Diacodexis

Diacodexis is an extinct genus of small herbivorous mammals belonging to the family Diacodexeidae  that lived in North America, Europe and Pakistan from 55.4 mya to 46.2 mya and existing for approximately.

Description
Diacodexis is the oldest known even-toed ungulate. In life, it would have resembled a modern duiker, measuring about 50 cm in body length, but with a much longer tail. Unlike most later species of artiodactyl, it still had five toes on each foot, although the third and fourth toes were already elongated. It may also have had small hooves on each toe. Its teeth suggest that it was a herbivorous browser.

As suggested by its long legs, Diacodexis is believed to have been fast-running, capable of leaping relatively far.

Fossil distribution
Diacodexis was widespread, with fossils having been found in Pakistan, Europe, and North America.