Cynomys ludovicianus (Ord, 1815) . In Guthrie, A New Geogr., Hist. Coml. Grammar, Phila., 2nd ed., 2: 292.

TYPE LOCALITY: U.S.A., “Upper Missouri River."

DISTRIBUTION: Saskatchewan (Canada); Montana to E. Nebraska, W. Texas, New Mexico, and S.E. Arizona (U.S.A.); N. E. Sonora, and N. Chihuahua (Mexico).

COMMENT: Subgenus Cynomys; see Hall, 1981:411.

ISIS NUMBER: 5301410002004003001.