Chaetodipus baileyi

Bailey's Pocket Mouse (Chaetodipus baileyi)
Range
Taxonomic classification
Order:	Rodentia
Suborder:	Supramyomorpha
Infraorder:	Castorimorphi
Family:	Heteromyidae
Subfamily:	Perognathinae
Genus:	Chaetodipus
Binomial details
Chaetodipus baileyi (Merriam, 1894)
Other resources
Full taxonomic details at MDD

Riddle et al. (2000) examined phylogenetic relationships within Chaetodipus baileyi and concluded that populations west of the Colorado River and Sea of Cortez should be recognized as a distinct species, Chaetodipus rudinoris.

Description

From Hoffmeister (1986): "A large-sized (largest in Arizona) species of the subgenus Chaetodipus; tail long and well-haired; hind feet long; skull large."

From Paulson (1988): "The pelage above is grayish, washed to a varying degree with yellow, and is somewhat harsh; underparts are whitish."

From Patton and Alvarez-Castañeda (editors, 1999): "Chaetodipus baileyi is one of the largest species in the genus, with total length usually more than 200 [mm] and a hind foot usually greater than 26 [mm]. It lacks stiff rump spines, has a soft yellowish gray-brown dorsal pelage color and a self-colored white venter. The ears are moderately large, usually greater than 9 mm; the tail is long, strongly crested, and buff to gray above, whitish below."

Ears have a lobed antitragus.

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
Arizona (Cochise County, San Bernardino Ranch)	Hoffmeister (1986)	body length: 98.5 (males, n=16) and 92.0 (females, n=7)		males: 28.9 (n=16); females: 29.0 (n=7)
Arizona (Gila County, vicinity of Roosevelt)	Hoffmeister (1986)	body length: 99.7 (males, n=27) and 92.8 (females, n=18)		males: 28.31 (n=27); females: 27.69 (n=18)
Arizona (Pima County, Baboquivari Mts.)	Hoffmeister (1986)	body length: 94.9 (males, n=15) and 91.9 (females, n=13)		males: 29.7 (n=15); females: 27.8 (n=13)
Arizona (Pima County, vicinity of Arivaca)	Hoffmeister (1986)	body length: 99.9 (males, n=12) and 98.6 (females, n=11)		males: 28.14 (n=12); females: 26.9 (n=11)
Arizona (Pinal County, Superior, Hayden)	Hoffmeister (1986)	body length: 96.9 (males, n=28) and 92.88 (females, n=26)		males: 27.78 (n=28); females: 26.98 (n=26)
Arizona (Yuma County, Castle Dome, Harquahala, Kofa Mts.)	Hoffmeister (1986)	body length: 99.14 (males, n=7) and 95.42 (females, n=12)		males: 27.86 (n=7); females: 25.67 (n=12)
not reported	Ceballos (editor, 2014)	188–223	103–124	24–27	7–11	24–28

Skull

From Hoffmeister (1986): "interorbital region wider than width of interparietal; toothrow long (alveolar length of maxillary toothrow always 4.0 mm or more)."

Image(s) coming soon. We are currently imaging this character.

Similar species

From Patton and Alvarez-Castañeda (editors, 1999): "This species can readily be distinguished from all sympatric or near-sympatric chaetodipine pocket mice by the combination of its large size and lack of evident stiff rump spines. Confusion is really only possible between baileyi and C. penicillatus in Arizona and Sonora... but, again, baileyi is significantly larger in most dimensions of the body and skull."

Comparison with Chaetodipus hispidus

From Patton and Alvarez-Castañeda (editors, 1999): "It is nearly the same size as C. hispidus in southeastern Arizona, but differs by its long and crested tail and grayish, instead of yellowish brown dorsal coloration."

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  Chaetodipus baileyi

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  Chaetodipus hispidus

Comparison with Chaetodipus penicillatus

From Hoffmeister (1986): "penicillatus (large specimens) is sometimes confused with and difficult to distinguish from baileyi. C. penicillatus in general is smaller than C. baileyi, with smaller body, shorter hind feet, and smaller skulls." Hoffmeister (1986) noted that characters useful for distinguishing C. penicillatus from C. baileyi are: hind foot usually 26 mm or less in C. penicillatus, whereas the hind foot is usually 27 mm or more in males in C. baileyi; interorbital breadth less than interparietal breadth in C. penicillatus, whereas in C. baileyi the interorbital width usually equal to or greater than interparietal width; the depth of the skull is usually 9.65 mm or less in C. penicillatus, whereas in baileyi the depth of the skull is 10.2 mm or more; the distance across maxillary toothrow (measured from the outside of right M1 to outside left M1) usually 4.9 mm or less, whereas in C. baileyi the distance across maxillary toothrow is usually 5.0 mm or more.

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  Chaetodipus baileyi

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  Desert Pocket Mouse (Chaetodipus penicillatus)

References

Ceballos G, editor. 2014. Mammals of Mexico. Baltimore (MD, USA): Johns Hopkins University Press.

Hall ER. 1981. The mammals of North America. 2 vols. John Wiley and Sons, New York.

Hoffmeister DF. 1986. Mammals of Arizona. Tucson (AZ, USA): University of Arizona Press.

Ingles LG. 1947. Mammals of California and its coastal waters. Stanford (CA, USA): Stanford University Press.

Jameson EW, Peeters HJ. 2004. Mammals of California (No. 66). Berkeley (CA, USA): University of California Press.

Merriam CH. 1894. Descriptions of Eight New Pocket Mice (Genus Perognathus). Proceedings of the Academy of Natural Sciences of Philadelphia 46, 262.

Patton JL, Alvarez-Castañeda ST, editors. 1999. Family Heteromyidae. Mamiferos del noroeste de México. La Paz (Baja California Sur, MX): Centro de Investigaciones Biológicas del Noroeste.

Riddle BR, Hafner DJ, Alexander LF. 2000. Comparative phylogeography of Baileys' pocket mouse (Chaetodipus baileyi) and the Peromyscus eremicus species group: historical vicariance of the Baja California peninsular desert. Molecular Phylogenetics and Evolution 17(2): 161-172.