The pygmy hippopotamus or pygmy hippo (Choeropsis liberiensis) is a small hippopotamid which is native to the forests and swamps of West Africa, primarily in Liberia, with small populations in Sierra Leone, Guinea, and Ivory Coast. It has been extirpated from Nigeria.
The pygmy hippopotamus is reclusive and nocturnal. It is one of only two extant species in the family Hippopotamidae, the other being its much larger relative, the common hippopotamus (Hippopotamus amphibius) or Nile hippopotamus. The pygmy hippopotamus displays many terrestrial adaptations, but like the common hippopotamus, it is semiaquatic and relies on water to keep its skin moist and its body temperature cool. Behaviors such as mating and giving birth may occur in water or on land. The pygmy hippopotamus is herbivorous, feeding on ferns, broad-leaved plants, grasses, and fruits it finds in the forests.