The Texas mouse is considered medium-sized for its genus. It has long tail, bicolored, upper tail has brownish, and lower tail has brownish white with well haired. Also slightly tufted at the end; large hind feet. It has usually dark or dusky ankles, and the ear is medium-sized. Color of dorsal is dark mixed with brown and blackish hairs, and side color is pinkish cinnamon, and belly and feet have pure white color. The mouse morphological adapted to have long tail as balancing when they climb vertical surface, and large eye as activating in darkness. Adult Peromyscus attwateri's total length is usually about 182 to 220 mm with weight 25-35 grams. The tail is about 83-104mm, ear length is about 18–20 mm, and length of hind foot is about 24–27 mm. Texas mouse found in Missouri. The specimen is a male measuring 171 mm of total length, 89 mm of tail, 23 mm of hind foot, and 19 mm of ear by Dr. Hershel W. Morphological size variation in Texas mouse appears related with assemblage of physiologic and ecologic factors. Their skull is large length in 27.6 to 30.4 mm, and they have wide and not rounded braincase. Also, they have large pterygoid fossa, medium auditory bullae that larger than in P. maniculatus and P. leucopus but smaller than in P. true.
Ecology
Range and Habitat
Texas mouse, Peromyscus attwateri, is found in western Arkansas, southeastern Kansas, southern Missouri, south-central and northeastern Oklahoma in forest, and Texas. They inhibits not only rocky areas with high cliffs and slopes under juniper, but also limestone with woody such as oak and black hickory vegetation because of predators. Cedar glades and hard wood forest is primary habitat. Estimated population density is 0.7 to 5.4 ha at different seasons in various regions. The average home range that of Texas mouse is 0.2 ha, and the male home range is twice of female.
Diet
The Texas mouse is omnivorous. Acorns tend to often used food in winter and spring, and their diet is variety of animal and plant from natural depending on availability. To get a source of nutrition, it may be eaten that berries, seeds, flowers, nuts, fruits, and insects importantly.
Behavior
Texas mouse is mostly nocturnal, and does not hibernate. They have morphological adaptations in movement on the tree for climbing with long tail and hind feet; they spend 70 percents of time by climbing tree.
Reproduction
Texas mouse's breeding period occurs in autumn and spring, but there is limited breeding in winter season. There is no evidence that breeding during the late spring and summer. They can breed multiple times during the available seasons and the pregnancy period, gestation, lasts 23 days in non lactating, after 23 days, it will start lactating for about 8 days. Normally, the average number of young per litter is three or four. However, Latter size in Texas mouse shows seasonal variation. Relatively, female collected in winter few embryos than spring. The young of the mouse is weight about 1.5 g with hairless, not opened eyes, and pinkly skin. Their hair start to grow after two days, and two weeks after closed eyes will be opened. A month after, their young are weaned, and they leave the nest in order to live alone. On the other hand, some young live together with mother for a long time. all of young leave the nest and to be independent young from their mothers.
