Mountain beaver

The mountain beaver (Aplodontia rufa) is a North American rodent. It is the only living member of its genus, Aplodontia, and family, Aplodontiidae. It should not be confused with true North American and Eurasian beavers, to which it is not closely related; the mountain beaver is instead more closely related to squirrels, although its less-efficient renal system was thought to indicate greater relative antiquity for the species. There are seven subspecies of mountain beavers, six of which are found in California and three of which are endemic to the state.