Pygmy Hippopotamus

From Wikipedia, the free encyclopedia

iPygmy Hippopotamus

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Family:	Hippopotamidae
Genus:	Choeropsis
Species:	C. liberiensis

Binomial name

Choeropsis liberiensis
(Morton, 1849)

Subspecies

C. l. heslopi
C. l. liberiensis

The Pygmy Hippopotamus (Choeropsis liberiensis) is a large mammal native to the forests and swamps of western Africa (the species name, meaning "of Liberia", reflects this). It is one of only two extant species in the hippopotamus family. Unlike its larger relative, the Hippopotamus, relatively little is known about the Pygmy Hippo's diet or behavior, although it is clear that the Pygmy Hippo is adapted to forest environments rather than the more open plains and grasslands that the Hippopotamus prefers. Some authors place the Pygmy Hippo in the genus Hexaprotodon, along with a number of fossil forms.

Pygmy Hippos stand about 75 cm (30 inches) high at the shoulder and weigh 180 kilograms (400 pounds). They are more solitary than their larger relatives and considerably less aquatic. The skin is greenish-black, shading to a creamy gray on the lower body. The average lifespan is 35 years, and one in captivity reached the age of 42. The gestation period ranges from 190-210 days, and usually a single young is born. Pygmy Hippos live either alone or in small groups, typically a mated pair and one calf.

Skull of a Pygmy Hippopotamus

All species of hippo spend most of their time in the water, emerging mainly at night in order to feed on land. The Pygmy Hippo is half as tall as the Hippopotamus and weighs 1/10 as much as a small member of the larger hippo species. The fossil record suggests that the Pygmy Hippo is closer in form and possibly behavior to the common ancestor.

Pygmy hippos exist in two populations. One ranges in Guinea, Sierra Leone, Liberia and Côte d'Ivoire. The other population, with a different shape to the skull, ranged until recently in the Niger Delta but may now be extinct.

There are two subspecies of the pygmy hippopotamus. Choeropsis liberiensis heslopi is a critically endangered subspecies, and may possibly even be extinct. The other subspecies, Choeropsis liberiensis liberiensis, is a category 4 (vulnerable)

Pygmy Hippo at Bristol Zoo, England

[edit] References

Boisserie, J.R. 2005. The phylogeny and taxonomy of Hippopotamidae (Mammalia: Artiodactyla): a review based on morphology and cladistic analysis. Zoological Journal of the Linnean Society, Volume 143, Number 1, January 2005, pp. 1-26(26)
ITIS data as of 2004-08-11

Pygmy hippo at Toronto Zoo