieh Wang, Shiang-Lin Huang, Wan-Ping Huang, Lien-Siang Chou
                             Department of Life Science, Institute of Ecology and Evolutionary Biology, Taiwan

                  Originally a volcano-formed crater in Yangmingshan National Park in northern Taiwan, Siangtian Pool
                  has been a habitat for branchiopods of Branchinella kugenumaensis, Eulimnadia sp., and Lynceus
                  biformis for at least 2 decades. This ephemeral pool is formed when the heavy rain brought along
                  by the typhoons fills up the pool. To cope with the unpredictable environment of the pool, the three
                  sympatric branchiopods have developed specific life history strategies. In this study, we explore the
                  pattern of their spatial distribution and its role in niche differentiation of the community. During the
                  period of July to October 2008, three typhoons passed over the area, of which the first typhoon formed
                  water phases P1, and the next two typhoons formed water phase P2 at Siangtian Pool, each lasting
                  6 and 32 days respectively. We used plankton net to collect samples along the concentric circles and
                  isobaths transect lines of the pool with depth category by 30 cm. We found clear differentiation in
                  spatial distribution of the three branchiopods species based on their distribution density. Each species
                  had its own spatial hot spots, but the position of these hot spots changed frequently, both horizontally
                  and vertically. Although Branchinella tended to gather toward the edge regions, none of these three
                  sympatric branchiopods kept dominating at any specific site, and their distribution could change
                  everyday. We will discuss the possible factors that influence on the spatial usage of branchiopods
                  community in Siangtian Pool.




                                                                            99




General (poster).indd 99                                                                                                      09.8.11 9:10:47 AM
                    General Contributed Papers (posters)

                    [GP-93] Screening and expression analysis of genes responding to predator kairomones
                           in the water flea Daphnia pulex
                            Hitoshi Miyakawa, Maki Imai, Toru Miura
                               Graduate School of Environmental Science, Hokkaido University, Japan

                    Among aquatic animals, various cases of the predator-induced polyphenism have been so far
                    reported, in which alternative phenotypes are produced in response to extrinsic stimuli. The genus
                    Daphnia provides a model experimental system for the study of developmental mechanisms and
                    evolutionary processes of predator-induced polyphenisms. In D. pulex, juveniles form neckteeth in
                    response to predatory kairomones, released by Chaoborus larvae. Previous studies suggest that the
                    sensitive periods to kairomone can be roughly divided into two developmental periods, embryonic
                    and postembryonic periods. In this study, therefore, we explored genes exhibiting different expression
                    levels in the presence or absence of predator kairomone during embryonic and/or postembryonic
                    stages. The combination of candidate gene approach and differential display identified **
                    differentially-expressed genes (** up-regulated and ** down-regulated), including novel ones. Among
                    them, morphogenetic factors, Hox3, extradenticle and escargot were up-regulated by kairomone in
                    the postembryonic stage. These might be responsible for the defense morph formation. In addition,
                    juvenile hormone pathway genes, JHAMT and Met, and insulin signaling pathway genes, InR and
                    IRS, were up-regulated in the postembryonic stage. It is well known in many arthropod species that
                    these hormonal pathways are involved in physiological regulations followed by morphogenesis.
                    While, in the embryonic stage, one of novel genes obtained by differential display was up-regulated,
                    suggesting that this might be related to the morphotype determination. Biological functions of the
                    differentially-expressed genes are discussed in the context of defense morph formation. Furthermore,
                    detailed transcript localization analyses on the identified genes by in situ hybridization suggest that
                    they are required for the series of phenotypic transitions from the reception of kairomone signals to the
                    developmental processes of defensive phenotype including both morphology and behavior.


                    [GP-94] A novel type of ‘meiosis’ found in parthenogenetic Daphnia pulex (Crustacea:
                           Cladocera)
                            Chizue Hiruta1), Chizuko Nishida2), Shin Tochinai3)
                               1)
                                 Graduate School of Science, Hokkaido University, Japan; 2) Department of Biological Sciences, Faculty of
                               Science, Hokkaido University, Japan; 3) Department of Natural History Sciences, Faculty of Science, Hokkaido
                               University, Japan

                    Most daphnid species adopt parthenogenesis and sexual reproduction differentially in response to
                    various environmental cues, resulting in the production of diploid progenies in both cases. Previous
                    studies have suggested that daphnids make their parthenogenetic eggs via apomixis, where the embryo
                    arises from an unfertilized egg that was produced by mitosis. In apomictic parthenogenesis, no
                    chromosome reduction takes place during oogenesis, thus maintaining the same set of chromosomes as
                    the mother. It has also been reported that the oocyte emitted at least one polar body during maturation.
                    This means, in turn, that the nuclear division may be an equational one as the somatic mitosis.
                    However, this has not yet been unequivocally demonstrated in any daphnids. Therefore, in the present
                    study, a detailed histological observation has been made in parthenogenetically propagating D. pulex
                    to reveal the behavior of chromosomes during oogenesis and development. The chromosome tracings
                    showed that the nuclear division apparatus appeared soon after the breakdown of germinal vesicle,
                    and each chromosome began separating into two halves. Quite interestingly, however, the division was
                    arrested in the middle of the transition from metaphase to anaphase. Then, each chromosome moved
                    back to equatorial plane, and a complete chromosome separation (equivalent to polar body emission)
                    followed immediately after egg-laying. These results suggest that parthenogenetic eggs enter the first
                    meiosis, but this process culminates in an incomplete division and then the next division corresponding
                    to the second meiosis takes place. From these observations, we hypothesized that an abortive meiosis
                    occurs to maintain diploidy before parthenogenetic development. To validate this hypothesis, it must
                    be determined whether the pairing of homologous chromosomes, which is a feature unique to meiosis,
                    occurs during the first division. We will present the detailed cytological examinations made on the
                    oocytes and developing early embryos to clarify the chromosomal behavior in D. pulex.

