What is "ptilodus"

Ptilodus is a genus of mammals from the extinct order of Multituberculata, and lived during the Paleocene in North America.

Ptilodus was a relatively large multituberculate of in length, which is about the same size as a squirrel. Its feet, legs and long tail suggest it was a good climber, so it very possibly led a squirrel-like lifestyle.

The genus was named by paleontologist Edward Drinker Cope in 1881. Cope also mistakenly assigned some material belonging to this genus to Chirox in 1884. Elements from Ectypodus (Jepsen, 1940) and Neoplagiaulax have also been reassigned to this genus.