Palaeocastor fossil map
Where fossils of Palaeocastor have been found, shown on the Earth as it looked about 30 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 30 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 | 31.8–16.3 million years ago (Rupelian to Burdigalian) |
| Periods | Paleogene, Neogene |
| Family | Castoridae |
| Named by | Leidy 1869 |
| Fossil records | 170 occurrences at 29 locations (PBDB) |
| Found in | United States, Kazakhstan |
| Rock formations | Sharps, txn:41534, Brule, Gering, John Day, Monroe Creek |
About Palaeocastor
Palaeocastor ('ancient beaver') is an extinct genus of beavers that lived in the North American Badlands during the late Oligocene period to early Miocene, 29.5~18.5 million years ago. Palaeocastor was much smaller than modern beavers. There are several species including Palaeocastor fossor, Palaeocastor magnus, Palaeocastor wahlerti, and Palaeocastor peninsulatus. The animals first became known on grounds of their fossilized burrows, the "Devil's corkscrews."
Text in “About” is quoted from the Wikipedia article Palaeocastor (revision 1302123532), 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: Q2713055.
