Specimens examined.—Total, 18 (all in Museum of Zoölogy, University of Michigan), distributed as follows:Daggett County: Sheep Creek, 4; 1 mi. W Summit Springs, 4; Beaver Creek, 22 mi. S Manila, 9; Granite Park, 24 mi. S Manila, 1.
Specimens examined.—Total, 18 (all in Museum of Zoölogy, University of Michigan), distributed as follows:Daggett County: Sheep Creek, 4; 1 mi. W Summit Springs, 4; Beaver Creek, 22 mi. S Manila, 9; Granite Park, 24 mi. S Manila, 1.
Type.—Male, adult, skin and skull, No. 13690, Carnegie Museum; Vernal-Manila Highway, 19 mi. N Vernal, 8,000 ft., Uintah County, Utah; August 22, 1937; collected by J. K. and M. T. Doutt; original number 4718.
Range.—Uinta Mountains in Daggett, northern Uintah and northern Summit counties.
Diagnosis.—Size large (see measurements); ears relatively narrow; hind foot relatively small. Color: Upper parts between Drab and Light Drab, darkest along middorsal line due to mixture of hairs tipped with light brown; sides and flanks Light Drab; entire underparts creamy white; front and hind feet, ventral surface of tail and end of tail white; proximal two-thirds of tail covered dorsally with light brown hairs; nose and cheeks dusky; postauricular patches black. Skull: Large, heavy and ridged; rostrum long and narrow; nasals long, moderately dilated distally and with a distal hump; posterior ends of nasals emarginate; parietal and lambdoidal crests well developed; zygomatic arches moderately heavy and widely spreading, widest posteriorly; zygomatic processes of maxillae moderately heavy and flaring abruptly from base of rostrum; marked middorsal depression in frontals present; interparietal pentagonal; extension of premaxillae posterior to nasals long; posterior tongues of premaxillae long, slender and rounded proximally; braincase high, vaulted and relatively narrow; tympanic bullae well inflated ventrally, and ridged in old animals; pterygoid hamulae long; interpterygoid space narrowly V-shaped; upper incisors long and narrow; molariform teeth medium.
Comparisons.—Compared with topotypes ofThomomys talpoides bridgeri,ravusdiffers as follows: Size larger; hind foot smaller; ears narrower. Color: Lighter throughout, grayish as opposed to brown. Skull: Smaller, narrower, less angular and less massive; nasals, rostrum, zygomatic processes of maxillae, ascending branches of premaxillae and posterior tongues of premaxillae all narrower; extension of premaxillae posterior to nasals longer; interparietal wider; braincase higher and narrower; tympanic bullae approximately the same size, but more inflated ventrally; interpterygoid space more narrowly V-shaped; upper incisors narrower; molariform teeth weaker.
Compared with topotypes and near topotypes ofThomomys talpoides uinta,ravusdiffers as follows: Size larger in every measurement taken. Color: Lighter throughout, being grayish as opposed to brown. Skull: Larger in every measurement taken; rostrum and nasals actually as well as relatively longer; extension of premaxillae posterior to nasals longer; upper incisors longer and wider; molariform teeth larger.
There is only one other gray subspecies ofThomomys talpoidesin Utah,Thomomys talpoides ocius. Topotypes ofravusdiffer from it as follows: Size markedly larger in every measurement taken. Color: Darker, more brown hairs. Skull: Larger in every measurement taken; premaxillae extended farther posteriorly to nasals; extension of supraoccipital posterior to lambdoidal suture markedly less; tympanic bullae actually as well as relatively smaller; upper incisors longer and more procumbent.
This new subspecies can be readily distinguished from all other subspecies ofThomomys talpoidesoccurring in Utah by markedly greater size and paler, more grayish color.
Remarks.—The range of this form appears to be limited to the north slopes of the Uinta Mountains, except in Daggett County where it occurs also on the south slopes. Intergradation in color and in cranial details withbridgeriis shown by animals from the East Fork of Blacks Fork, thirty-one miles SSW Fort Bridger, and by those from Henrys Fork, 8,300 ft., both in Summit County. Due to the grayish color and the narrower, weaker skull they are referred toravus. Intergradation withuintais shown by specimens from the type locality of the latter race. The type series ofuintaconsists of intergrades betweenravusand the animals to the west and south (see remarks underuinta).
