Cactus mouse

Description

The cactus mouse (Peromyscus eremicus) is a species of rodent in the family Cricetidae. It is a species of the genus Peromyscus, a closely related group of New World mice often called "deermice" (although the term more commonly refers specifically to P. maniculatus). They are native to desert areas of western North America. Cactus mice are small cricetid rodents, with large eyes and ears, a pointed snout, and a long monocolor tail. Total length, 160mm to 211mm; length of body, 72mm to 100mm; length of tail, 84mm to 120mm; length of hind foot, 18mm to 22mm; length of ear, 13.4mm to 20.0mm; greatest length of skull, 22.7mm to 25.9mm and zygomatic breadth, 11.2mm to 13.5mm. Adults weigh between 18 and 40 grams (0.63 and 1.41 oz). Females weigh slightly more than males and are significantly larger in body length, ear length, length of mandible, and bullar width of skull. Cactus mice can be identified by having naked soles on their hind feet and almost naked flesh-colored tails (as opposed to the furry bicolored tail common in most Peromyscus species), which are usually the same length or longer than the animals' body length. Their ears are nearly hairless, large, and membranous. Their fur is long and soft; coloration varies between subspecies and between different populations. Color of fur varies from ochre to cinnamon, with white ventral areas, and the sides and top of head slightly grayish. Females tend to be slightly paler in color than males, while juveniles appear more gray than their parents. Cactus mice are found in dry desert habitats, steppe, and mountain foothills in arid regions of the southwestern United States and northern Mexico, as well as islands off the coast of the Baja California peninsula and in the Gulf of Mexico. Low average temperatures and lack of the mesquite species Prosopis juliflora might limit northern expansion. The cactus mouse occurs sympatrically with five other mouse species, including the California mouse, canyon mouse, Eva's desert mouse, mesquite mouse, and the western deermouse.