Phyllotis definitus Osgood, 1915 . Field Mus. Nat. Hist. Publ. Zool. Ser., 10: 189.

TYPE LOCALITY: Peru, Ancash Dept., Macate, 9000 ft. (2743 m) .

DISTRIBUTION: Andes of Ancash Dept. (Peru).

COMMENT: Formerly included in magister (see Pearson, 1958, Univ. Calif. Publ. Zool., 56(4):431) and in darwini (see Hershkovitz, 1962, Fieldiana Zool., 46:296), but see Pearson, 1972, J. Mammal., 53:680-682, and Pearson and Patton, 1976, J. Mammal., 57:339-350.