Perognathus is a genus of pocket mouse. Like other members of their family

Heteromyidae

The family of rodents that include kangaroo rats, kangaroo mice and rock pocket mice is the Heteromyidae family. Most heteromyids live in complex burrows within the deserts and grasslands of western North America, though species within the Heteromys and Liomys genera are also found in forests and...

 they are more closely related to pocket gopher

Pocket gopher

The pocket gophers are burrowing rodents of the family Geomyidae. These are the "true" gophers, though several ground squirrels of the family Sciuridae are often called gophers as well...

s than to true mice

Mouse

A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...

.

Characteristics

The silky pocket mice are small animals with soft pelage, long tails, and small feet compared to other heteromyids. They have long claws which are used for digging burrows and sifting sandy substrates for seeds. They have also been found to steal seeds from kangaroo rat

Kangaroo rat

Kangaroo rats, genus Dipodomys, are small rodents native to North America. The common name derives from their bipedal form: as they hop in a manner similar to the much larger kangaroo, although they are not related...

s' dens.http://www.livescience.com/animalworld/060811_desert_thieves.html They store these seeds in large hairy external cheek pouches. They are nocturnal and are found in arid habitats. They are not true hibernators

Hibernation

Hibernation is a state of inactivity and metabolic depression in animals, characterized by lower body temperature, slower breathing, and lower metabolic rate. Hibernating animals conserve food, especially during winter when food supplies are limited, tapping energy reserves, body fat, at a slow rate...

, but will go into torpor

Torpor

Torpor, sometimes called temporary hibernation is a state of decreased physiological activity in an animal, usually characterized by a reduced body temperature and rate of metabolism. Animals that go through torpor include birds and some mammals such as mice and bats...

 and stay in their burrows for extended periods of time.

Species

• Perognathus alticola – White-eared Pocket Mouse
• Perognathus amplus – Arizona Pocket Mouse
• Perognathus fasciatus – Olive-backed Pocket Mouse
• Perognathus flavescens – Plains Pocket Mouse
• Perognathus flavus – Silky Pocket Mouse
• Perognathus inornatus – San Joaquin Pocket Mouse
• Perognathus longimembris – Little Pocket Mouse
• Perognathus merriami – Merriam's Pocket Mouse
• Perognathus parvus – Great Basin Pocket Mouse

Sometimes members of the genus Chaetodipus

Chaetodipus

Chaetodipus is a genus of pocket mouse containing 19 species endemic to the United States and Mexico. Like other members of their family such as pocket mice in the genus Perognathus, they are more closely related to pocket gophers than to true mice....

are placed in Perognathus.