Dipodomys ordii pallidus [Durrant and Setzer]
Dipodomys ordii pallidus [Durrant and Setzer], Bull. Univ. Utah, 35 (no. 26):24, June 30, 1945.
Type.—Male, adult, no. 3526, Museum of Zoology, University of Utah; Old Lincoln Highway, 18 mi. SW Orr's Ranch in Skull Valley, 4,400 ft., Tooele County, Utah; obtained on June 6, 1940, by S. D. [Durrant], original no. 1905.
Range.—Low valleys of west-central Utah in Tooele, Juab and Millard counties; marginal occurrences are: all in Utah, 18 mi. SW Orr's Ranch, 7 mi. S Fish Springs, Hinckley and Lynndyl.
Diagnosis.—Size medium (see measurements). Color light, entire dorsal surface Light Pinkish Cinnamon, purest on sides and flanks, with but slight suffusion of black on upper parts; cheeks white; arietiform markings, pinnae of ears, plantar surfaces of hind feet, dorsal and ventral stripes of tail, brownish. Skull large; auditory bullae long, wide and well inflated; external auditory meatus elongate with a notch on the dorsal border; nasals long and flaring distally.
Comparisons.—From Dipodomys ordii celeripes, D. o. pallidus differs in: Size larger; color generally darker, although some specimens are lighter; skull larger; nasals longer and more flared distally; interorbital width greater; auditory bullae larger; external auditory meatus larger.
From Dipodomys ordii fetosus, D. o. pallidus differs in: Size larger; color lighter; ventral stripe of tail indistinct as opposed to pronounced; skull larger; nasals longer and more flared distally; auditory bullae larger; external auditory meatus larger; palate shorter and broader.
For comparisons with Dipodomys ordii marshalli and Dipodomys ordii utahensis see accounts of those subspecies.
Remarks.—Among named subspecies of Dipodomys ordii, D. o. pallidus most closely resembles, morphologically, D. a. marshalli, its nearest geographic neighbor to the north and east. Intergradation with Dipodomys ordii utahensis is noted in color and intermediacy of body size of specimens from Clover Creek. The majority of cranial characters, however, show these animals to be referable to D. o. utahensis rather than to D. o. pallidus. Specimens taken at Lynndyl and Hinckley show intergradation in size of body, length and configuration of the nasals and the degree of inflation of the auditory bullae between Dipodomys ordii celeripes and D. o. pallidus. The majority of characters studied show these latter animals to be referable to D. o. pallidus. Specimens from 35 and 60 miles west of Delta, in size of body and shape and inflation of the auditory bullae, are intermediate between D. o. pallidus and D. o. celeripes. These specimens are here referred to D. o. celeripes.