Neotamias canipes
| Gray-footed Chipmunk
(Neotamias canipes) | |
|---|---|
| Range | |
 | |
| Taxonomic classification | |
| Order: | Rodentia |
| Suborder: | Sciuromorpha |
| Family: | Sciuridae |
| Subfamily: | Xerinae |
| Tribe: | Tamiini |
| Genus: | Neotamias |
| Binomial details | |
| Neotamias canipes (V. O. Bailey, 1902) | |
| Other resources | |
| Full taxonomic details at MDD | |
The Gray-footed Chipmunk (Neotamias canipes) is (primarily) a forest-dwelling chipmunk of southeastern New Mexico and western Texas.
Description
From Best et al. (1992): "a small, grayish-appearing squirrel, the upperparts marked with four whitish and five brownish stripes. The nape and shoulders usually have a wash of smoke gray. The dorsal stripes are black or brownish black. The inner pair of pale stripes is smoke gray, and the outer pair is grayish white (Davis, 1974). In summer pelage (August-September), the top of the head is mixed sayal brown and grayish white, bordered on each side with a stripe of fuscous black, shaded with sayal brown. The ocular stripe is black and is edged with sayal brown. The submalar stripe is sayal brown and shaded with fuscous. The ears are chaetura drab, broadly margined posteriorly with grayish white and washed on the anterior margin with sayal brown. Postauricular patches are pale smoke-gray. Shoulders, rump, and thighs have a wash of smoke gray, sprinkled with pinkish buff. The median dorsal stripe is broad, black, and bordered with sayal brown. The outer pair of dark stripes is fuscous black sprinkled with mikado brown or sayal brown. Lateral stripes are distinct and mikado brown. Sides are sayal brown or pale clay in color. The median pair of pale stripes is grayish white or pale smoke-gray. The outer pair of stripes is white. The tail above is fuscous black (the bases of hairs are pinkish cinnamon) overlaid with pinkish buff, tilleul buff, or pale smoke-gray. Hind feet are smokegray, faintly shadowed with pinkish buff. The tail beneath is ochraceous tawny, bordered with fuscous black and edged with pinkish buff, tilluel buff, or pale smoke gray. The underparts are creamy white. Winter pelage (May) is similar to summer pelage, but averages slightly more grayish above and paler on the sides (color nomenclature follows Ridgway, 1912—Howell, 1929)."
Museum images
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Holotype: USNM 109229. Neotamias canipes canipes. Adult female. Guadalupe Mountains, Culberson County, Texas. Collected 24 August 1901. -
Holotype: USNM 109229. Neotamias canipes canipes. Adult female. Guadalupe Mountains, Culberson County, Texas. Collected 24 August 1901. -
Holotype: USNM 109229. Neotamias canipes canipes. Adult female. Guadalupe Mountains, Culberson County, Texas. Collected 24 August 1901.
External measurements
Length measurements are in millimeters (mm) and weight measurements are in grams (g), unless stated otherwise. If available, the sample size (n=) is provided. If a range is not provided and n= is not given, then the listed measurement represents an average.
| Part of range | Reference | Total length | Tail length | Hindfoot length | Ear length | Mass |
|---|---|---|---|---|---|---|
| Texas | Schmidly & Bradley (2016) | 225 | 102 | 35 |
Skull
Greatest length of skull is 36-39 mm (Sutton, 1992).
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Holotype: USNM 109229. Neotamias canipes canipes. Adult female. Guadalupe Mountains, Culberson County, Texas. Collected 24 August 1901. Dorsal view of the skull. Note that the tip of the nasals are broken. -
Holotype: USNM 109229. Neotamias canipes canipes. Adult female. Guadalupe Mountains, Culberson County, Texas. Collected 24 August 1901. Ventral view of the skull. Note that the tip of the nasals are broken. -
Holotype: USNM 109229. Neotamias canipes canipes. Adult female. Guadalupe Mountains, Culberson County, Texas. Collected 24 August 1901. Lateral view of the skull. Note that the tip of the nasals are broken. -
Holotype: USNM 109229. Neotamias canipes canipes. Adult female. Guadalupe Mountains, Culberson County, Texas. Collected 24 August 1901. Dorsal view of the mandible. -
Holotype: USNM 109229. Neotamias canipes canipes. Adult female. Guadalupe Mountains, Culberson County, Texas. Collected 24 August 1901. Lateral view of the left mandible.
Similar species
From Best et al. (1992): "canipes is distinguished from other chipmunks by the gray dorsal surfaces of the hind feet (Findley et al., 1975). In southern New Mexico, quadrivittatus, cinereicollis, and canipes were considered conspecific until bacular and karyotypic differences were demonstrated (Fleharty, 1960; Patterson, 1980b, 1984b). Compared with minimus, canipes is larger, has a whitish upper lip, and has brownish lateral stripes (Findley et al., 1975). Compared with cinereicollis, the skull of canipes averages slightly larger (Howell, 1929). N. canipes does not possess solid black in the lateral dorsal stripes. These are mixed blackish and rusty in canpies, and the centers are solid black in cinereicollis (Stone and Rehn, 1903). In canipes, the outer pair of dorsal stripes is more brownish and the sides of the nose and face are less heavily washed with buff. Feet are more grayish, tail edgings paler and more grayish, and hind foot averages shorter (Howell, 1929). In fresh postbreeding pelage, canipes is grayer throughout, with paler and duller ochraceous on the sides. Tips of long hairs on the rump and upper surface of tail are white instead of yellowish. The feet are clear gray without a tinge of yellowish. The black dorsal stripe reaches forward to between the ears (Bailey, 1902). The skull of canipes averages larger, and has a relatively longer and more slender rostrum than that of quadrivittatus. The shoulders have a grayish wash (the same region is tawny in quadrivittatus). The ocular stripe is broader and more blackish and the head is darker and more grayish. The dark dorsal stripes average broader, the outer pairs are more brownish, and the feet are more grayish (Howell, 1929)." See Best et al. (1992) for differences in bacula and karyotype.
References
Best TL, Bartig JL, Burt SL. 1992. Tamias canipes. Mammalian Species (411):1-5. https://doi.org/10.2307/0.411.1
Findley JS, Harris AH, Wilson DE, Jones C. 1975. Mammals of New Mexico. Albuquerque (NM, USA): University of New Mexico Press.
Fleharty ED. 1960. The status of the gray-necked chipmunk in New Mexico. Journal of Mammalogy 41:235-242.
Howell AH. 1929. Revision of the American chipmunks (genera Tamias and Eutamias). North American Fauna 52:1-157.
Patterson BD. 1980b. A new subspecies of Eutamias quadrivittatus (Rodentia: Sciuridae) from the Organ Mountains, New Mexico. Journal of Mammalogy 61:455-464.
Patterson BD. 1984b. Geographic variation and taxonomy of Colorado and Hopi chipmunks (genus Eutamias). Journal of Mammalogy 65:442-456.
Stone W, Rehn JAG. 1903. On the terrestrial vertebrates of portions of southern New Mexico and western Texas. Proceedings of the Academy of Natural Sciences of Philadelphia 55:16-34.
Sutton DA. 1992. Tamias amoenus. Mammalian Species (390):1-8.