Spermophile Ground Squirrels—Spermophile Ground Squirrels // Callospermophilus lateralis—Golden-mantled Ground Squirrel // Ictidomys/Xerospermophilus)—Ictidomys or Xerospermophilus Ground Squirrel // Ictidomys tridecemlineatus—Thirteen-lined Ground Squirrel // Otospermophilus bensoni—Benson Rock Squirrel // Otospermophilus variegatus—Rock Squirrel // "Spermophilus" cochisei—Cochise Ground Squirrel // Urocitellus elegans—Wyoming Ground Squirrel // Xerospermophilus spilosoma—Spotted Ground Squirrel
Synonyms. Spermophilus tridecemlineatus.
Although basically a Great Plains species, I. tridecemlineatus is scattered through New Mexico, being relatively common in the northeastern shortgrass plains. Otherwise, it occurs mostly in relictual grasslands in foothills and valleys of the southern mountains (Findley et al. 1975). It is not recorded from Trans-Pecos Texas (Schmidly 2004).
Tebedge (1988) records the presence of this small ground squirrel and compared it with I. mexicanus, which he noted has morphologically similar dentition, but is much larger. He does not mention, however, another local ground squirrel, Xerospermophilus spilosoma, that has similar dentition and is close in size to I. tridecemlineatus. Nonetheless, I. tridecemlineatus is expectable in the Pleistocene of southeastern New Mexico.
Earlier reports of occurrences in the Dry Cave sites (Animal Fair, Bison Chamber, and Harris' Pocket) are of specimens not clearly assignable between this species and Xerospermophilus spilosoma and are listed as "cf." pending further study.
Fig. 1. Thirteen-lined Ground Squirrel. Photo used under Creative Commons from Scorpions and Centaurs.
Medial Irvingtonian: SAM Cave (Rogers et al. 2000).
Mid/Late Wisconsin: Dark Canyon Cave (Tebedge 1988).
Late Wisconsin: Animal Fair 18-20 ka (Harris 1989; UTEP cf.); Balcony Room (UTEP cf.); Bison Chamber (Harris 1970; UTEP cf.); Dust Cave (Harris and Hearst 2012); Harris' Pocket (Harris 1970a; UTEP cf.); Hueco Mountains (Van Devender et al. 1987: cf.); Navar Ranch (Van Devender et al. 1987: cf.).
Late Wisconsin/Holocene: SAM Cave (Rogers et al. 2000).
Literature. Findley et al. 1975; Harris 1970a, 1989; Harris and Hearst 2012; Rogers et al. 2000; Schmidley 2004; Tebedge 1988; Van Devender et al. 1987.
Last Update: 6 Mar 2013