Zapus luteus

Southern Meadow Jumping Mouse
(*Zapus luteus*)
Southern Meadow Jumping Mouse (Zapus luteus)
Range
Taxonomic classification
Order:	Rodentia
Suborder:	Supramyomorpha
Infraorder:	Myomorphi
Superfamily:	Dipodoidea
Family:	Zapodidae
Genus:	Zapus
Binomial details
	Zapus luteus G. S. Miller, 1911
Other resources
	Full taxonomic details at MDD

Genetic analyses by Malaney et al. (2017) revealed that the subspecies Zapus hudsonius pallidus is closely related to the subspecies Zapus princeps luteus and that together they are more related to each other than to other subspecies in Z. hudsonius and Z. princeps. As a result, Malaney et al. (2017) proposed moving both subspecies to Zapus luteus. Southwestern populations represent a distinctive subspecies, Zapus luteus luteus, and jumping mice from the southern Great Plains represent subspecies Zapus luteus pallidus. The work of Malaney et al. (2017) has importantly exposed cryptic diversity and putative new species within Zapus. Further studies will be needed to fully understand new species boundaries and morphological variation.

Description

A formal species description for this taxon as delineated by Malaney et al. (2017) does not currently exist. The following descriptions from Krutzsch (1954) are provided for subspecies that Malaney et al. (2017) subsumed under this taxon.

From Krutzsch (1954) for the southwestern portion of the range (formerly of Zapus princeps luteus): "Size, small; back near Ochraceous-Buff, having black hair interspersed; mid-dorsal band not always well marked; sides Ochraceous-Buff with fine admixture of black hair; lateral line blending with Ochraceous-Buff of sides, not distinct; ventral surface white to base of hairs, in some cases lightly suffused with color of sides; tail indistinctly bicolored, tan to grayish-white below and brown above; hind feet grayish-white above; ears brownish, narrowly edged with Ochraceous-Buff; skull small; antorbital foramina relatively large; interorbital region broad; inferior ramus of the zygomatic process of the maxillary broad, often with medial projection; incisive foramina narrow posteriorly becoming broadly rounded anteriorly; palatal bridge relatively long; pterygoid fossae narrow; zygomatic arches relatively robust; nasals tapering at each end."

From Krutzsch (1954) for the northeastern portion of the range (formerly of Zapus hudsonius pallidus): "Size small; back near Cinnamon-Buff with admixture of dark-tipped hair forming distinct, broad, dorsal band; sides bright Cinnamon-Buff with sparse mixture of dark-tipped hair; lateral line usually distinct, of clear Cinnamon-Buff; belly white, sometimes with suffusion of color of sides, tail bicolored, brownish to brownish-black above, grayish-white to yellowish-white below; ears dark, narrowly edged with color of sides; feet white to grayish-white above; mastoid region relatively narrow; maxillary tooth-row relatively short; zygomata relatively short; zygomatic arch relatively broad; interorbital region relatively broad; auditory bullae relatively small and narrow; lateral margins of nasals not constricted posteriorly."

From Frey (2007) for the southwestern portion of the range (formerly of Zapus hudsonius luteus): "Upperparts bright orangeish or dark blonde and lacking a prominent dark mid-dorsal band (i.e., back is only slightly darker than sides and colors merge gradually; ears lacking distinct white or light buffy border but may have an orangeish tan border."

Other museum specimens

Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909.

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, New Mexico	Frey (2007)	194–235 (n=47)	114–145 (n=47)	28–34 (n=47)	10–19 (n=47)	14.0–28.5 (n=47)
Nebraska	Johnsgard (2020)	180–220	115–136			12–22

Skull

Holotype: USNM 133601. Zapus luteus. Adult female. Espanola, Rio Arriba County, New Mexico. Collected 24 June 1904. Dorsal view of the skull.
Holotype: USNM 133601. Zapus luteus. Adult female. Espanola, Rio Arriba County, New Mexico. Collected 24 June 1904. Ventral view of the skull.
Holotype: USNM 133601. Zapus luteus. Adult female. Espanola, Rio Arriba County, New Mexico. Collected 24 June 1904. Lateral view of the skull.
Holotype: USNM 133601. Zapus luteus. Adult female. Espanola, Rio Arriba County, New Mexico. Collected 24 June 1904. Dorsal view of the mandible.
Holotype: USNM 133601. Zapus luteus. Adult female. Espanola, Rio Arriba County, New Mexico. Collected 24 June 1904. Lateral view of the left mandible.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909. Dorsal view of the skull.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909. Ventral view of the skull.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909. Lateral view of the skull.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909. Dorsal view of the mandible.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909. Lateral view of the mandible.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909. Upper molars.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909. Lower molars.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Arrows point to the paracone in the first upper molar (M1) and second upper molar (M2), which is isolated (not attached to the body of the tooth).

