After McKenna & Bell, 1997, with Recent species from Nowak, 1991

<==o Thomomyini R.J. Russell, 1968
   `--o Thomomys Wied-Neuwied, 1839 [Tomomys Brandt, 1855] [incl. Megascapheus Elliot, 1903; †Plesiothomomys Gidley & Gazin, 1933] L.Plioc.-R. NA. (western pocker gophers, smooth-toothed pocket gophers; taskurotat)
      |-- †T. sp.
      |-- †T. carsonensis Kelly, 1994
      |-- †T. gidleyi R. Wilson, 1933
      |-- †T. microdon Sinclair, 1905
      |-- †T. orientalis Simpson, 1928
      |-- †(Plesiothomomys) potomacensis (Gidley & Gazin, 1933) Kurten & Anderson, 1980
      |--o (Megascapheus) Elliot, 1903
      |  |-- T. (M.) talpoides [Cricetus talpoides Richardson, 1828; Thomomys talpoides (Richardson) Kurten & Anderson, 1980] (mountain pocket gopher)
      |  |-- T. (M.) idahoensis (idahontaskurotta)
      |  |-- T. (M.) clusius (coues pocket gopher)
      |  |--o T. (M.) mazama (mazama pocket gopher)
      |  |  |-- †T. (M.) m. tacomensis
      |  |  `-- T. (M.) m. mazama ()?
      |  `-- T. (M.) monticola (vuoritaskurotta)
      `--o (Thomomys)
         |-- T. (T.) bulbivorus (pohjantaskurotta)
         |-- T. (T.) bottae (Eydoux & Gervais, 1836) [Oryctomys bottae Eydoux & Gervais, 1836; Thomomys bottae (Eydoux & Gervais) Kurten & Anderson, 1980] (laaksotaskurotta)
         |-- T. (T.) townsendii (Bachman, 1839) [Geomys townsendii Bachman, 1839; Thomomys umbrinus Hall, 1981; Thomomys townsendii (Bachman) Thaeler, 1968, Kurtén & Anderson, 1980, Patton et al., 1984, Patton & Smith, 1989, Rogers, 1991, and D. Wilson & Reeder, 1993] (townsend's pocket gopher)
         `-- T. (T.) umbrinus (Richardson, 1829) [Geomys umbrinus Richardson, 1829; Thomomys umbrinus (Richardson) Kurten & Anderson, 1980; incl. Thomomys townsendii (Bachman) sensu Hall, 1981] (meksikontaskurotta)

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