Orthogeomys Merriam, 1895 . N. Am. Fauna, 8:172.

TYPE SPECIES: Geomys scalops Thomas, 1894 .

SYNONYMS: Heterogeomys Merriam, Macrogeomys Merriam.

COMMENTS: Russell (1968a) revised the genus, and included Heterogeomys and Macrogeomys as valid subgenera. Biochemical systematics of species of subgenus Macrogeomys was presented by Hafner (1991). Species limits are poorly defined, as most are known from single localities or otherwise geogeographically restricted areas.