Palaeocastor

Palaeocastor
Temporal range: Late Oligocene to Early Miocene,
P. fossor, collected in Wyoming. At the American Museum of Natural History
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Castoridae
Subfamily: Palaeocastorinae
Genus: Palaeocastor
Leidy, 1869
Species
  • P. fossor
  • P. peninsulatus

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."