Mustela frenata pulchra Hall, Carnegie Instit. Washington Publ. 473:98, November 20, 1936.
Type.—Male, adult, skeleton and skin; no. 16668, Mus. Vert. Zoöl.; Buttonwillow, Kern County, California; April 30, 1912; obtained by J. Grinnell; original no. 1953.
The skull (plates [22]-[24]) is complete and unbroken (a fracture in the right jugal has healed). All teeth are present and entire. The skeleton lacks the os penis, left fibula, shaft of left tibia and the distal three or four caudal vertebrae. Some of the bones of the feet distal to the radius and tibia are with the skeleton, and the remainder probably are in the skin. The skin is fairly well made and in good condition, except for the left hind leg which was torn when the animal was captured. A well-developed scrotal pouch shows the specimen to have been a male.
Range.—Altitudinally around 300 feet in San Joaquin Valley to 2500 feet at Isabella; Upper Sonoran and Lower Sonoran life-zones of southern end of San Joaquin Valley and in mountains at southern end of Valley, California. See figures [29] and [30] on pages 221 and 314.
Characters for ready recognition.—Differs from M. f. nevadensis in presence of light facial markings, and from M. f. nevadensis and M. f. inyoensis in near (16 j) Buckthorn Brown to near (h) Yellow Ocher rather than near (14 n to l) Brussels Brown color of upper parts, and greater size with hind foot more than 40 in females and basilar length averaging more than 46.0 in males; from M. f. latirostra in having rostrum (orbitonasal length) longer than tympanic bulla and from M. f. latirostra and M. f. nigriauris by color of upper parts as stated above rather than near (l) Antique Brown, and by having inside of ears same color as back rather than much darker than back; from M. f. xanthogenys in hind foot of males more than 46 and broader skull which in males has breadth of rostrum more than 13.9 and mastoid breadth more than 26.0.
Description.—Size.—Male: The type specimen and five other adults yield average and extreme measurements as follows: Total length, 454 (428-477); length of tail, 178 (153-184); length of hind foot, 50 (47-55). Tail averages 65 per cent as long as head and body. Length of hind foot approximately equal to basal length. The type specimen measures, 460, 184, 49.
Female: Three subadult topotypes yield average and extreme measurements as follows: Total length, 399 (383-411); length of tail, 154 (140-161); length of hind foot, 42 (41-42). Tail averages 63 per cent as long as head and body. Length of hind foot less than basal length.
The average differences in external measurements of the two sexes are: Total length, 55; length of tail, 24; length of hind foot, 8.
Externals.—As described in Mustela frenata nigriauris.
Color.—Spot between eyes, band confluent with color of underparts, on each side of head extending anterodorsally anterior to each ear, posterior third of each upper lip, lower lips and chin white or more often darker than Ochraceous-Buff and therefore same color as belly; dark spot posterior to each angle of mouth present but small; tip of tail black; remainder of upper parts near (16 j) Buckthorn Brown to near (h) Yellow Ocher and from tone 2 to 4 of Brown Pink of Oberthür and Dauthenay, pl. 297, but with a trifle more reddish brown. Upper parts of uniform color except for occasional slight darkening of nose, forehead, and areas around eyes. Underparts darker (a) than Ochraceous-Buff. Color of underparts extends distally on posterior sides of forelegs over toes, onto antipalmar faces of feet and wrists, on medial sides of hind limbs over antiplantar faces of toes, tarsal region and sometimes in diluted fashion on proximal third of underside of tail. Least width of color of underparts averaging, in 6 male topotypes, 55 (43-81) per cent of greatest width of color of upper parts. Black tip of tail in same series of males averaging 58 (53-63) mm. long; thus averaging longer than hind foot and 33 per cent of length of tail-vertebrae.
Skull and teeth.—Male (based on 6 ads., type and 5 topotypes): See measurements and plates [22]-[24]. As described in M. f. nigriauris except that: Weight (6 ads.), 5.3 (4.5-6.1) grams; basilar length, 47.6 (46.0-48.6); (one skull, no. 335, with postorbital breadth more than distance between posterior borders of P4 and P2); interorbital breadth more or less than distance between foramen opticum and anterior margin of tympanic bulla; anterior margin of tympanic bulla as far posterior to foramen ovale as width of 2 to 3-1/2 (including I3) upper incisors; length of tympanic bulla more than length of lower molar and premolar tooth-row and shorter than rostrum.
Female: Adult skull of typical female not seen.
