Hippopotamus (Hippopotamus amphibius) - Includes facts, photos and videos of the hippopotamus. Hippopotamus amphibius - Lisa Frisch provides information on this mammal, its classification, habitat, adaptations, nutrition and reproduction. Pygmy Hippopotamus (Hexaprotodon liberiensis) - Fact sheet from EDGE, a conservation organization that focuses specifically on threatened species that represent a significant amount of unique evolutionary history. Pygmy Hippopotamus: Choeropsis liberiensis - Photographs, videos and information from ARKive including classification, status, description, range, habitat, biology, threats and conservation. Hippopotamus: Hippopotamus amphibius - Many videos and photographs with details of classification, status, description, range, habitat, biology, threats and conservation. Hippopotamus (Hippopotamus amphibius) - Factsheet from Arkive with videos and images, physical characteristics, habitat, diet, reproduction, and conservation status.