A New Pocket Mouse (Genus Perognathus) from Kansas

Excerpt

In studying the kinds of mammals known from Kansas, I had occasion to examine a series of Perognathus flavus from the western part of the state. Comparisons of these specimens with topotypes of named subspecies revealed that the specimens from Kansas belong to a heretofore undescribed subspecies which ranges through western Nebraska, eastern Colorado, western Kansas, and western Oklahoma. This subspecies is named and described as follows.

Perognathus flavus bunkeri, new subspecies

Type.—Female, adult, skin and skull; No. 11716, Univ. Kansas Mus. Nat. Hist.; Conard Farm, 1 mi. E Coolidge, Hamilton County, Kansas; 1 July 1936; obtained by F. Parks and C. W. Hibbard, original No. 894 of Hibbard.

Diagnosis.—Size large (see measurements). Color light, upper parts between Pinkish Buff and Cinnamon-Buff (capitalized color terms after Ridgway, Color Standards and Color Nomenclature, Washington, D. C., 1912), sparsely mixed with black hairs; the effect at a distance of eight feet, is between Clay Color and Tawny-Olive; lateral line between Pinkish Buff and Cinnamon-Buff; postauricular spots near Pinkish Buff; small subauricular spots white; underparts white. Skull of medium size (see measurements); frontonasal and mastoidal regions much enlarged; interparietal transversely narrow.

Comparisons.—From topotypes of P. f. flavus from El Paso, El Paso County, Texas, P. f. bunkeri differs as follows: Averaging larger in all cranial measurements taken except in occipitonasal length, which is approximately the same, and in interparietal width, which is less; color more buffy, with fewer black hairs dorsally. From topotypes of P. f. piperi from 23 miles southwest of Newcastle, Weston County, Wyoming, P. f. bunkeri differs as follows: Smaller in frontonasal length, mastoidal breadth, and length of auditory bulla; color more buffy, with fewer black hairs dorsally. From topotypes of P. f. sanluisi from nine miles east of Center, Alamosa County, Colorado, P. f. bunkeri differs as follows: Averaging larger in all cranial measurements taken except interparietal width, which is smaller; color lighter and more buffy.

Remarks.—This is a brightly colored subspecies of Perognathus flavus, with less black dorsally than any adjacent one. The lateral line is well marked. Three young adult specimens taken from Wakeeney, Trego County, Kansas, are much brighter than other specimens from Kansas. The five specimens from Greeley, Weld County, Colorado, are much darker dorsally, like P. f. piperi, but are referable to P. f. bunkeri on the basis of cranial characters.

The name P. f. bunkeri is proposed in recognization of the continued attention which the late Charles Dean Bunker, Curator of Birds and Mammals of the University of Kansas Museum of Natural History, gave to building up the collection of mammals from Kansas. Acknowledgment is made of the assistance afforded me by a Research Assistantship with the Kansas Biological Survey.

Measurements.—Measurements of holotype and average of four adults (two males and two females) from the type locality are as follows: total length, 104, 105.2; length of tail, 44, 47.5; length of hind foot, 16, 16.7; length of ear, 7, 7.2; occipitonasal length, 20.6, 20.9; frontonasal length, 14.0, 13.9; mastoidal breadth, 12.1, 12.0; length of bulla, 8.0, 7.8; interorbital breadth, 4.5, 4.6; alveolar length of upper molariform tooth-row, 3.3, 3.1; interparietal width, 3.2, 3.2. All of the measurements listed above are available for each of the five specimens except that the occipitonasal length and frontonasal length are not available for the two males....