1911. Liomys irroratus alleni, Goldman, N. Amer. Fauna, 34:56, September 7.
Distribution in Tamaulipas.—Extreme southwestern part of state.
This subspecies is easily distinguished from L. i. texensis by the following features: hind foot larger, 31.5 (30-33.5) instead of 27.8 (27-29); skull longer, 34.2 (32.4-36.4) instead of 31.5 (30.0-32.5); maxillary tooth-row longer, 5.4 (5.0-5.8) instead of 5.0 (4.8-5.1); interorbital constriction relatively narrower in alleni. Intergradation between L. i. alleni and L. i. texensis takes place at Rancho Santa Rosa (where, of the two specimens, one is conspicuously larger than the other), eight kilometers northeast of Antiguo Morelos, El Encino, and Ejido Santa Isabel. All specimens from the localities mentioned are here assigned to texensis.
Weight of three pregnant females averaged 68.9 (64-78) grams, that of non-pregnant females, 65.6 (64-68), and that of six males 73.0 (65-80).
Records of occurrence.—Specimens examined, 34: Villa Mainero, 1700 ft., 2; Nicolás, 56 km. NW Tula, 5500 ft., 6; Jaumave, 2400 ft., 23; 16 mi. N, 6 mi. W Palmillas, 5500 ft., 1; 14 mi. N, 6 mi. W Palmillas, 5500 ft., 2.
Additional records: Miquihuana (Goldman, 1911:56); Tula (Hooper and Handley, 1958:18).
Liomys irroratus texensis Merriam
1902. Liomys texensis Merriam, Proc. Biol. Soc. Washington, 15:44, March 5, type from Brownsville, Cameron Co., Texas.
1911. Liomys irroratus texensis, Goldman, N. Amer. Fauna, 34:59, September 7.
Distribution in Tamaulipas.—State-wide except extreme southwestern and northwestern parts.