It is doubtful whetherbridgerioccurs in Utah. Material from Rich County and extreme northern Cache County would settle the question. Perhapsbridgeriis restricted to the lower valleys in southwestern Wyoming. Two specimens from northern Cache County, from Logan Canyon, Beaver Basin, Utah-Idaho Line appear to be intergrades betweenbridgeriandwasatchensis, but are referable to the latter race.
Specimens examined.—Total, 38, distributed as follows:Summit County: Henrys Fork, 8,300 ft., 8; E Fork, Blacks Fork, 31 mi. SSW Fort Bridger, 4 (C. M.).Daggett County: Vernal-Manila Road, 4 mi. W Green's Lake, 7,500 ft., 6 (C. M.); Elk Park, Uinta Mountains, 5 (B. Y. U.).Uintah County: Trout Creek, SE Trout Peak, 22 mi. NW Vernal, 9,300 ft., 5 (C. M.); Vernal-Manila Highway, 19 mi. N Vernal, 8,000 ft., 6 (C. M.); Taylor Peak, 17 mi. N Vernal, 4 (C. M.).
Specimens examined.—Total, 38, distributed as follows:Summit County: Henrys Fork, 8,300 ft., 8; E Fork, Blacks Fork, 31 mi. SSW Fort Bridger, 4 (C. M.).Daggett County: Vernal-Manila Road, 4 mi. W Green's Lake, 7,500 ft., 6 (C. M.); Elk Park, Uinta Mountains, 5 (B. Y. U.).Uintah County: Trout Creek, SE Trout Peak, 22 mi. NW Vernal, 9,300 ft., 5 (C. M.); Vernal-Manila Highway, 19 mi. N Vernal, 8,000 ft., 6 (C. M.); Taylor Peak, 17 mi. N Vernal, 4 (C. M.).
Thomomys clusius ociusMerriam, Proc. Biol. Soc. Washington, 14:114, July 19, 1901.Thomomys clusiusAllen, Bull. Amer. Mus. Nat. Hist., 13:246, November 25, 1896.Thomomys ociusBailey, N. Amer. Fauna, 39:107, November 15, 1915; Barnes, Bull. Univ. Utah, 12 (No. 15):83, April, 1922; Bull. Univ. Utah, 17 (No. 12):102, June, 1927.
Thomomys clusius ociusMerriam, Proc. Biol. Soc. Washington, 14:114, July 19, 1901.
Thomomys clusiusAllen, Bull. Amer. Mus. Nat. Hist., 13:246, November 25, 1896.
Thomomys ociusBailey, N. Amer. Fauna, 39:107, November 15, 1915; Barnes, Bull. Univ. Utah, 12 (No. 15):83, April, 1922; Bull. Univ. Utah, 17 (No. 12):102, June, 1927.
Type.—Male, adult, skin and skull, No. 18852/25586, U. S. National Museum (Biological Surveys Collection); dry sagebrush mesas at Harveys Ranch, Smiths Fork, 6 mi. SW Fort Bridger, 6,657 ft., Uinta County, Wyoming; May 24, 1890; collected by Vernon Bailey; original number 1194 (after Bailey, type not seen).
Diagnosis.—Size small (see measurements). Color: Upper parts Tilleul Buff overlaid with Avellaneous, grading over sides and flanks to nearly white on underparts; underparts with faint wash of creamy white; postauricular patches small and dusky and completely circling the ear; nose and cheeks dusky; front feet, hind feet, throat, ventral surface of tail and distal half of tail white. Skull: Small, slender but compact; nasals rounded posteriorly; extension of premaxillae posterior to nasals very short; zygomatic arches robust, but not widely spreading, widest posteriorly; interparietal large and pentagonal in shape; extension of supraoccipital posterior to lambdoidal suture long; tympanic bullae actually as well as relatively large; basioccipital narrow; pterygoid hamulae long and ridged; upper incisors short and strongly recurved.
Comparisons.—Compared with one topotype and seven near topotypes ofThomomys talpoides pygmaeus,ociusdiffers as follows: Size larger in every measurement taken. Color: Lighter throughout, grayish as opposed to brown; distal half of tail white as opposed to only a few white hairs at tip of tail. Skull: Larger in every measurement taken; skull more compact; zygomatic archesheavier and more widely spreading posteriorly; tympanic bullae larger; upper incisors larger, but equally strongly recurved; molariform teeth larger.
