Ctenomys opimus Wagner, 1848 . Arch. Naturgesch., 1:75.

TYPE LOCALITY: Bolivia, Oruro Dept., Monte Sajama .

DISTRIBUTION: NW Argentina, SW Bolivia, S Peru, N Chile between 2,000 and 5,000 m elevation on the high Andean steppe (= Puna).

STATUS: Common.

SYNONYMS: luteolus.

COMMENTS: May be conspecific with fulvus; opimus and fulvus cannot be separated on the basis of karyotypes; see Gallardo (1979:80) and Cook et al. (1990). The chromosome no. is 2n=26; FN=48.