Family
Tragulidae
Chevrotains |
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Sometimes called "mouse deer" due to their tiny stature, chevrotains
are the smallest extant ungulates, never weighing over 20 kilograms (adults
of the genus Tragulus may weigh less than 1.5 kg). Most members
of the Tragulidae inhabit tropical forests in southeast Asia, but a single
species is found in central and western Africa; all species feed mainly on
grasses and leaves from the forest floor. Physically, chevrotains resemble
other small forest-dwelling herbivorous mammals such as the South American
agouti (Dasyproctidae, Rodentia) and African duikers
(Cephalophinae, Cetartiodactyla), with
forward-sloping shoulders and powerful hind quarters.
The fossil record of chevrotains begins in early Miocene deposits in Europe,
where they persisted until the early Pliocene. Chevrotains spread to
Asia during the Miocene, and the majority of species still inhabit the
southeastern portion of this continent. The Tragulidae are known in
Africa from fossils from the early to middle Miocene, but do not reappear
in the African fossil record until the Pleistocene. There are three
modern genera and eight species. Recent taxonomic revisions of the
Tragulidae have split the two former species of the genus Tragulus
(T. napu and T. javanicus) into six species; as no studies
on the relationships within this revised genus have been performed, the family
tree (below) is still incomplete.
Four digits are present on each foot, but the second and fifth digits are
short and slender. The stomach has four chambers (like the rest of
the ruminants), but the omasum is rudimentary. The skulls of tragulids
are small (condylobasal length is less than 10 cm). In males, the upper
canines form tusks which protrude downwards from the mouth. The lower
canines resemble incisors. The dental formula is I 0/3, C 1/1, P 3/3,
M 3/3 x 2 = 34. There is a unique plate of bone to which the sacral
vertebrae attach. |
The Chevrotain Family
Tree
(branch lengths are not proportional to
time)
Click on the species above to learn
more,
or jump to the Tragulidae Species
List
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Literature Cited
Martin, R. E., R. H. Pine, and A. F. DeBlase. 2001. A Manual
of Mammalogy, Third Edition. Boston: McGraw-Hill Publishing.
Nowak, R. M. [Editor]. 1991. Walker's Mammals of the World. Fifth Edition.
Johns Hopkins University Press, Baltimore.
Vaughan, T. A., J. M. Ryan, and N. J. Czaplewski. 2000. Mammalogy. Fourth
Edition. Saunders College Publishing, Philadelphia.
Wilson, D. E., and D. M. Reeder [editors]. 2005. Mammal Species of
the World (3rd Edition). Johns Hopkins University Press, 2,142 pp.
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