invert crustacea by liamei12345

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									    Sub-phylum Crustacea

• crabs, lobsters, shrimps, crayfish,
  barnacles, water fleas, fairy shrimps,
  copepods, isopods, & amphipods
Crustacean Diversity
           General Features
•   diversity (30,000 species)
•   fresh water & marine; terrestrial
•   sessile, commensal, & parasitic
•   biramous appendages
•   (2) pair of antennae
•   (1) pair of mandibles
•   (2) pair of maxillae
•   gills (usually)
•   tagmata (e.g. cephalothorax)
         Form & Function:
• appendages: specialization
     • swimmerets, uropods, & chelipeds
• feeding
     • filter feeders, scavengers, parasites, &
       predators
• respiration: diffusion & gills
• excretion/osmoregulation:
     • green gland- excretes ammonia
• circulation: open w/ hemocoel
            Reproduction
• mostly dioecious

• direct or indirect
  development

• planktonic larvae in
  many
          Class Cirripedia
• barnacles

• sessile (adults); marine, filter
  feeders

• respiration via the integument; no
  heart
Barnacles
Class Copapoda “cyclops”
        Class Branchiopoda
• brine shrimp, fairy shrimp,
  and water fleas

• characteristics: small size,
  filter feeders, gilled, &
  locomotory & zooplankton

• Orders: Cladocera,
  Notostraca, & Anostraca

• parthenogenesis

• Daphnia used indicators of
  water quality
Order Notostraca- tadpole shrimps

• nine species; one family

• generally inhabit
  ephemeral lakes (playas)
Order Anostraca- fairy shrimps
• fairy and brine shrimps
  (sea monkeys)


• often inhabit ephemeral
  pools
 Class Ostracoda- seed shrimps
• 6,650 species

• 54 genera and 420
  freshwater spp.

• fresh water, marine, &
  estuarine

• consume mostly algae
  and organic detritus
        Class Malacostraca
• largest and most diverse class

• crabs, shrimps, crayfish, lobsters, isopods,
  etc.

• marine, fresh water, and terrestrial

• benthic; scavengers, predators
      Order Isopoda
• pill bugs, sow bugs, or
  “rolley polly”

• aquatic and terrestrial
  forms

• Dorso-ventrally
  flattened body
           Order Amphipoda
• sand fleas & scuds

• laterally compressed
  body

• marine & fresh water
       Order Decapoda
• largest order- > 10,000
  species; 100 families

• crabs, lobsters, shrimp,
  crayfish, and hermit
  crabs

• marine, fresh water, &
  terrestrial

• chelipeds- grasping
  appendage
Callinectes- blue crab
megalopa
Crayfish Morphology
          Ecdysis (molting)
• the Y-organ in the head
  of crustaceans controls
  ecdysis

								
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