Microtus mogollonensis

Mogollon Vole
(*Microtus mogollonensis*)
Mogollon Vole (Microtus mogollonensis)
Range
Taxonomic classification
Order:	Rodentia
Suborder:	Supramyomorpha
Infraorder:	Myomorphi
Superfamily:	Muroidea
Family:	Cricetidae
Subfamily:	Arvicolinae
Tribe:	Arvicolini
Genus:	Microtus
Subgenus:	Mynomes
Binomial details
	Microtus mogollonensis (Mearns, 1890)
Other resources
	Full taxonomic details at MDD

The Mogollon Vole (Microtus mogollonensis) is a small, brown vole found in montane meadows and shrublands.

Description

From Armstrong et al. (2010): "This is a small short-tailed vole with the tail less than 30 percent of the length of the head and body, usually less than 35 mm. The dorsal pelage is typically dark brown with the venter a buffy to ochraceous gray. The length of the hindfoot is usually less than 20 mm."

Museum type specimens

Holotype: AMNH MO-1403, AMNH MS-2351. Microtus mogollensis. Male. Baker's Butte, Mogollon Mountains, Coconino County, Arizona. Collected 26 July 1887. Dorsal view.
Holotype: AMNH MO-1403, AMNH MS-2351. Microtus mogollensis. Male. Baker's Butte, Mogollon Mountains, Coconino County, Arizona. Collected 26 July 1887. Ventral view.

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 (central Mogollon Plateau)	Hoffmeister (1986)	122–147 (n=16)	20–30 (n=16)	16–19 (n=16)
Arizona (Escudilla Mtn.)	Hoffmeister (1986)	122–153 (n=45)	22–33 (n=45)	17–20 (n=45)
Arizona (Hualapai Mtns.)	Hoffmeister (1986)	137.2 (n=5)	30.2 (n=5)	19.6 (n=5)
Arizona (south rim Grand Canyon)	Hoffmeister (1986)	123–140 (n=30)	22–31 (n=30)	16–20 (n=30)
Arizona (vicinity of Flagstaff, Coconino Co.)	Hoffmeister (1986)	115–149 (n=29)	20–32 (n=29)	16–19 (n=29)
Arizona (vicinity of Williams, Coconino Co.)	Hoffmeister (1986)	120–145 (n=40)	20–30 (n=40)	17–20 (n=40)
Colorado	Armstrong et al. (2010)	122–154	20–34	16–21	13–16	28–32
Texas	Schmidly & Bradley (2016)	141	32	21		29–48

Skull

From Armstrong et al. (2010): "The skull is short and broad with the zygomatic breadth usually greater than 60 percent of the condylobasal length. The last upper molar has 5 dentine lakes, ...the second upper molar has only 4 dentine lakes with no posterior accessory loop... incisive foramina broad and rounded posteriorly rather than narrow or abruptly constricted posteriorly... jugal bone of the zygomatic arch is expanded and the posterior margin of the palate is notched or grooved."

MSB:Mamm:164251. Lateral view of the skull of Microtus mogollensis.
MSB:Mamm:164170. Dorsal view of the skull of Microtus mogollensis.
MSB:Mamm:164170. Ventral view of the skull of Microtus mogollensis.
MSB:Mamm:164170. Lower jaw of Microtus mogollensis.
MSB:Mamm:164170. Upper incisors of Microtus mogollensis.
MSB:Mamm:164251. Upper molars of Microtus mogollensis
MSB:Mamm:164251. Lower molars of Microtus mogollensis.

Similar species

From Armstrong et al. (2010): "These animals can be easily confused with Phenacomys intermedius or M. montanus unless the skull is examined carefully."

Comparison with Microtus drummondii

In Microtus mogollonensis the second upper molar has only 4 dentine lakes with no posterior accessory loop, whereas in the Western Meadow Vole (Microtus drummondii) the second upper molar has four dentine lakes with a posterior accessory loop (Armstrong et al., 2010).

Western Meadow Vole (Microtus drummondii)
NEON06JK0. Western Meadow Vole (Microtus drummondii). Upper molars. Black arrows point to the three closed triangles on the second upper molar (M2). The purple arrow points to the usually rounded, closed lingual posterior loop on the M2, which is found only in Microtus drummondii and Microtus pennsylvanicus.

Comparison with Microtus montanus

From Armstrong et al. (2010): "M. mogollonensis differs from M. montanus in having incisive foramina broad and rounded posteriorly rather than narrow or abruptly constricted posteriorly. The jugal bone of the zygomatic arch is expanded and the posterior margin of the palate is notched or grooved."

Ventral view of the skull of Microtus mogollonensis. The incisive foramina, which is broad and rounded, is the opening of the incisive canals on the hard palate immediately behind the incisor teeth.
Ventral view of the skull of the Montane Vole (Microtus montanus). The incisive foramina, which is narrow and constricts abruptly, is the opening of the incisive canals on the hard palate immediately behind the incisor teeth.
Lateral view of the skull of Microtus mogollonensis showing the jugal bone of the zygomatic arch, which is expanded.
Lateral view of the skull of the Montane Vole (Microtus montanus) showing the jugal bone of the zygomatic arch, which is not expanded.

Comparison with Phenacomys intermedius

Superficially the Western Heather Vole (Phenacomys intermedius) may resemble the Microtus mogollonensis, from which is can be separated by the rooted cheekteeth with their deep inner reentrant angles.

Upper molars of Microtus mogollensis
Upper molars of Phenacomys intermedius.
Lower molars of Microtus mogollensis.
Lower molars of Phenacomys intermedius. Yellow arrow points to one of the many lingual re-entrant angles of lower cheek teeth, which are disproportionately large (more than halfway through the tooth; Naughton, 2012). The first lower molar (m1) has a variable number of closed triangles (3-7; Naughton, 2014). Black arrows point to the 5 closed triangles on the first lower molar (m1) in this individual.

References

Armstrong DM, Fitzgerald JP, Meaney CA. 2010. Mammals of Colorado, Second Edition. Denver (CO, USA): University Press of Colorado.

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

Jackson DJ, Cook JA. 2020. A precarious future for distinctive peripheral populations of meadow voles (Microtus pennsylvanicus). Journal of Mammalogy 101(1):36-51.

Mearns EA. 1890-02-21. Description of supposed new species and subspecies of mammals, from Arizona. Bulletin of the American Museum of Natural History 2(20):277-307.

Schmidly DJ, Bradley RD. 2016. The mammals of Texas. Austin (TX, USA): University of Texas Press.