Onychomys leucogaster
| Northern Grasshopper Mouse
(Onychomys leucogaster) | |
|---|---|
| Range | |
 | |
| Taxonomic classification | |
| Order: | Rodentia |
| Suborder: | Supramyomorpha |
| Infraorder: | Myomorphi |
| Superfamily: | Muroidea |
| Family: | Cricetidae |
| Subfamily: | Neotominae |
| Tribe: | Onychomyini |
| Genus: | Onychomys |
| Binomial details | |
| Onychomys leucogaster (zu Wied-Neuwied, 1841) | |
| Other resources | |
| Full taxonomic details at MDD | |
The Northern Grasshopper Mouse (Onychomys leucogaster) inhabits xeric grasslands and scrublands. At night it may be heard “howling”, making a high-pitched, piercing, pure tone call that is audible to humans 100 m away on a still night. It is similar in appearance to a deer mouse except for its very short tail.
Description
From McCarty (1975): "Onychomys leucogaster has a bicolored pelage. The short, thick tail tapers to an obtuse point and the tip is often white. Total length is 119 to 190 mm; tail length 29 to 62 mm: length of hind foot 17 to 25 mm; length of ear 12.4 to 16.9 m."
From Hoffmeister (1986): “A relatively short-tailed, long-bodied species; in adults the tail length (often about 44 mm) is usually less than half the length of the head-body (often 52 mm), size large, maxilllary tooth-row long (4.69 mm to 5.30 mm), skull long and broad across zygomatic arches, M3 usually longer than wide and semicircular or triangular in outline, M1 usually less than half the length of the maxillary tooth row, fur underparts with the basal band whitish or plumbeous in color.”
From Armstrong et al. (2010): "The northern grasshopper mouse is a stout-bodied, short-tailed mouse that superficially resembles a deer mouse. The dorsal coloration is gray in juveniles, molting to cinnamon-buff or reddish brown and becoming gray again in very old animals. The underparts and distal part of the tail are white."
Museum type specimens
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Holotype: USNM 266502. Onychomys leucogaster utahensis (aldousi). Adult male. Desert Range Experiment Station, Millard (Beaver) County, Utah. Collected 18 April 1941. -
Holotype: USNM 266502. Onychomys leucogaster utahensis (aldousi). Adult male. Desert Range Experiment Station, Millard (Beaver) County, Utah. Collected 18 April 1941. -
Holotype: USNM 263955. Onychomys leucogaster utahensis. Adult female. South end of Stansbury Island, Great Salt Lake, Tooele County, Utah. Collected 22 June 1938. -
Holotype: USNM 263955. Onychomys leucogaster utahensis. Adult female. South end of Stansbury Island, Great Salt Lake, Tooele County, Utah. Collected 22 June 1938. -
Holotype: USNM 19144/34872. Onychomys leucogaster breviauritus. Adult female. Fort Reno, Canadian County, Oklahoma. Collected 16 February 1890. -
Holotype: USNM 19144/34872. Onychomys leucogaster breviauritus. Adult female. Fort Reno, Canadian County, Oklahoma. Collected 16 February 1890. -
Holotype: USNM 202612. Onychomys leucogaster fuliginosus. Adult male. Lower end of Prospect Valley, Hualpai (Hualapai) Indian Reservation, Grand Canyon, Coconino County, Arizona. Collected 26 September 1913. -
Holotype: USNM 202612. Onychomys leucogaster fuliginosus. Adult male. Lower end of Prospect Valley, Hualpai (Hualapai) Indian Reservation, Grand Canyon, Coconino County, Arizona. Collected 26 September 1913.
