Hipparionini

Hipparionini is an extinct tribe of three-toed equids in the subfamily Equinae. They had body forms similar to modern equines, with high-crowned teeth. They first appeared in North America during the Early Miocene around 17 million years ago, before migrating into the Old World around 11.4-11.0 million years ago. The youngest species date to the end of the early Early Pleistocene, becoming extinct following the arrival of modern equines of the genus Equus to the Old World.

== Description == left|thumb|253x253px|Leg of Cormohipparion, showing the three functional digits Hipparionines varied widely in size, with the smallest species having a body mass of under , comparable to sheep, while the largest species had body masses over . Unlike modern horses, but like many other fossil equids, they bore three toes on each foot, with the two side digits being considerably smaller than the main central toe. Evidence from preserved trackways suggests that the side digits were functional rather than merely vestigial and contacted the ground, and may have been used for joint stabilization and load bearing, and may have aided movement when needing to change direction. It has been suggested that the underside of the central hoof had a frog like modern equines. Their teeth are somewhat lower crowned compared to modern equines, though they had relatively complex enamel patterns that exceed the enamel complexity of teeth of members of the tribe Equini, which is thought to have been an adaption to increasing wear resistance. Compared to modern equines, the metapodial bones of the leg/foot were longer, as is ancestrally found in equids. Some Old World hipparionines like Proboscidipparion developed retracted nasals and elongated snouts that may indicate the presence of a tapir-like proboscis.