Mountain Beaver

About the Mountain Beaver

The mountain beaver (Aplodontia rufa) or sewellel 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. There are seven subspecies of mountain beaver, six of which are found in California and three of which are endemic to the state.

The name sewellel was recorded by Lewis and Clark who misunderstood the Chinook word [ʃʔulal] (which they annotated as "she-wal-lal"), the name for garments made from their skin; the Chinook themselves call it "ogwoolal" (pronounced [əɡʷulal]). "Mountain beaver" is a misnomer as the animal is not a true beaver nor restricted to mountains.

The name Aplodontia ("simple tooth") is in reference to the single large basin comprising the bulk of each cheek tooth. The specific epithet, rufa, means red or reddish. Most references use the spelling "Aplodontidae" for the family name. This has been deemed incorrect due to the technical rules of converting a genus name into a family name. The proper conversion of Aplodontia... Wikipedia →