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 Co., vic. of Willcox and Portal) | Hoffmeister (1986) | 145–161 (n=19) | 37–52 (n=19) | 21–23 (n=19) | 15–19 (n=19) | |
| Arizona (Coconino Co., lower end Prospect Valley) | Hoffmeister (1986) | 140–155 (n=7) | 42–48 (n=7) | 21–22 (n=7) | ||
| Arizona (Coconino Co., north of Page) | Hoffmeister (1986) | 139–160 (n=17) | 38–48 (n=17) | 21–22 (n=17) | 17–20 (n=17) | |
| Arizona (Coconino Co., south of Page) | Hoffmeister (1986) | 150–164 (n=12) | 41–48 (n=12) | 20–24 (n=12) | 18–20 (n=12) | |
| Arizona (Coconino Co., vic. of Wupatki, Cameron, Angell) | Hoffmeister (1986) | 138–161 (n=16) | 39–49 (n=16) | 21–23 (n=16) | 16–20 (n=16) | |
| Arizona (Mohave Co., northern part) | Hoffmeister (1986) | 142–155 (n=9) | 40–51 (n=9) | 21–22 (n=9) | 17–19 (n=9) | |
| California | Jameson & Peeters (2004) | 120–190 | 29–62 | 17–25 | 12–17 | 24–38 |
| Colorado | Armstrong et al. (2010) | 128–158 | 34–52 | 20–23 | 14–19 | 23–45 |
| Minnesota | Hazard (1982) | 139–166 | 34–45 | 19–23 | 14–18 | 34.8–50.6 |
| Nebraska | Johnsgard (2020) | 120–155 | 29–50 | 35–45 | ||
| North Dakota | Seabloom et al. (2020) | 157 | 43 | 22 | 14 | 42 |
| Texas | Schmidly & Bradley (2016) | 164 | 42 | 22 | 27–46, occasionally as much as 52 |
Skull
From Armstrong et al. (2010): "The skull is distinctly heavier than that of the deer mouse [Peromyscus maniculatus] but otherwise similar, although the third upper molar is reduced in size and the coronoid process of the mandible is as high or higher than the condyloid process; the latter character distinguishes the species from any other mouse in Colorado."
From Hoffmeister (1986) for members of the genus Onychomys: "skull presents a unique combination of characters including relatively broad braincase, weak zygomatic arches that flare far laterally, broad across anterior roots of the zygoma, and broad rostrum with wedge-shaped nasals; coronoid process of mandible ascends more dorsally than does condyloid process; cheek teeth with labial and lingual cusps about equal height, mesoloph always lacking in upper teeth, M3/3 peglike, transverse valleys extend entirely across cheek teeth..."
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Holotype: USNM 202612. Onychomys leucogaster fuliginosus. Adult male. Lower end of Prospect Valley, Hualpai (Hualapai) Indian Reservation, Grand Canyon, Coconino County, Arizona. Collected 26 September 1913. Dorsal view of the skull. Note that the zygomatic arches are broken and incomplete. -
Holotype: USNM 202612. Onychomys leucogaster fuliginosus. Adult male. Lower end of Prospect Valley, Hualpai (Hualapai) Indian Reservation, Grand Canyon, Coconino County, Arizona. Collected 26 September 1913. Ventral view of the skull. Note that the zygomatic arches are broken and incomplete. -
Holotype: USNM 202612. Onychomys leucogaster fuliginosus. Adult male. Lower end of Prospect Valley, Hualpai (Hualapai) Indian Reservation, Grand Canyon, Coconino County, Arizona. Collected 26 September 1913. Lateral view of the skull. Note that the zygomatic arch is incomplete. -
Holotype: USNM 202612. Onychomys leucogaster fuliginosus. Adult male. Lower end of Prospect Valley, Hualpai (Hualapai) Indian Reservation, Grand Canyon, Coconino County, Arizona. Collected 26 September 1913. Dorsal view of the mandible. -
Holotype: USNM 17997/24908. Onychomys leucogaster fuliginosus. Adult female. Black Tank lava beds, northeast of San Francisco Mountain, Coconino County, Arizona. Collected 27 September 1889. Lateral view of the left mandible. -
Holotype: USNM 17997/24908. Onychomys leucogaster fuliginosus. Adult. Upper molars. -
Holotype: USNM 17997/24908. Onychomys leucogaster fuliginosus. Adult. Lower molars.
