Squirrels are members of the family Sciuridae, a family that includes small or medium-sized 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.
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.
Spermophilus is a genus of ground squirrels in the squirrel family. As traditionally defined the genus was very species-rich, ranging through Europe, Asia and North America, but this arrangement was found to be paraphyletic to the certainly distinct prairie dogs, marmots, and antelope squirrels. As a consequence, all the former Spermophilus species of North America have been moved to other genera, leaving the European and Asian species as true Spermophilus.
The European ground squirrel, also known as the European souslik, is a species from the squirrel family, Sciuridae. It is among the few European species in the genus Spermophilus. Like all squirrels, it is a member of the rodent order. It is to be found in eastern and central Europe from southern Ukraine, to Asia Minor, Austria, the Czech Republic, Slovakia, Serbia, Greece, Romania, Bulgaria, North Macedonia and north as far as Poland but the range is divided in two parts by the Carpathian Mountains.
The Indian giant flying squirrel, also called the large brown flying squirrel or the common giant flying squirrel, is a species of rodent in the family Sciuridae. It is capable of gliding flight using a skin membrane, the patagium, stretched between front and hind legs. It is found in mainland Southeast and South Asia, and southern and central China.
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 Alashan ground squirrel is a species of squirrel. It is native to China and Mongolia.
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 Daurian ground squirrel is a species of rodent in the family Sciuridae. It is found in China, Mongolia, and Russia.
The red-cheeked ground squirrel is a species of rodent in the family Sciuridae. It is commonly referred to as the red-cheeked ground souslik and there are several recognized subspecies. It is found in central Asia. Spermophilus brunnescens, Spermophilus heptneri and Spermophilus ungae are accepted as synonyms. There is some controversy over whether Spermophilus pallidicauda and Spermophilus brevicauda should be regarded as synonyms or full species.
The russet ground squirrel is a species of rodent in the family Sciuridae. It is also known as the hibernating large ground squirrel and the large-toothed souslik. It is found in west central Asia where its natural habitat is temperate grassland.
The little ground squirrel or little souslik, is a species of rodent in the family Sciuridae. It is found from Eastern Europe to Central Asia.
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 Asia Minor ground squirrel, also known as Anatolian souslik, Anatolian ground squirrel, is a species of rodent in the family Sciuridae. It is found in Armenia, Iran, and Turkey. The scientific name roughly translates as "seed-lover with yellow underparts".
The Tian Shan ground squirrel is a species of squirrel found in the grasslands of western China, Kazakhstan, and Kyrgyzstan. A close relative of Spermophilus relictus, it was formerly considered the same species. It was formerly known as Spermophilus ralli, but that name is now known to be a synonym of S. relictus.
Spermophilus brevicauda is a species of rodent in the family Sciuridae. It is found in eastern Kazakhstan and the northern half of the Xinjiang region of China.
