Order Rodentia - Family Geomyidae Author James L. Patton text 1993 Smithsonian Institution Press Washington and London Editor Don E. Wilson Editor DeeAnn M. Reeder Mammal Species of the World (2 nd Edition) 469 476 book chapter 193478 10.5281/zenodo.7353077 cfa9a295-fcad-4633-a3d9-26b72bae5d1a 1-56098-217-9 7353077 Thomomys Wied-Neuwied, 1839 . Nova Acta Phys.-Med. Acad. Caes. Leop.-Carol., 19(1):377 . TYPE SPECIES: Thomomys rufescens Wied-Neuwied, 1939 (= T. talpoides rufescens ). SYNONYMS: Megascapheus Elliot, 1903 . COMMENTS: Recent species allocated to two subgenera ( Thaeler, 1980 ): Thomomys , which includes the species talpoides , clusius , idahoensis , mazama , and monticola ; and Megascapheus including bottae, bulbivorus, townsendii, and umbrinus. Phylogenetic relationships among members of the subgenus Megascapheus were presented by Patton and Smith (1981) , based on molecular data. Specific boundaries for some forms are poorly defined, but Patton and Smith (1989) provided an operational definition that can be applied to all pocket gophers.