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,^[1] 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.^[2] According to Wu and coauthors, Propalaeocastor, specifically P. butselensis, is the likely ancestor of the better-known Eurasian castorine Steneofiber.

Propalaeocastor Temporal range: early Oligocene
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Rodentia
Family:	Castoridae
Tribe:	†Anchitheriomyini
Genus:	†Propalaeocastor Borissoglebskaya, 1967
Type species
†Propalaeocastor kazachstanicus
Species
†P. butselensis †P. irtyshensis †P. kazachstanicus †P. shevyrevae †P. zaissanensis
Synonyms
†Asteneofiber Kretzoi, 1974