Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels, and flying squirrels. Squirrels are indigenous to the Americas, Eurasia, and Africa, and were introduced by humans to Australia. The earliest known fossilized squirrels date from the Eocene epoch, and among other living rodent families, the squirrels are most closely related to the mountain beaver and to the dormice.
The California ground squirrel, also known as the Beechey ground squirrel, is a common and easily observed ground squirrel of the western United States and the Baja California Peninsula; it is common in Oregon and California and its range has relatively recently extended into Washington and northwestern Nevada. Formerly placed in Spermophilus, as Spermophilus beecheyi, it was reclassified in Otospermophilus in 2009, as it became clear that Spermophilus as previously defined was not a natural (monophyletic) group. A full species account was published for this species in 2016.
Ground squirrels are rodents of the squirrel family (Sciuridae) that generally live on the ground or in burrows, rather than in trees like the tree squirrels. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known as marmots or prairie dogs, while the smaller and less bushy-tailed ground squirrels tend to be known as chipmunks.
Franklin's ground squirrel is a species of squirrel native to North America, and the only member of the genus Poliocitellus. Due to the destruction of prairie, the populations of Franklin's ground squirrel have dwindled, approaching levels of concern. Its decline in the eastern portion of its range is mostly attributed to habitat fragmentation.
The Arctic ground squirrel is a species of ground squirrel native to the Arctic and Subarctic of North America and Asia. People in Alaska, particularly around the Aleutians, refer to them as "parka" squirrels, most likely because their pelt is good for the ruff on parkas and for clothing.
The thirteen-lined ground squirrel, also known as the striped gopher, leopard ground squirrel, and squinny, is a ground squirrel that is widely distributed over grasslands and prairies of North America.
The tropical ground squirrel is a species of rodent in the family Sciuridae. At one time the species was originally described as Spermophilus adocetus, but the genus Spermophilus was revised and subdivided in 2009 and it was placed in the genus Notocitellus. It is endemic to arid upland areas and deciduous woodland in Mexico. It is locally referred to as Cuinique.
The ring-tailed ground squirrel is a species of rodent in the family Sciuridae. It is endemic to the Pacific coast region of central Mexico. It is a common species and feeds mainly on fruits and nuts. The IUCN has assessed it as being of "least concern".
The Baja California rock squirrel is a species of rodent in the family Sciuridae. It is endemic to Baja California, Mexico.
The Columbian ground squirrel is a species of rodent common in certain regions of Canada and the northwestern United States. It is the second largest member of the genus Urocitellus, which is part of the tribe Marmotini, along with marmots, chipmunks, prairie dogs, and other holarctic ground squirrels. They are stout, with short dense fur, which is characteristically tawny across the bridge of the nose. Social encounters sometimes are initiated with kissing behavior and the most common activity above ground is standing at attention. Residing in mountainous terrain and high plains in northern latitudes, they hibernate for 8 to 9 months of the year in burrows, which may be used for many years. They are emaciated when emerging in the spring. The Columbian ground squirrel came to the attention of the scientific community through writings produced by Lewis and Clark, while 21st century molecular genetics has more finely illuminated its ties with other close relatives.
The Sierra Madre ground squirrel is a species of rodent in the squirrel family. It is endemic to the Sierra Madre Occidental, in northern Mexico. Its natural habitat is subtropical or tropical dry lowland grassland.
The speckled ground squirrel or spotted souslik is a species of rodent in the family Sciuridae from Eastern Europe. Spermophilus suslicus consists of three subspecies: S. s. boristhenicus, S. s. guttatus, and S. s. suslicus. It is threatened by habitat loss.
The rock squirrel is a species of rodent in the family Sciuridae. It is native to Mexico and the Southwestern United States, including southern Nevada, Utah, Colorado, Arizona, New Mexico, West Texas, and the panhandle of Oklahoma.
The Xerinae comprise a subfamily of squirrels, many of which are highly terrestrial. It includes the tribes Marmotini, Xerini, and Protoxerini.
Otospermophilus is a genus of ground squirrels in the family Sciuridae, containing three species from Mexico and the United States. Otospermophilus was formerly placed in the large ground squirrel genus Spermophilus, as a subgenus or species group. Since DNA sequencing of the cytochrome b gene has shown Spermophilus to be paraphyletic to the prairie dogs and marmots, it is now separated, along with six other genera.
Notocitellus is a genus of ground squirrels, containing two species from Mexico. These species are the tropical ground squirrel, and the ring-tailed ground squirrel (N. annulatus). Notocitellus was formerly placed in the large ground squirrel genus Spermophilus, as a subgenus or species group. Since DNA sequencing of the cytochrome b gene has shown Spermophilus to be paraphyletic to the marmots, antelope squirrels, and prairie dogs, it is now separated, along with six other genera. The exact relations of this genus are unclear, though a relation to the antelope squirrels is possible.
Pygmy ground squirrels are small ground squirrels in the genus Xerospermophilus, family Sciuridae, containing four species from Mexico and the United States. The members of this genus were formerly placed in the large ground squirrel genus Spermophilus. Since DNA sequencing of the cytochrome b gene showed that Spermophilus was paraphyletic to the prairie dogs and marmots, this group is now separated, along with six other genera. Within the genus, the Mohave ground squirrel and the round-tailed ground squirrel were thought to be close relatives, sometimes a subgenus Xerospermophilus, while the spotted ground squirrel and the Perote ground squirrel were formerly placed in the subgenus Ictidomys.
Urocitellus is a genus of ground squirrels. They were previously believed to belong to the much larger genus Spermophilus, but DNA sequencing of the cytochrome b gene showed that this group was paraphyletic to the prairie dogs and marmots, and could therefore no longer be retained as a single genus. As a result, Urocitellus is now considered as a genus in its own right.
Ictidomys is a North American genus of rodent in the squirrel family, which contains the thirteen-lined ground squirrel, the Mexican ground squirrel, and the Rio Grande ground squirrel. These species were included in the species-rich ground squirrel genus Spermophilus until molecular data showed that this genus was not a natural, monophyletic grouping.
The Rio Grande ground squirrel is a species of squirrel in the family Sciuridae. It is found in the south-western United States and in north-eastern Mexico.
