Liomys irroratus
Mexican spiny pocket mouse

Liomys irroratus is found mainly in Mexico, though the species has been reported in southern Texas. It ranges from southern Texas in the United States and from southcentral Chihuahua to Oaxaca in Mexico.

This mouse lives in dense vegetation and near rocky mountain slopes or stone fences. It has been found in the dense brush along the banks of the Rio Grande River and beside oxbow lakes, in subtropical palm forests, thickets of prickly pear cactus, and in chaparral. They build burrows that have their opening closed off by vegetation or mounds of dirt.

Liomys irroratus is a medium-sized mouse with rough pelage covering the upper body. The hairs are flattened with sharp points and grooves. The upper fur is dark gray with an orange tint. White fur covers the underside of the mouse except for the heel of the hind foot. The tail is covered with sparse hairs and is bicolored, brown above and white below. They possess external, fur lined, cheek pouches. The dental formula is that of a typical heteromyid rodent: I 1/1, C 0/0, PM 1/1, M 3/3. The average weight of Liomys irroratus is between 50 and 60 grams for males, and between 35 and 50 grams for females. The average total length of this species is 237 mm, with a tail length of 122 mm, and a hind foot length of 30mm.

Little is known about the breeding habits of Liomys irroratus. Litter sizes range from two to eight, with an average of four. Immature individuals are found throughout the year except for the month of May, suggesting that breeding occurs throughout the year.

The Mexican Spiny Pocket Mouse is strictly nocturnal. When food is scarce this species is capable of going into a state of torpor. By dropping body temperature and slowing metabolism it is able to conserve energy and still be active if disturbed.

The Mexican Spiny Pocket Mouse feeds on the seeds of hackberry, mesquite, and other shrubs as well as herbaceous plants. These mice have been known to store seeds in burrows.

None known.

Liomys irroratus is not known to have any adverse affects on human populations.