Propalaeocastor fossil map
Where fossils of Propalaeocastor 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 | 33.9–23.04 million years ago (Rupelian to Chattian) |
| Periods | Paleogene |
| Family | Castoridae |
| Named by | Borisoglebskaya 1967 |
| Fossil records | 20 occurrences at 6 locations (PBDB) |
| Found in | Kazakhstan, China |
| Rock formations | Aral, Keziletuogayi, Burun |
About Propalaeocastor
Propalaeocastor is a poorly known extinct genus of beavers (family Castoridae) from the early Oligocene of Europe and Asia. Recently described material of a new species of Propalaeocastor, P. irtyshensis, indicates the genus is probably the earliest known member of the subfamily Castorinae, which includes all castorids more closely related to living beavers (genus Castor) than to the extinct giant beaver (genus Castoroides). Previously, Propalaeocastor had been allied with more basal beavers such as Agnotocastor and Anchitheriomys. According to Wu and coauthors, Propalaeocastor, specifically P. butselensis, is the likely ancestor of the better-known Eurasian castorine Steneofiber.
Text in “About” is quoted from the Wikipedia article Propalaeocastor (revision 1248772728), 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: Q7250079.