                                                                            100




General (poster).indd 100                                                                                                                     09.8.11 9:10:47 AM
                  General Contributed Papers (posters)

                  [GP-95] Toxicity of chlorpyrifos and its bioconcentration in a brine shrimp population
                         Artemia sp. (Crustacea: Branchiopoda: Anostraca)
                            Dola Bhattacharjee, Olivia J Fernando
                                CAS in Marine Biology, Annamalai University, India

                  Organophosphorus pesticides, like chlorpyrifos, are used worldwide in agriculture. These are
                  neurotoxins and non-target specific. Determination of acute toxicity of chlorpyrifos and their
                  bioconcentration at a lower tropic level is a very necessary step towards the its controlled use. Owing
                  to their worldwide application in hatchery raring of fish larvae, different life stages of a local Artemia
                  strain were exposed to various concentrations of chlorpyrifos, for the purpose. 24h-LC50s for Artemia
                  nauplii, juveniles as well as adults for the pesticide were found to be 20, 5.2 and 0.06mg/L respectively.
                  Artemia life stages were found differentially sensitive to the pesticide concentration. Bioconcentration
                  of chlorpyrifos by the post-larvae of Artemia was also investigated and it was observed that at the end
                  Table 1. Acute toxicity of chlorpyrifos for Artemia. Mean, n=5.
                                                                                                                 of 24h of exposure, bioconcentration
                             Life stage of Artemia                                24h-LC values
                                                                                                                 was at higher levels at 100, 10 and
                                      Nauplii
                                                                            50
                                                                                       20.00                     1µg/L of the pesticide. Our findings
                                     Juveniles                                          5.20                     are in agreement with that of earlier
                                      Adults                                            0.06                     authors, however, the explanation by
                                                                                                                 others that ill-developed digestive
                  Table 2. Bioconcentration of chlorpyrifos in Artemia juveniles. Mean, n=5.                     system in the Artemia nauplii as
                   Concentration in water (µg/L)        Time of exposure (h)      Concentration in animal tissue a probable reason for their least
                                                                                              ( µg/g)
                                 100                              24                            5.20             sensitivity towards contaminants,
                                  10                              24                            1.70             was ruled out. It was concluded that
                                   1                              24                            0.11             organophosphate pesticides like
                                   1                              48                            6.00             chlorpyrifos is a threat to the aquatic
                                  0.5                             24                            0.01
                                                                                                                 ecosystem.
                              0.5                       48                       0.48




                    [GP-96] Morphological and genetic variations among local populations of the genus
                           Eriocheir crabs in Japan
                              Izumi Yamasaki1), Seiichi Watanabe2)
                                    1)                                                                                            2)
                                     National Research Institute of Far Seas Fisheries, Fisheries Research Agency, Japan;              Tokyo University of
                                    Marine Science and Technology, Japan

                    There are two species of Eriocheir crabs in Japan. One is the Japanese mitten crab Eriocheir japonica,
                    a common varunid species found throughout freshwater and estuarine regions in Japan. The other one
                    is the Ogasawara mitten crab E. ogasawaraensis distributed only in the Bonin Islands (“Ogasawara
                    Islands” in Japanese) which are oceanic islands far isolated from the Japanese main islands. We have
                    conducted genetic and morphologic analyses on the samples from main islands (Hokkaido, Honshu,
                    Shikoku, and Kyushu) and some isolated islands (Ogasawara Island and Ryukyu Archipelago) and
                    clarified the notable genetic and morphologic differences between them. Specimens were newly
                    collected from two characteristic sampling sites for this study. One of the new sites “Abashiri” is
                    facing the southern part of the Sea of Okhotsk. The other site is “Horawasawa” on the Hachijo Island
                    located between the Ogasawara Islands and Honshu. Morphologic and genetic characters of these
                    samples were compared with the samples which have been used in previous studies. We used only
                    adult males for morphological analysis. Carapace, eyestalk and first gonopod (G1) were measured for
                    width and length, respectively, and the number of granules on the epistomal margin were counted.
                    We found the geographic trends for the shape of G1 and number of granules. The shape of G1 was
                    thicker and shorter on the main islands of Japan and narrower and longer on the isolated islands.
                    Number of granules were more numerous on the isolated islands than the main islands. Additionally,
                    the specimens from Hachijyo lack setae on the ventral surface of the chelae, sharing this feature with
                    E. ogasawaraensis; however, the carapace width was less than that of E. ogasawaraensis. Genetic
                    analysis on mitochondrial 16SrRNA partial sequence for new samples are being conducted now.


                                                                                  101




General (poster).indd 101                                                                                                                                    09.8.11 9:10:47 AM

				
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