Hypohippus (Greek: "under" (hypos), "horse" (hippos)[1]) is an extinct genus of three-toed horse, which lived 17–11 million years ago.[2] It was the largest anchitherine equid about the size of a modern domestic horse, at 403–600 kg (888–1,323 lb)[3][4] and 1.8 m (5.9 ft) long. It was a long-necked, high-shouldered browser with sub-hypsodont, lophodont (rhino-like) dentition, that fed on the tough vegetation of forest understory and shrubs. Its deep preorbital fossae and retraction of the nasal notch hint at the presence of a long, muscular and prehensile upper lip that would aid during selective browsing. Overall its ecology would have been more comparable to modern okapi than to grazing horses.[5]
Fossils of it have been found in Nebraska, Colorado, and Montana.[6][7]
20th century restoration by Heinrich Harder.
Life restoration showing a prominent, prehensile upper lip.
^Janis, C. M.; Damuth, J.; Theodor, J. M. (2002). "The origins and evolution of the North American grassland biome: The story from the hoofed mammals". Palaeogeography, Palaeoclimatology, Palaeoecology. 177 (1–2): 183–198. Bibcode:2002PPP...177..183J. doi:10.1016/S0031-0182(01)00359-5.
