Canis lupus monstrabilis Goldman
Gray Wolf
1937. Canis lupus monstrabilis Goldman, Jour. Mamm., 18:42, February 11, type from 10 mi. S Rankin, Upton Co., Texas.
Distribution in Tamaulipas.—Probably extinct, recorded only from Matamoros (Goldman, 1944:468).
On the maps of distribution of C. l. monstrabilis published by Leopold (1959:400) and Baker and Villa (1960:370), Tamaulipas is included in the region in which the wolf is considered to be extinct.
Urocyon cineroargenteus scottii Mearns
Gray Fox
1891. Urocyon virginianus scottii Mearns, Bull. Amer. Mus. Nat. Hist., 3:236, June 5, type from Pinal Co., Arizona.
1895. Urocyon cinereo-argenteus scottii, J. A. Allen, Bull. Amer. Mus. Nat. Hist., 7:253, June.
Distribution in Tamaulipas.—All of state in suitable habitats.
The specimen from the Sierra Madre Oriental was obtained by a collector who used a rabbit call. Leopold (1959:408) reported that the highest elevation [about 2800 feet] at which he found gray fox in México was at Hacienda de Acuña, in the Sierra de Tamaulipas, where "dense, brushy draws and oak openings made ideal habitat." At this place Leopold saw, in early August, a family of foxes, four well-grown young and their parents. Dice (1937:250) reported U. c. texensis (a junior synonym of U. c. scottii), as abundant in the Sierra San Carlos.
The six specimens examined do not present any significant difference in size and shape of the skull from specimens of scottii from Arizona, except that one skull from the Sierra de Tamaulipas is smaller than the others, suggesting intergradation between the subspecies scottii and tropicalis from farther south.