Calls
From Hoffmeister (1986): "A number of sonic and ultrasonic calls are given by these mice. Commonly, they rear up on their hind legs, using the tail as support, pointing the head upwards, and opening the mouth. Sometimes the calls are made with all four feet on the ground."
The following call was provided by the Pasch Lab at the University of Arizona. For details regarding vocal production and vocal divergence in grasshopper mice, see Campbell et al. (2019).
Similar species
Comparison with Onychomys torridus
1. Total length 130 to 190 mm; tail usually less than half of body length (31 to 57%); maxillary toothrow long (3.8 to 4.8 mm); length of mandible usually more than 14 mm... Onychomys leucogaster. 2. Total length 120 to 163 mm; tail usually more than half of body length (48 to 56%); maxillary toothrow short (3.3 to 4.0 mm); length of mandible usually less than 14 mm...... Onychomys torridus.
From McCarty (1975): "O. torridus differs from O. leucogaster as noted in the key above, and as follows: mandible shorter (12.5 to 14.6 mm and 13.7 to 17.3 mm, respectively), zygomatic breadth narrower (11.9 to 13.7 mm and 12.6 to 17.3 mm, respectively), and smaller braincase (11.0 to 12.3 mm and 11.9 to 13.7 mm in width, respectively."
From Hoffmeister (1986): “O. leucogaster differs from O. torridus in numerous features, all of which are not obvious without careful examination and need to be used in combination. These include: tail less than half the body length, toothrow long, length of M1 usually less than half of the entire toothrow, M3 longer than wide, skull longer and wider (if condylobasal or greatest length is plotted against breadth, there is little or no overlap), baculum longer and bladelike rather than short and thin. If the fur on the underparts is white to the base, the animal is O. leucogaster, although some specimens do have the fur plumbeous as the base as in O. torridus.
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Northern Grasshopper Mouse (Onychomys leucogaster) -
Southern Grasshopper Mouse (Onychomys torridus) -
Northern Grasshopper Mouse (Onychomys leucogaster) -
Southern Grasshopper Mouse (Onychomys torridus)
Comparison with species in the genus Peromyscus
Onychomys is most easily confused with Peromyscus, from which it differs in having a short, thick tail that tapers to an obtuse point and the tip is often white, skull relatively broad across rostral region and braincase with a short rostrum and widely-flared but weak zygomatic arches; coronoid process of mandible ascends above rather than below level of condyloid process (Hoffmeister, 1986).
References
Armstrong DM, Fitzgerald JP, Meaney CA. 2010. Mammals of Colorado, Second Edition. Denver (CO, USA): University Press of Colorado.
Campbell P, Arévalo L, Martin H, Chen C, Sun S, Rowe AH, Webster MS, Searle JB, Pasch B. 2019. Vocal divergence is concordant with genomic evidence for strong reproductive isolation in grasshopper mice (Onychomys). Ecology and Evolution (9):12886-12896. https://doi.org/10.1002/ece3.5770
Hazard EB. 1982. The mammals of Minnesota. Minneapolis (MN, USA): University of Minnesota Press.
McCarty R. 1975. Onychomys torridus. Mammalian Species (59): 1-5.
Hoffmeister DF. 1986. Mammals of Arizona. Tucson (AZ, USA): University of Arizona Press.
Jameson EW, Peeters HJ. 2004. Mammals of California (No. 66). Berkeley (CA, USA): University of California Press.
Johnsgard PA. 2020. Wildlife of Nebraska: a natural history. Lincoln (NE, USA): University of Nebraska Press.
Seabloom R, Hoganson JW, Jensen WF. 2020. The mammals of North Dakota. Fargo (ND, USA): North Dakota State University Press.
Schmidly DJ, Bradley RD. 2016. The mammals of Texas. Austin (TX, USA): University of Texas Press.