After McKenna & Bell, 1997

    Spermophilus F. Cuvier, 1825
        Citellus Oken, 1816
        Spermatophilus Wagler, 1830
        Mamspermophilus Herrera, 1899
      including:
        Citillus Lichtenstein, 1827
        Otospermophilus Brandt, 1844
        Otocolobus Brandt, 1844, non Felis (Otocolobus) Brandt, 1841, a subgenus of cats
        Colobotis Brandt, 1844
        Colobates Milne-Edwards, 1874 [objective synonym of Colobotis Brandt, 1844]
        Ictidomys Allen, 1877
        Xerospermophilus Merriam, 1892
        Callospermophilus Merriam, 1897
        Ictidomoides Mearns, 1907
        Urocitellus Obolensky, 1927
        Poliocitellus H. Howell, 1938
        Notocitellus A.H. Howell, 1938
        †Pliocitellus Hibbard, 1942

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