Thomomydoecus (Thomomydoecus) williamsi (Price & Hellenthal, 1980)

Geomydoecus (Thomomydoecus) williamsi Price & Hellenthal, 1980a: 308, figs 15, 22. Tlaxcala: Thomomys umbrinus, 9 km N, 8 km E of Apizaco, 23 Mar. 1978, S.L. Williams; 9 km N, 8 km E Apizaco, 19 km W Tlaxcala, no date; 9 km N, 7 km E Apizaco, 19 km W Tlaxcala, no date; 10 km N, 9 km E Apizaco, 19 km W Tlaxcala, no date (Price & Hellenthal 1980a).

Type: Holotype male deposited in USNM.