Thomomys townsendii (Bachman, 1839) . J. Acad. Nat. Sei. Phila., 8:105.

TYPE LOCALITY: U.S.A., Idaho, Canyon Co., near Nampa .

DISTRIBUTION: S.E. Idaho; S.W. Idaho; S.E. Oregon, N. Nevada, and N.E. California (U.S.A.).

COMMENT: Revised by Davis, 1937, J. Mammal., 18: 145-158. Considered a distinct species by Thaeler, 1968, Evolution, 22:543-555, who provided evidence of a zone of hybridization between bottae and townsendii . Hall, 1981:469, 495, reviewed this evidence and included townsendii in umbrinus (sensu Hall) . Includes similis which may be a distinct species (RDO).

ISIS NUMBER: 5301410003007008001.