Edentates, Pholidotes, and
An hodge-podge of ant
The edentates (without teeth) include 4
families: armadillos, sloths, and
Verm – worm, lingua – tongue.
All are new world.
Only the 9-banded armadillo gets into the
Have relatively low body temperatures
(34°C) compared to other eutherians.
In spite of this, 9-bandeds have been
extending their range northward.
Old name edentata is inappropriate
because only the anteaters are without
New name, xenarthra, refers to accessory
zygapophyses on the lumbar vertebrae.
These ‘extra’ articulations increase the
rigidity of the axial skeleton.
Incisors and canines are lost.
Molars and premolars lack enamel and are
In anteaters and armadillos, the acromion
and coracoid are unfused and substantial,
aiding powerful digging.
Anterior caudal vertebrae have transverse
processes fused to Ischium.
Aardvark ventral skull:
note lack of incisors.
Aardvark molars: note lack
Group was once much more diverse than
today, with some extinctions occuring
within recorded history.
Glyptodon was huge: 2m total length.
Note what happens to the vertebral
2 species of arboreal 2-toed sloths and
Choloepus hoffmani occurs from Nicaragua
to Peru and Brazil, while C. didactylus occurs
only in S. America, east of the Andes.
Lack incisors and canines.
First upper premolar is caniniform, and
separated from other cheek teeth by a
2-toed sloth utr: note diastema and
caniniform premolar, and articular
3-toed sloth utr
2 and 3 toed sloths. Both have incomplete
zygomatic arches, and the jugal forms a flat
Extinct xenarthrans: Glyptodon
Our extinct ground sloth:
Nothrotheriops: survived in N. America
until about 11,000 years ago.
Right pes of
and the right
2-toed sloths have “SURPRISE” 2 claws on fore-
feet, and 3 on the rear, while 3-toed sloths have
3 claws on the fore-feet.
2-toed sloths hang upside down almost all the
time, except to defecate.
Exclusive arboreal folivores.
Symbiotic algae in the pelage.
Body temp varies from 24-33C.
Number of cervical vert. Varies from 5-8!
Collared anteater claw: corresponds
to ‘D’ on previous slide.
Bradypus tridactylus is distributed from
Honduras to Brazil. B. variegatus?
Less active than 2-toed sloths, using only
a single tree each day.
Segmented stomach w/ microflora. Active
day and night: Arboreal folivory is tough.
8-9 cervical vert: 270 degree rotation.
4 species, with no teeth.
Distributed from S. Mexico to Paraguay.
Giant anteaters tongue is 13mm wide, but
extendable to 600mm! It is anchored to
the base of the sternum, is covered by
submaxillary secretion, and has posteriorly
directed barbs to trap ants.
Collared anteater palate
8 genera and 20 species.
9-banded is only xenarthran in N.
They have extended their range
dramatically since the early 1800’s.
Northern limit is probably defined by
temperature. High thermal conductance,
and an inability to enter torpor.
Excellent diggers … it is almost impossible
to fence them in.
Opportunistic feeders: invertebrates, plant
material, and carion.
Defensive behaviors: roll into a ball or
Vertebrae modified for attachment of
carapace to lumbar vertebrae via
Size varies from ‘pink fairy armadillo’ at
100g to giant armadillo at 60kg.
Open rooter, homodont molariform teeth
Dasypus has delayed implantation.
Monozygotic polyembryony in some.
In Dasypus novemcinctus there are 4
young of same sex, all from a single
They are used as models for medical
models for leprosy research.
Giant and 9-banded armadillos.
9-banded armadillo utr
3 banded armadillo
3 banded armadillo
These are the pangolins.
There are 4 species in sub-saharan Africa,
and 3 species in India, Pakistan, China, Sri
Lanka, southeast Asia, and Indonesia.
They are ant-termite specialists w/
powerful digging abilities – sometimes
semi-arboreal w/ semi-prehensile tails.
Poor vision and hearing, but olfaction is good.
Scent marking – anal scent glands may be used
Response to predation is to roll up in a ball like
many other mammals.
Scales are soft at birth.
African species do not have external ears, but
asian species do.
Truly edentate w/ long, sticky tongue
(salivary gland is large and located in
chest). Tongue is enclosed in a sheath,
passes over the sternum, and is anchored
on the pelvis.
Incomplete zygomatic arch, and slender
dentary (reduced musculature for
Gizzard like pyloric region in stomach for
grinding up ants and termites.
Mid-Eocene pangolin, Oligocene pangolin,
Eomanis, is found in Patriomanis, is found
Europe. in N. America.
Order is monotypic, contains only
Orycteropus afer of Africa.
Ant – termite specialist. Note: there are
lots of ants and termites in Africa, and lots
of lizards specialize on ants and termites
Acute olfaction and auditory senses.
Travel as far as 30km/night.
Aardvark is Afrikaans for ‘earth pig.’
Nostrils are protected from dirt and ants
during digging by hairs.
Extensive turbinate bones – good olfaction.
Reduced eyes – characteristic of
myrmecophagus species, but has erect ears –
Strong clawlike nail for digging out ant/termite
Tubule-teeth: fetal stage has incisors and
canines. Ontogeny recapitulates phylogeny?
Teeth are open-rooted w/o enamel, and
covered w/ cementum.
Ants and termites are ground up in muscular
pyloric region of stomach.
Miocene fossil Myorycteropus is from E. Africa.
Orycteropus gaudryi is Miocene, and
Leptorycteropus is from mid-pliocene.
Pleistocene fossils are from France, Greece,
Turkey, india, and Madagascar.
There will be outhouses.
Make sure your food group is ready:
Make sure you have Bring your field notebook,
enough food and and your skin and stuff
If you want a fire at You will bust your but in
night, make sure you the field, so be prepared.
bring wood, matches, NO BITCHING!
and kindling. Tent and bag?
Bring 1 change of No hunting.
clothes in case it Bring an orange vest/hat.
Water. Nobody cares what
Be prepared for cold you look like in the
wet weather. field – we will all be
Wool is better than ugly together.
down when its wet. If you don’t bring
Dry feet are your rap music, I
important. won’t bring my Miles
A tooth brush will
chase away the No Radios.