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Dipodomys agilis

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Agile Kangaroo Rat
(Dipodomys agilis)
Range
Taxonomic classification
Order:Rodentia
Suborder:Supramyomorpha
Infraorder:Castorimorphi
Superfamily:Geomyoidea
Family:Heteromyidae
Subfamily:Dipodomyinae
Genus:Dipodomys
Binomial details
Dipodomys agilis Gambel, 1849
Other resources
Full taxonomic details at MDD

The Agile Kangaroo Rat (Dipodomys agilis) frequents open microhabitats in chaparral and coastal sage-scrub in southern California.

Description

From Wilson et al. (2016): "Tail is 155 % of head-body length. This is a medium-sized kangaroo rat with large ears, five toes on hindfeet (including small claw on side of hindfoot), and narrow skull. Upper parts are dark reddish brown or dusky cinnamon buff; tail is bicolored, with dull brownish-black crest and tuft. Juveniles have a darker pelage than adults and lack elongated crests of hairs on their tails."

Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891.
Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891.

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
California Jameson & Peeters (2004) 265–319 155–197 40–46 67–76
California Wilson et al. (2016) head and body: 115–125 (males); 107–113 (females) 170–195 (males); 170–192 (females) 40–46 13–15 66–79 (males); 63–78 (females)


Skull

The American Society of Mammalogists' Mammal Diversity Database (2026) reports the the holotype for the species was lost. The holotype for the subspecies perplexus is shown below.

  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891. Dorsal view of the skull.
  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891. Ventral view of the skull.
  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891. Lateral view of the skull.
  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891. Dorsal view of the mandible.
  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891. Lateral view of the mandible. The lower incisors are completely worn.
  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult. Upper molars.
  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult. Lower molars.

Taxonomy and distribution notes

Based on chromosomal, allozymic, morphologic, and ecologic differences between two chromosomal forms of Dipodomys agilis, Sullivan & Best (1997) recommended that the 2n = 62 chromosomal form be referred to as the Agile Kangaroo Rat (Dipodomys agilis) and the southern 2n = 60 chromosomal form be given specific status as the Dulzura Kangaroo Rat (Dipodomys simulans).

From Cui and Nunney (2025), summarizing the results of their genomic analysis of the Agile Kangaroo Rat (AKR, Dipodomys agilis) and the Dulzura Kangaroo Rat (Dipodomys simulans) (DKR); "In summary, genomic analysis provided evidence of the long term genetic separation of AKR and DKR, supporting the original division of these two taxa into two species by Sullivan and Best (1997) based primarily on their karyotype difference. Given the finding that AKR and DKR are genetically distinct, with no evidence of a history of genetic introgression, both taxa satisfy the criterion of the genetic species concept, where a species is a group of genetically compatible interbreeding natural populations that is genetically isolated from other such groups (Baker and Bradley 2006). There was also no evidence of the sympatry that had been inferred from small morphological differences in samples collected south of the mountains by Sullivan and Best (1997). Of course, this genomic evidence has no bearing on whether or not these two species have developed pre- or post-mating reproductive isolating mechanisms, only that there is no evidence of genetic mixing since the two taxa split. Similarly, the possibility of historical sympatry is not excluded (although the absence of any indication of genetic introgression makes this unlikely), but instead it is suggested that the ecological shift at the southern edge of the mountains [San Gabriel and San Bernardino Mountains] probably maintains their separation despite the absence of a clear physical barrier preventing sympatry."

Habitat

From Price et al. (1991): "Frequents open microhabitats in chaparral and coastal sage-scrub vegetation (Keeley and Keeley, 1988; M'Closkey, 1976; Meserve, 1976; Price and Kramer, 1984) and increases in abundance following wildfires that create open space (Price and Waser, 1984)."

Similar species

Comparison with Dipodomys heermanni, D. simulans and D. venustus

From Wilson et al. (2016): "The Agile Kangaroo Rat is most similar to the Dulzura Kangaroo Rat (D. simulans) that is smaller with smaller ears and narrower face; the Narrow-faced Kangaroo Rat (D. venustus) that is larger with longer ears and narrower face; and Heermann’s Kangaroo Rat (D. heermanni) that is larger with smaller ears and wider face." From Sullivan & Best (1997): "Several characters reliably separate D. agilis from D. simulans, including larger size, narrower skull, and more oval-shaped auditory bullae of D. agilis as viewed from above."

  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891.
  • USNM 127158. Heermann's Kangaroo Rat (Dipodomys heermanni). Adult female. Tulare County, California. Collected 23 June 1903.
  • Holotype: USNM 33105/45103. Dulzura Kangaroo Rat (Dipodomys simulans). Adult female. Dulzura, San Diego County, California. Collected 24 November 1891.
  • Holotype: USNM 51852. Narrow-faced Kangaroo Rat (Dipodomys venustus). Adult male. Santa Cruz, Santa Cruz County, California. Collected 12 March 1893.
  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Dorsal view of the skull.
  • USNM 127158. Heermann's Kangaroo Rat (Dipodomys heermanni). Adult female. Tulare County, California. Collected 23 June 1903. Dorsal view of the skull.
  • Holotype: USNM 33105/45103. Dulzura Kangaroo Rat (Dipodomys simulans). Dorsal view of the skull.
  • Holotype: USNM 51852. Narrow-faced Kangaroo Rat (Dipodomys venustus). Adult male. Santa Cruz, Santa Cruz County, California. Collected 12 March 1893. Dorsal view of the skull.

