Pappogeomys castanops (Baird, 1852) . Rept. Stansbury's Expl. Surv. Grt. Salt Lake Utah, App. C, p. 313.

TYPE LOCALITY: U.S.A., Colorado, Bent Co., along prairie road to Bent's Fort, near present town of Las Animas .

DISTRIBUTION: S.E. Colorado and S.W. Kansas (U.S.A.) to N. Tamaulipas and C. San Luis Potosi (Mexico). Colima (Mexico) (JRP).

COMMENT: May represent two species; see Berry and Baker, 1972, J. Mammal., 53:303-309.

ISIS NUMBER: 5301410003006003001.