Xerospermophilus tereticaudus (Baird, 1858)

Common Name and Taxon Classification

Xerospermophilus tereticaudus, commonly known as the round-tailed ground squirrel, is a very small species of ground squirrel.

Weight

Newborns weigh approximately 3.9 grams (0.14 oz), while adults weigh around 125 grams (4.4 oz).

Distinctive Appendages

All individuals have a long round tail and long, hairy hind feet.

Dorsal Coloration

This species has no fur markings, and instead has a uniform sandy color that matches the soil where it burrows.

Ventral Coloration

The underside of its body is usually a lighter shade.

Body Length

The average total length of round-tailed ground squirrels, including the tail, ranges from 204 to 278 millimetres (8.0 to 10.9 in); their tails alone measure 60 to 112 millimetres (2.4 to 4.4 in) long.

Reproduction

The species has a gestation period of 28 days, and an average of 5.4 pups are born per litter.

Sexual Maturity

Round-tailed ground squirrels reach sexual maturity at 325 days.

Longevity

There is little published information on the natural longevity of this species, but one wild-born specimen lived to approximately 8.9 years while in captivity.

Predators

This species is a common prey animal for coyotes, badgers, hawks, and snakes.

Parasites

Round-tailed ground squirrels have been found infected with the coccidian parasite Eimeria vilasi, a parasite normally found in other rodents and Old World marmotine rodents.