Ptilodus fossil map
Where fossils of Ptilodus have been found, shown on the Earth as it looked about 56 million years ago and on today’s map.
Dots are fossil collections recorded in the Paleobiology Database. The “then” view moves today’s fossil sites back to their positions 56 million years ago (the time slice nearest the median age of the fossils) using the Merdith et al. (2021) plate model; positions are approximate. Open on the timeline map →
| Group | Early mammals |
|---|---|
| Lived | 66–56 million years ago (Danian to Thanetian) |
| Periods | Paleogene |
| Family | Ptilodontidae |
| Named by | Cope 1881 |
| Fossil records | 198 occurrences at 61 locations (PBDB) |
| Found in | United States, Canada |
| Rock formations | Fort Union, txn:39810, Paskapoo, Ferris, Black Peaks, Ravenscrag |
About Ptilodus
Ptilodus (meaning "soft-haired") is an extinct genus of mammals from the extinct order of Multituberculata, and lived during the Palaeocene in North America.
Ptilodus was a relatively large multituberculate of 30 to 50 centimetres (12 to 20 in) 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.
Like other ptilodontids, it had a very large and elongated last lower premolar which formed a serrated slicing blade.
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.
Text in “About” is quoted from the Wikipedia article Ptilodus (revision 1368551979), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 23 October 2026. Ages are those of the rock layers the fossils were found in. Wikidata: Q783958.