Comparison with Dipodomys nitratoides

The San Joaquin Kangaroo Rat (Dipodomys nitratoides) differs from Dipodomys agilis in smaller size and having four hind toes instead of five.

  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891.
  • Holotype: USNM 54674. San Joaquin Kangaroo Rat (Dipodomys nitratoides). Adult male. Tipton, San Joaquin Valley, Tulare County, California. Collected 25 June 1893.
  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Dorsal view of the skull.
  • USNM 34843/43823. San Joaquin Kangaroo Rat (Dipodomys nitratoides). Young adult male. Fresno, San Joaquin Valley, Fresno County, California. Collected 23 September 1891. Dorsal view of the skull.

Comparison with Dipodomys stephensi

From Bleich (1977): "[Dipodomys] stephensi is similar externally to D. agilis, the geographic distribution of which partly coincides with that of stephensi. D. stephensi differs from agilis in having: a relatively wider head; broader arietiform markings; dusky rather than dark soles on the hind feet; few rather than many white hairs in the tail tuft; many hairs in the dorsal and ventral tail stripes having white bases (giving the stripes a grizzled appearance); narrow lateral white tail stripes indistinctly demarcated from the dark stripes, rather than broad, sharply demarcated lateral stripes; ear averaging 15 mm rather than 17 mm in length."

  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Adult male. Walker Basin, Kern County, California. Collected 15 July 1891.
  • Holotype: USNM 186503. Stephens's Kangaroo Rat (Dipodomys stephensi). Adult male. San Jacinto Valley, Riverside County, California. Collected 27 November 1885.
  • Holotype: USNM 29261/41328. Dipodomys agilis perplexus. Dorsal view of the skull.
  • Holotype: USNM 186503. Stephens's Kangaroo Rat (Dipodomys stephensi). Adult male. San Jacinto Valley, Riverside County, California. Collected 27 November 1885. Dorsal view of the skull. The right zygomatic arch and tip of the right nasal bone are broken and missing.
Species Toes Tail_tip Size
Dipodomys agilis 5 dusky medium to large
Dipodomys heermanni 5 dusky medium to large
Dipodomys nitratoides 4 dusky small
Dipodomys simulans 5 dusky medium
Dipodomys stephensi 5 dusky, sometimes tip appears pale medium
Dipodomys venustus 5 dusky large

References

Baker RJ, Bradley RD. 2006. Speciation in mammals and the genetic species concept. Journal of Mammalogy 87:643–662.

Bleich VC. 1977. Dipodomys stephensi. Mammalian Species (73): 1-3.

Cui Y, Nunney L. 2025. Genomic analysis of differentiation and demography of the formerly conspecific agile (Dipodomys agilis) and Dulzura (D. simulans) kangaroo rats. Heredity, pp.1-10. https://doi.org/10.1038/s41437-025-00789-3

Gambel W. 1849-03-31. Descriptions of two new California quadrupeds. Proceedings of the Academy of Natural Sciences of Philadelphia 4(4):77-78.

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

Keeley JE, Keeley SC. 1988. Chaparral, p. 165-208. In: M. G. Barbour and W. D. Billings (eds.). North American terrestrial vegetation. Cambridge University Press, Cambridge.

Mammal Diversity Database. 2026. Dipodomys agilis (ASM Mammal Diversity Database #1001889) fetched May 31, 2026. https://mammaldiversity.org/taxon/1001889

Meserve PL. 1976. Habitat and resource utilization by rodents of a California coastal sage scrub community. Journal of Animal Ecology (45):647-666.

M'Closkey RT. 1976. Community structure in sympatric rodents. Ecology (57):728-739.

Price MV, Kramer KA. 1984. On measuring microhabitat affinities with special reference to small mammals. Oikos (42):349-354.

Price MV, Longland WS, Goldingay RL. 1991. Niche relationships of Dipodomys agilis and D. stephensi: two sympatric kangaroo rats of similar size. American Midland Naturalist: 172-186.

Price MV, Waser NM. 1984. On the relative abundance of species: postfire changes in a coastal sage scrub rodent community. Ecology (65):1161-1169.

Sullivan RM, Best TL. 1997. Systematics and Morphologic Variation in Two Chromosomal Forms of the Agile Kangaroo Rat (Dipodomys agilus). Journal of Mammalogy 78(3): 775-797.

Wilson DE, Lacher, Jr TE, Mittermeier RA. 2016. Heteromyidae. In: Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I. Barcelona: Lynx Edicions: 170-233, ISBN: 978-84-941892-3-4, DOI: https://zenodo.org/records/6611160

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