Microsyops fossil map
Where fossils of Microsyops 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 | 56–39.7 million years ago (Ypresian to Bartonian) |
| Periods | Paleogene |
| Family | Microsyopidae |
| Named by | Leidy 1872 |
| Fossil records | 474 occurrences at 69 locations (PBDB) |
| Found in | United States |
| Rock formations | Willwood, Wasatch, Bridger, Wind River, DeBeque, Aycross |
About Microsyops
Microsyops is a plesiadapiform found in the Middle Eocene in North America. It is in the family Microsyopidae, a plesiadapiform family characterized by distinctive lanceolate lower first incisors. It appears to have had a more developed sense of smell than other early primates. It is believed to have eaten fruit, and its fossils show the oldest known dental cavities in a mammal.
There are nine species of Microsyops that exist in the fossil record from the middle Wasatchian (~53 million years ago) through Uintan (~42 million years ago) North American Land Mammal Ages. Microsyops is primarily known from the Rocky Mountain region of the United States, though fossils have also been found in California and Texas.
Text in “About” is quoted from the Wikipedia article Microsyops (revision 1368884896), 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: Q28455296.