As compared with the skull of the type specimen of inyoensis, skulls of adult males of pulchra are larger throughout, relatively broader, especially in the preorbital part of the skull, have more inflated tympanic bullae, and are less convex in dorsal outline. Comparison of the skull with that of latirostra has been made in discussion of that subspecies. Comparison of skulls of adult males of nigriauris and pulchra shows that those of pulchra average larger in every measurement taken except those of m1, M1, P4, and depth of skull at posterior borders of upper molars. The basilar length is only slightly more and it follows that, relative to this length, other measurements of the skull are relatively, as well as actually, larger. In no one measurement is there an entire lack of overlap, but the skulls of adult males, and probably adult females, may be distinguished from those of nigriauris by the combination of the following mentioned, average differences: Tympanic bullae larger in each of three dimensions; preorbital and interorbital parts of skull broader and notably heavier; interorbital breadth greater; zygomatic arches more expanded laterally; mastoid processes more prominent. As compared with xanthogenys, differences of similar nature, but of greater degree, distinguish pulchra. As compared with those of nevadensis (represented by specimens from Mono Co., Calif.), skulls of adult males of pulchra average larger in every measurement taken and no overlap exists in basilar length, orbitonasal length, mastoid breadth, zygomatic breadth, length of tympanic bulla, or depth of skull at either the anterior margin of the basioccipital or at the posterior margins of the upper molars. Relatively, the preorbital portion is about the same size in the two forms.
Remarks.—The best material of this big weasel was obtained in 1910 and 1911 by John Wimmer and forwarded to the California Academy of Sciences through John R. Rowley, although in 1905, one specimen had been obtained by A. S. Bunnell for the collections of the United States Bureau of Biological Survey, another by J. Grinnell for the Museum of Vertebrate Zoölogy in 1912, and in 1933, another by L. M. Huey, for the San Diego Society of Natural History.
The males from the type locality are relatively uniform in size and shape of skull. The one exception is no. 137935, U. S. Nat. Mus., slightly younger than the others. Its skull is relatively more slender than any of the others and does not display several of the differential characters. The male, no. 127566, U. S. Nat. Mus., from Alila (= Earlimart) is intermediate in cranial features between pulchra and xanthogenys as known from specimens taken in the vicinity of Fresno. The skull of the female, no. 127565, from the same place, is too young to provide diagnostic characters. Since the skull of an adult female of topotypical pulchra is unknown, doubt attaches to the identification of the adult, female specimen, no. 115895, U. S. Nat. Mus., from Delano. It has a relatively broad skull in comparison with the adult female of xanthogenys from Los Banos. The adult female, no. 9998, San Diego Soc. Nat. Hist., from 2 mi. SW Simmler, shows approach to nigriauris in slightly reduced size. The skin alone from Coalinga, a male, taken on April 10, 1935, measures 462, 179, 47. The adult female, with crushed skull, from 4 miles east of Coalinga, measures 350, 129, 40. In size, these specimens agree better with pulchra than with xanthogenys. The skin alone from 3 miles south of Coalinga is unsexed and without external measurements. Skulls of adults from Coalinga are needed to permit of more positive identification of the subspecies found there. The female from 4 miles east of Coalinga, taken on February 21, 1936, is in process of molt on the underparts, and the longer hair which is near (20´) Naples Yellow contrasts strongly with the incoming shorter hair which is near (10 c) Salmon-Orange. The skin alone, no. 16270, Mus. Vert. Zoöl., from Isabella, was made up from a decayed animal and is of but little use. It is referred to pulchra purely because of geographic nearness of Isabella to the type locality of pulchra. The most that can be told from the specimen is that it is a relatively light-colored, bridled weasel. The fact that the color is slightly darker than in pulchra may or may not indicate intergradation with nevadensis. No. 54103/41042, U. S. Nat. Mus., consisting of crushed bits of skull and the skin of the head, is from Willow Spring, Kern County. This marginal locality is really in the Mojave Desert rather than in the San Joaquin Valley. The light color of the skin of the head suggests pulchra, but it is realized that a complete specimen might show the animal there to be unlike pulchra.
None of the skulls shows evidence of having had the frontal sinuses infested by parasites.
Specimens examined.—Total number, 18, listed by counties from north to south. Unless otherwise indicated, specimens are in the Museum of Vertebrate Zoölogy.
California. Fresno County: Coalinga, 1[23]; 4 mi. E Coalinga, 1; 3 mi. S Coalinga, 1[8]. Tulare County: Alila (= Earlimart), 2[91]. Kern County: Delano, 1[91]; Buttonwillow, 9 (6[8], 2[91]); Isabella, 1; Willow Spring, 1[91] San Luis Obispo County: 2 mi. SW Simmler, 1[87].