Taxa Count: 7

CASTORIDAE

Agnotocastor Stirton, 1935

Agnotocastor coloradensis Wilson, 1949

Euroxenomys Samson & Radulesco, 1973

Hystricops Leidy, 1858

Monosaulax Stirton, 1935

Monosaulax curtus (Matthew & Cook, 1909)

Palaeocastor Leidy, 1869