Topotypes of ocius can be distinguished from those ofThomomys talpoides uintaas follows: Color: Lighter throughout, grayish as opposed to brown. Skull: Nasals rounded posteriorly as opposed to emarginate; zygomatic arches more robust; interparietal pentagonal as opposed to subquadrangular; extension of supraoccipital posterior to lambdoidal suture markedly greater; tympanic bullae actually as well as relatively much larger; upper incisors short and strongly recurved as opposed to long and procumbent.
Specimens of this subspecies can be distinguished from all other members of the speciesThomomys talpoidesoccurring in Utah by their grayish color, and by small, compact skulls with very large tympanic bullae and short strongly recurved upper incisors.
Remarks.—Two specimens from Vernal, Uintah County, are intergrades betweenociusanduinta. They resembleuintain size and dorsal color, but are slightly lighter tending toward the color ofocius. Ventrally they are intermediate in color but more likeocius. The skulls are more like those ofociusin general appearance, extension of supraoccipital posterior to the lambdoidal suture, shape and thickness of the zygomatic arches, posterior tongues of premaxillae, size of tympanic bullae and recurved upper incisors. They more closely resembleuintain shape of posterior ends of nasals, basioccipital and shape of the zygomatic processes of the squamosals. In all of the above mentioned characters, they are intermediate between the two named forms, but tend towards one or the other as listed. The majority of characters are more as inociusto which they are here referred.
When Goldman (1939:233, 234) listed the named subspecies ofThomomys talpoides, he hesitated to includeociusand merely mentioned thatocius,pygmaeusandidahoensismight also belong totalpoides. Davis (1939:240, 241) found intergradation betweenidahoensisandfuscusand also betweenidahoensisandpygmaeus, and, therefore, arranged the last two mentioned forms as subspecies oftalpoides. This present study reveals intergradation betweenociusanduinta, and also betweenociusandfossor(see account offossor). Therefore,ociusis properly to be treated as a subspecies of the series of intergrading forms of whichtalpoidesis the earliest named.
All specimens ofociusknown from Utah are from the extremeeastern part of the northeastern corner of the state. The type locality ofociusis near Fort Bridger, Wyoming, which is north of Utah. I have seen one specimen from 12 miles west of Linwood, Daggett County, Utah, on Henrys Fork in Wyoming. Additional collecting in northern Utah probably will revealociusto inhabit also parts of northern Utah.
Specimens examined.—Total, 4, distributed as follows:Uintah County: Vernal, 2 (C. M.); Uncompahgre Indian Reservation, 2 (A. M. N. H.).
Specimens examined.—Total, 4, distributed as follows:Uintah County: Vernal, 2 (C. M.); Uncompahgre Indian Reservation, 2 (A. M. N. H.).
Thomomys fossor mooreiGoldman, Journ. Washington Acad. Sci., 28:335, July 15, 1938.Thomomys talpoides mooreiGoldman, Journ. Mamm., 20:234, May 14, 1939.
Thomomys fossor mooreiGoldman, Journ. Washington Acad. Sci., 28:335, July 15, 1938.
Thomomys talpoides mooreiGoldman, Journ. Mamm., 20:234, May 14, 1939.
Type.—Male, adult, skin and skull, No. 248222, U. S. National Museum (Biological Surveys Collection); 1 mi. S Fairview, 6,000 ft., Sanpete County, Utah; February 19, 1928; collected by A. W. Moore; X-catalogue number 24799 (after Goldman, type not seen).
Range.—Wasatch Plateau in Sanpete, Utah, Carbon and Emery counties, and in Wasatch Mountains south of Spanish Fork Canyon.
Diagnosis.—Size medium (see measurements). Color: Upper parts between Cinnamon and Sayal Brown, with mixture of black hairs, grading through Cinnamon on sides and flanks to Pale Pinkish Buff on underparts, clearest on inguinal and pectoral regions; nose and cheeks dusky; postauricular patches medium in size and black; ears black; chin buffy white; front and hind feet white; tail mostly white with brownish hairs on dorsal surface. Skull: Large, robust; nasals long and deeply emarginate on posterior ends, and dilated distally; zygomatic arches robust and widely spreading; zygomatic processes of maxillae heavy; interparietal comparatively small, but always wider than long; extension of premaxillae posterior to nasals short; tympanic bullae moderate in size, but markedly inflated ventrally; pterygoid hamulae long; interpterygoid space narrowly V-shaped; upper incisors long and moderately recurved; molariform teeth light.
