The silky pocket mouse, Perognathus flavus, is a small rodent native to the southwestern and west-central United States, as well as to parts of Mexico. The species is quite narrowly distributed in Utah, occurring only in the extreme southeastern corner of the state, in San Juan County. Preferred habitats include sandy soils in arid grassland, woodland, and sagebrush areas.
Silky pocket mice feed almost exclusively on seeds, primarily those of grasses. Similar to other pocket mouse species, the silky pocket mouse has external fur-lined cheek pouches used for temporary food storage. Long-term seed storage occurs in underground burrows.
Breeding occurs throughout the late spring and summer. Gestation lasts about one month, and most females give birth to one litter of approximately four young each year, although multiple litters during a year are possible. Silky pocket mice are primarily nocturnal and solitary.