Key to the Regional Pocket Gophers


1. Upper incisors lacking conspicuous longitudinal grooves: Thomomys, 2

1'. Upper incisors with one or more conspicuous longitudinal grooves: 4

2. Found in the higher parts of the Animas Mountains, Hidalgo County, and adjacent highlands in southeastern Arizona: Thomomys umbrinus.

2'. Found elsewhere or at lower elevations: 3

3. Color yellowish, brownish, or blackish; anterior openings of infra-orbital canals not posterior to anterior palatine foramina: Thomomys bottae.

3'. Color grayish or brownish; anterior openings of infraorbital canals posterior to anterior palatine foramina: Thomomys talpoides.

4. Upper incisors each with one longitudinal groove: Cratogeomys castanops.

4'. Upper incisors each with two longitudinal grooves: Geomys bursarius, Geomys arenarius, Geomys knoxjonesi (cryptic species).

Key modified from Findley (1987).


Last Update: 5 Jan 2008