Comparisons.—Topotypes ofmooreidiffer from topotypes and near topotypes ofThomomys talpoides uintaas follows: Size slightly larger. Color: Upper parts and sides lighter; tail lighter; postauricular patches larger and darker; ears more pointed, smaller and darker. Skull: Larger, heavier and more massive; nasals longer, but deeply emarginate posteriorly as inuinta; rostrum wider and longer; zygomatic arches heavier and more angular; zygomatic processes of maxillae heavier; interparietal generally smaller and shorter; braincase wider; tympanic bullae more inflated ventrally; interpterygoid space more narrowly V-shaped; upper incisors longer, but not as procumbent; molariform teeth smaller.
Topotypes ofmooreican be distinguished from those ofThomomystalpoides oquirrhensisas follows: Size slightly larger; tail longer; ears larger, less pointed. Color: Lighter throughout; postauricular patches larger. Skull: More ridged and angular; nasals narrower posteriorly, but more dilated distally; posterior ends of nasals more deeply emarginate (while shallowly emarginate inoquirrhensis, they tend to be somewhat rounded); rostrum narrower; extension of premaxillae posterior to nasals greater; least interorbital breadth less; zygomatic arches more angular and widely spreading; zygomatic processes of maxillae heavier; interparietal smaller; tympanic bullae larger and more inflated ventrally; upper incisors generally longer.
The characters that distinguishmooreifromThomomys talpoides parowanensisare: Color: Lighter throughout. Skull: Broader, more angular and more nearly flat; zygomatic arches more widely spreading; zygomatic processes of maxillae heavier; posterior ends of nasals emarginate rather than rounded; upper incisors longer.
For comparisons ofmooreiwithThomomys talpoides levisandwasatchensissee accounts of these forms.
Remarks.—Specimens from Colton, show intergradation betweenmoorei,uintaandwasatchensis, but are referable tomooreiin the majority of characters. Specimens from Mount Nebo, and the mouth of Reddicks Canyon, in the Wasatch and San Pitch mountains, respectively, are intergrades betweenmooreiandwasatchensis, but are referable tomoorei.
That part of the Wasatch Mountains south of Spanish Fork Canyon is inhabited by pocket gophers that are intergrades betweenmooreiandwasatchensis, but the cranial details show them to be referable tomoorei. The range here ascribed tomooreiconsists of the Wasatch Plateau to the east of Sanpete Valley, the San Pitch Mountains and the southern part of the Wasatch Mountains. The type locality ofmooreiis situated in the southern end of a high valley that separates the Wasatch Plateau from the San Pitch and Wasatch mountains. Topotypical animals are larger and have more ridged, angular skulls than those from the mountains.
Specimens examined.—Total, 48, distributed as follows:Utah County: Near Payson Lake, 1 (R. H.); Mt. Nebo, 25 mi. SE Payson, 10,000 ft., 20; Colton, 8 (B. Y. U.).Sanpete County: 1 mi. S Fairview, 6,000 ft., 12 (U. S. N. M.).Juab County: Mouth of Reddicks Canyon, Wales Mountain (= San Pitch Mountains), 7,500 ft., 5.Emery County: Lake Creek, 11 mi. E Mt. Pleasant, 2 (C. M.).Additional records.—Sanpete County: Ephraim, 5 (see Goldman, 1938:336).
Specimens examined.—Total, 48, distributed as follows:Utah County: Near Payson Lake, 1 (R. H.); Mt. Nebo, 25 mi. SE Payson, 10,000 ft., 20; Colton, 8 (B. Y. U.).Sanpete County: 1 mi. S Fairview, 6,000 ft., 12 (U. S. N. M.).Juab County: Mouth of Reddicks Canyon, Wales Mountain (= San Pitch Mountains), 7,500 ft., 5.Emery County: Lake Creek, 11 mi. E Mt. Pleasant, 2 (C. M.).
Additional records.—Sanpete County: Ephraim, 5 (see Goldman, 1938:336).