Taxonomic notes

Malaney et al. (2017) recognized 9 species within Zapus, elevating some of the subspecies within the genus to species status. Genetic analyses by Malaney et al. (2017) revealed that Zapus hudsonius pallidus is closely related to Zapus princeps luteus and that together they are more related to each other than to other members in either species. As a result, Malaney et al. (2017) proposed moving both subspecies to Zapus luteus. Southwestern populations represent a distinctive subspecies, Zapus luteus luteus, and jumping mice from the southern Great Plains represent subspecies Zapus luteus pallidus. The work of Malaney et al. (2017) has importantly exposed cryptic diversity and putative new species within Zapus. Further studies will be needed to fully understand new species boundaries and morphological variation.

Zapus hudsonius subspecies boundaries as defined by Krutzsch (1954).
Zapus princeps subspecies boundaries as defined by Krutzsch (1954).

Similar species

Comparison with Zapus hudsonius

Differentiating the Northern Meadow Jumping Mouse (Zapus hudsonius) and Zapus luteus in the field may not currently be possible using morphological characters, particularly for Zapus luteus pallidus (southern Great Plains subspecies). A formal taxonomic revision of Zapus luteus is needed and may identify suitable characters for differentiating these species.

Ranges of the Southern Meadow Jumping Mouse (Zapus luteus) and Northern Meadow Jumping Mouse (Zapus hudsonius). The extent of the area of sympatry is not shown.

Comparison with Zapus princeps

Where Zapus luteus is sympatric with the Southwestern Jumping Mouse (Zapus princeps), the two species may be differentiated based on color and the shape of the first and second upper molar. Zapus luteus luteus (southwestern portion of the species range) has an overall coloration that is orange, an indistinct dorsal stripe, and the ears lack a white fringe; whereas Z. princeps has olive-yellow sides, a distinct blackish dorsal stripe, and the ears have a prominent white fringe (Frey, 2008). In Zapus luteus the paracone in the first upper molar (M1) and second upper molar (M2) is isolated, while the paracone in the M1 and M2 is attached to the body of the tooth in the Southwestern Jumping Mouse (Zapus princeps) (Jones, 1981).

Borrowed from Frey (2008): "Skins of two Z. h. luteus (bottom) from near Mora, Mora County (NMMNH 1228, 1229), and two Z. p. princeps (top) from Coyote Creek, Mora County (NMMNH 4040, 4042). Note the prominent white ear fringe, distinct blackish dorsal strip, and olive-yellow sides in Z. p. princeps, and lack of an ear fringe, overall orange coloration and indistinct dorsal strip in Z. h. luteus.
Ranges of the Southern Meadow Jumping Mouse (Zapus luteus) and the Southwestern Jumping Mouse (Zapus princeps).
Southwestern populations of the Southern Meadow Jumping Mouse (Zapus luteus) have ears that lack a white fringe.
Southwestern Jumping Mouse (Zapus princeps) ears are dark and edged with white or yellowish-white.
Holotype: USNM 160731. Zapus luteus australis. Young adult female. Socorro, Socorro County, New Mexico. Collected 23 August 1909. Arrows point to the paracone in the M1 and M2, which is isolated.

References

Frey JK. 2007. Key to the rodents of New Mexico. Final report submitted to New Mexico Department of Game and Fish, Santa Fe, New Mexico.

Frey JK. 2008. Morphology and genetics of the New Mexico meadow jumping mouse (Zapus hudsonius luteus). Final Report submitted to New Mexico Department of Game and Fish, Santa Fe, New Mexico.

Johnsgard PA. 2020. Wildlife of Nebraska: a natural history. Lincoln (NE, USA): University of Nebraska Press.

Jones GS. 1981. The systematics and biology of the genus Zapus (Mammalia, Rodentia, Zapodidae)(Canada, United States) (Doctoral dissertation, Indiana State University).

Krutzsch PH. 1954. North American jumping mice (genus Zapus). Lawrence, KS, USA: University of Kansas. Link

Malaney JL, Demboski JR, Cook JA. 2017. Integrative species delimitation of the widespread North American jumping mice (Zapodinae). Molecular Phylogenetics and Evolution 114:137-152.

Miller Jr GS. 1911-12-23. A new jumping-mouse from New Mexico. Proceedings of the Biological Society of Washington 24:253-254.