Peromyscus leucopus texanus (Woodhouse)
White-footed Mouse
1853. Hesperomys texana Woodhouse, Proc. Acad. Nat. Sci. Philadelphia, 6:242, type probably from vicinity of Mason, Mason Co., Texas.
1909. Peromyscus leucopus texanus, Osgood, N. Amer. Fauna, 28:127, April 17.
Distribution in Tamaulipas.—Over all of state.
This is the most common species of the genus Peromyscus in Tamaulipas. It and Liomys irroratus are the two rodents most easily trapped throughout the state. In general P. l. texanus occurs in forested and brushy areas especially under 1200 feet in elevation, as was noted in the Sierra de Tamaulipas, where P. l. texanus was taken commonly at elevations of up to 1200 feet. Above this elevation the species was rare and P. pectoralis and P. boylii were more abundant than at lower elevations. The three specimens of P. l. texanus from 12 kilometers north and four kilometers west of Ciudad Victoria were trapped in a line of 110 traps set near tree stumps. Small burrows in the ground were noted here. The forest at this locality was composed of mesquite, ebony, acacias, a few yuccas and "nopales" (= cactuses); the ground was covered by cat claw.
Of the many young taken, 15 specimens were saved from Ejido Santa Isabel where P. leucopus was abundant in an area of chaparral consisting of wild "tomate," "zapote," "huizache" and "salvadora." Most of the specimens caught at this locality were taken between 7:30 and 9:30 p. m. in traps baited with a mixture of rolled oats, peanut butter and banana. Specimens from 53 kilometers north of El Limón were taken along with Liomys irroratus; the specimen from two kilometers west of El Carrizo was trapped near a dead mesquite log. Reitrodontomys fulvescens was taken in the same area. Four specimens of P. leucopus were taken at Rancho Pano Ayuctle, around a big pile of old firewood in an abandoned sugar mill. At the locality six miles north and six miles west of Altamira, P. leucopus was found in cultivated fields and along the grassy roadsides; in the vicinity of Tampico specimens were taken in an area of forested cactus-thorn. The specimen from seven kilometers south and two kilometers west of San Fernando was found in a trap set at the base of "nopal" cactus, which was surrounded by bushes and small trees (10-12 feet high).
Breeding records are as follows: Rancho Pano Ayuctle, on February 15, one female carried 2 embryos of 23 mm. in crown-rump length; Jaumave, July 26 to 29, five females, averaging 4.6 (3-6) embryos of 7 (3-15) mm., two females lactating, one on May 25 and the other on July 26; Ejido Santa Isabel, on January 20 to 25, three females lactating; Soto la Marina, on May 16, one female lactating.
Average weights were as follows: from Jaumave four pregnant females, 28.0 (25-33), eight males, 23.4 (21-27); from the Sierra de Tamaulipas, eight females non-pregnant, 21.2 (18-26), 14 males, 22.0 (19-27); from 6 mi. N, 6 mi. W Altamira, six males, 23.5 (21-27).
All specimens examined from Tamaulipas are assigned to P. l. texanus because their coloration is pale. Even so the color varies some according to locality; specimens from Rancho Pano Ayuctle and the Sierra de Tamaulipas have much of the cinnamon color that is characteristic of P. l. incensus from farther south, but even so specimens from the two localities last mentioned are paler than those from Veracruz that are typical incensus.