Thomomys fossorAllen, Bull. Amer. Mus. Nat. Hist., 5:51, April 28, 1893; Bailey, N. Amer. Fauna, 39:111, November 15, 1915; Barnes, Bull. Univ. Utah, 12 (No. 15):85, April, 1922; Bull. Univ. Utah, 17 (No. 12):102, June, 1927; Hall, Univ. California Publ. Zoöl., 37:4, April 10, 1931.Thomomys talpoides fossorGoldman, Journ. Mamm., 20:234, May 14, 1939.
Thomomys fossorAllen, Bull. Amer. Mus. Nat. Hist., 5:51, April 28, 1893; Bailey, N. Amer. Fauna, 39:111, November 15, 1915; Barnes, Bull. Univ. Utah, 12 (No. 15):85, April, 1922; Bull. Univ. Utah, 17 (No. 12):102, June, 1927; Hall, Univ. California Publ. Zoöl., 37:4, April 10, 1931.
Thomomys talpoides fossorGoldman, Journ. Mamm., 20:234, May 14, 1939.
Type.—Male, adult, skin and skull, No. 5240/4120, American Museum of Natural History; Florida, 7,200 ft., La Plata County, Colorado; June 25, 1892; collected by Charles P. Rowley (after Allen, type not seen).
Range.—In the mountains of San Juan and Grand counties, east of the Colorado and Green rivers.
Diagnosis.—Size medium (see measurements). Color: Upper parts Dresden Brown, grading over sides to Pale Buff on underparts; chin white; ears small, pointed, with deeply pigmented pinnae; postauricular patches grayish black; nose dusky. Skull: Long and narrow; nasals long, rounded proximally and usually simple distally; rostrum long; interparietal triangular; tympanic bullae large, and well inflated ventrally; basioccipital narrow; palate narrow; palatal pits shallow; dentition light.
Comparisons.—Near topotypes offossorcan be distinguished from topotypes ofThomomys talpoides ociusas follows: Size larger throughout. Color: Darker throughout, being dark brown as opposed to grayish. Skull: Longer and narrower; nasals and rostrum longer; extension of supraoccipital posterior to lambdoidal suture markedly less; tympanic bullae markedly smaller; upper incisors longer and not as strongly recurved.
Among the races ofThomomys talpoidesoccurring in Utah,fossormost closely resemblesThomomys talpoides uintain color and size, but differs from it as follows: Ears smaller, more pointed and with more darkly pigmented pinnae. Skull: Longer, narrower and weaker; rostrum longer; nasals longer, and rounded proximally as opposed to markedly emarginate; interparietal triangular instead of roughly pentagonal; tympanic bullae larger and more inflated ventrally; basioccipital narrower; palate narrower, palatal pits shallower; dentition lighter.
Remarks.—Bailey (1915:111) remarked thatfossorwas one form that held its distinctive characters over a wide range. At that time, its range was understood to include practically all of the mountainous parts of Colorado, Utah as far west as the central part of the state, and parts of New Mexico, Arizona and Wyoming. Subsequently three new forms have been named from central Utah, (Goldman 1938:334-337) thereby showing variation to be muchmore prevalent than formerly supposed. The range offossorin Utah, as now understood, is limited to the mountainous parts of the state south and east of the Colorado and Green rivers in Grand and San Juan counties.
The Utah specimens are not typical. At first glance some differences are noted in the premaxillae and nasals. Four specimens in the collections of the Museum of Natural History, University of Kansas, three from 3 miles east of Creede, Mineral County, and one from 10 miles east of Lake City, Hinsdale County, Colorado, both of which lie north and east of the type locality offossorshow the same characters as the Utah specimens.
Eight specimens from Oak Spring are intergrades betweenfossorandocius. In size and color they are likefossor, but the skulls are intermediate. Because the animals are more likefossorin the majority of characters, they are here referred to that race.
As a result of these studies and due to the paucity of specimens from Utah, it is advisable, for the present, to refer all these Utah animals tofossor. Additional specimens may reveal characters that will merit the separation of the Utah animals from typicalfossor; a desertlike area unfavorable toThomomysexists between the type locality and eastern Utah.
