Class [Mammalia] Linnaeus, 1758 - mammals
   Order Rodentia Bowdich, 1821 - rodents
     Family Sciuridae Batsch, 1788 - squirrels, chipmunks, marmots, and prairie dogs
       Subfamily Sciurinae Batsch, 1788 - tree and ground squirrels
         Genus Spermophilus Cuvier, 1825 - ground squirrels
           Spermophilus adocetus Merriam, 1903 - tropical ground squirrel
           Spermophilus alaschanicus - Alashan ground squirrel see Spermophilus alashanicus Büchner, 1888
           Spermophilus annulatus Audubon & Bachman, 1842 - ring-tailed ground squirrel
           Spermophilus armatus Kennicott, 1863 - Uinta ground squirrel
           Spermophilus atricapillus W. Bryant, 1889 - Baja California rock squirrel
           Spermophilus beecheyi (Richardson, 1829) - California ground squirrel
           Spermophilus beldingi Merriam, 1888 - Belding's ground squirrel
           Spermophilus brunneus (A.H. Howell, 1928) - Idaho ground squirrel
           Spermophilus citellus Linnaeus, 1766 - European souslik
           Spermophilus columbianus (Ord, 1815) - Columbian ground squirrel
           Spermophilus dauricus Brandt, 1843 - Daurian ground squirrel
           Spermophilus elegans Kennicott, 1863 - Wyoming ground squirrel
           Spermophilus erythrogenys Brandt, 1841
           Spermophilus franklinii (Sabine, 1822) - Franklin's ground squirrel
           Spermophilus fulvus Lichtenstein, 1823 - large-toothed souslik
           Spermophilus madrensis Merriam, 1901 - Sierra Madre ground squirrel
           Spermophilus major Pallas, 1778 - russet souslik
           Spermophilus mexicanus (Erxleben, 1777) - Mexican ground squirrel
           Spermophilus mohavensis Merriam, 1889 - Mohave ground squirrel
           Spermophilus musicus Ménétries, 1832
           Spermophilus parryii (Richardson, 1825) - Arctic souslik
           Spermophilus perotensis Merriam, 1893 - Perote ground squirrel
           Spermophilus pygmaeus Pallas, 1778 - little souslik
           Spermophilus relictus Kashkarov, 1923 - Tien Shan souslik
           Spermophilus richardsoni - Richardson's ground squirrel see Spermophilus richardsonii (Sabine, 1822)
           Spermophilus saturatus (Rhoads, 1895) - Cascade golden-mantled ground squirrel
           Spermophilus spilosoma Bennett, 1833 - spotted ground squirrel
           Spermophilus suslicus Güldenstaedt, 1770 - spotted souslik
           Spermophilus tereticaudus Baird, 1858 - round-tailed ground squirrel
           Spermophilus townsendii Bachman, 1839 - Townsend's ground squirrel
           Spermophilus tridecemlineatus (Mitchill, 1821) - thirteen-lined ground squirrel
           Spermophilus undulatus Pallas, 1778 - long-tailed souslik
           Spermophilus variegatus (Erxleben, 1777) - rock squirrel
           Spermophilus washingtoni (A.H. Howell, 1938) - Washington ground squirrel
           Spermophilus xanthoprymnus Bennett, 1835
           Spermophilus lateralis (Say, 1823) - golden-mantled ground squirrel