Dipodomys ordii inaquosus [Hall], Proc. Biol. Soc. Washington, 54:58, May 20, 1941.
Type.—Male, adult, no. 73580, Museum of Vertebrate Zoology, University of California; 11 mi. E and 1 mi. N Jungo, 4,200 ft., Humboldt County, Nevada; obtained on July 26, 1936, by Ward C. Russell, original no. 5026.
Range.—Southeastern Humboldt and northern Lander counties, Nevada; marginal occurrences, all in Nevada, are: 7 mi. N Winnemucca, 8 mi. E and 1 mi. N Jungo, 15 mi. SW Winnemucca, 23 mi. NW Battle Mountain, Izenhood, and 18 mi. NE Iron Point.
Diagnosis.—Size medium (see measurements). Color pale, entire dorsal surface Pinkish Buff, purest on sides and flanks with but slight suffusion of black on the upper parts; cheeks white; arietiform marks indistinct, pinnae of ears, plantar surfaces of hind feet, dorsal and ventral stripes of tail, brownish. Skull medium in size; rostrum short and wide; nasals relatively long and expanded distally; braincase but slightly vaulted; interorbital width narrow; extension of premaxillae posterior to nasals relatively great; interparietal relatively large; pterygoid fossae subcircular; foramen magnum ovoid; auditory bullae relatively greatly expanded ventrally.
Comparisons.—From Dipodomys ordii columbianus, D. o. inaquosus differs as follows: Size larger; color lighter; skull larger; nasals longer; rostrum longer and wider; interorbital region narrower; braincase more vaulted; interparietal larger; auditory bullae more inflated ventrally; pterygoid fossae subcircular as opposed to nearly circular; zygomatic arches more robust.
From Dipodomys ordii monoensis, D. o. inaquosus differs in: Size larger; color lighter; skull larger; nasals longer; rostrum wider; interorbital width greater; braincase more vaulted; auditory bullae more inflated laterally, ventrally and posteriorly; interparietal region narrower; pterygoid fossae subcircular as opposed to circular; lacrimal processes larger; foramen magnum ovoid as opposed to circular.
Remarks.—In pallor D. o. inaquosus closely approaches Dipodomys ordii celeripes from eastern Nevada and western Utah. The two populations are separated, however, by a large area inhabited by the darker Dipodomys ordii columbianus. Specimens from 18 mi. NE Iron Point, Nevada, which [Hall] (1946:413) refers to D. o. columbianus, are intergrades in color, size and cranial characters and here are referred to D. o. inaquosus instead of to D. o. columbianus. Animals from Toulon are intergrades between D. o. inaquosus and Dipodomys ordii monoensis but are referable to the latter.
Specimens examined.—Total, 47, all from Nevada, distributed as follows: Humboldt County: 18 mi. NE Iron Point, 4600 ft., 1 (MVZ); 7 mi. N Winnemucca, 4400 ft., 4 (MVZ); 1 mi. N Winnemucca, 4600 ft., 8 (MVZ); 5 mi. NE Golconda, 7 (MVZ); 3 mi. SW Winnemucca, 4500 ft., 1 (MVZ); 4 mi. SW Winnemucca, 4500 ft., 1 (MVZ); 5 mi. SW Winnemucca, 4600 ft., 2 (MVZ); 8 mi. E and 1 mi. N Jungo, 4200 ft., 6 (MVZ); 11 mi. E and 1 mi. N Jungo, 4200 ft., 7 (MVZ); 10 mi. SW Winnemucca, 4500 ft., 1 (MVZ); 23 mi. NW Battle Mountain, 4 (MVZ). Pershing County: 15 mi. SW Winnemucca, 1 (MVZ). Lander County: Izenhood, 2 (MVZ); 3 mi. S Izenhood, 2 (MVZ).