Merychippus, extinct genus of early horses, found as fossils in deposits from the Middle and Late
Where did Merychippus live and when?
Merychippus is an extinct proto-horse of the family Equidae that was endemic to North America during the Miocene, 15.97–5.33 million years ago. It had three toes on each foot and is the first horse known to have grazed.
When did Pliohippus live?
Fossils of Pliohippus are found at many late Miocene localities in Colorado, the Great Plains of the US (Nebraska and the Dakotas) and Canada. Species in this genus lived from 12-6 million years ago.