Specimens examined.—Total, 21, distributed as follows:Grand County: Oak Spring, Middle Fork Willow Creek, 15 mi. N Thompson, 8 (C. M.); La Sal Mountains, 1 (U. S. N. M.); Warner Ranger Station, La Sal Mountains, 3 (B. Y. U.).San Juan County: Geyser Pass, 18 mi. SE Moab, La Sal Mountains, 3 (1, B. Y. U.; 2, C. M.); 5 mi. W Monticello, 1 (C. M.); Cooley Pass, 8 mi. W Monticello, 2 (C. M.); Joshua Flat, Elk Ridge, 8,300 ft., 3 (M. V. Z.).
Specimens examined.—Total, 21, distributed as follows:Grand County: Oak Spring, Middle Fork Willow Creek, 15 mi. N Thompson, 8 (C. M.); La Sal Mountains, 1 (U. S. N. M.); Warner Ranger Station, La Sal Mountains, 3 (B. Y. U.).San Juan County: Geyser Pass, 18 mi. SE Moab, La Sal Mountains, 3 (1, B. Y. U.; 2, C. M.); 5 mi. W Monticello, 1 (C. M.); Cooley Pass, 8 mi. W Monticello, 2 (C. M.); Joshua Flat, Elk Ridge, 8,300 ft., 3 (M. V. Z.).
Thomomys fossor parowanensisGoldman, Journ. Washington Acad. Sci., 28:334, July 15, 1938.Thomomys talpoides parowanensisGoldman, Journ. Mamm., 20:234, May 14, 1939; Long, Journ. Mamm., 21:176, May 14, 1940.Thomomys fossorBailey, N. Amer. Fauna, 39:112, November 15, 1915; Barnes, Bull. Univ. Utah, 12 (No. 15):85, April, 1922; Bull. Univ. Utah, 17 (No. 12):102, June, 1927; Hall, Univ. California Publ. Zoöl., 37:4, April 10, 1931; Presnall, Zion-Bryce Mus. Bull., 2:14, January, 1938; Tanner, Great Basin Nat., 1:111, 1940.
Thomomys fossor parowanensisGoldman, Journ. Washington Acad. Sci., 28:334, July 15, 1938.
Thomomys talpoides parowanensisGoldman, Journ. Mamm., 20:234, May 14, 1939; Long, Journ. Mamm., 21:176, May 14, 1940.
Thomomys fossorBailey, N. Amer. Fauna, 39:112, November 15, 1915; Barnes, Bull. Univ. Utah, 12 (No. 15):85, April, 1922; Bull. Univ. Utah, 17 (No. 12):102, June, 1927; Hall, Univ. California Publ. Zoöl., 37:4, April 10, 1931; Presnall, Zion-Bryce Mus. Bull., 2:14, January, 1938; Tanner, Great Basin Nat., 1:111, 1940.
Type.—Male, adult, skin and skull, No. 158072, U. S. National Museum (Biological Surveys Collection); Brian Head, Parowan Mountains, 11,000 ft., Iron County, Utah; September 8, 1908; collected by W. H. Osgood; original number 3483 (after Goldman, type not seen).
Range.—High mountains of eastern Iron and Beaver counties, and western Kane and Garfield counties.
Diagnosis.—Size medium (see measurements). Color: Upper parts Sayal Brown moderately mixed with black, lightest on head; sides lightly washedwith Buff; underparts Pinkish Buff, clearest on inguinal and pectoral regions; nose and cheeks dusky; postauricular patches large and black; front feet, hind feet and distal half of tail white. Skull: Long and fairly slender; zygomatic arches not widely spreading; nasals long; rostrum long and slender; posterior ends of nasals truncate or moderately emarginate; extension of premaxillae posterior to nasals usually short; tympanic bullae relatively small; upper incisors long and narrow; molariform teeth large.
Comparisons.—Compared withThomomys talpoides kaibabensis,parowanensisdiffers as follows: Size smaller. Skull: Shorter; nasals shorter; zygomatic breadth less; nasals truncate or shallowly emarginate posteriorly as opposed to rounded; upper incisors narrower.
Topotypes ofparowanensisdiffer from topotypes and near topotypes ofThomomys talpoides uintaas follows: Size larger. Color: Usually lighter; postauricular patches larger and darker; ears small with pinnae deeply pigmented as opposed to large and lightly pigmented. Skull: Larger; zygomatic arches more widely spreading; nasals longer; rostrum longer; posterior ends of nasals truncate or shallowly emarginate as opposed to deeply emarginate; sides of zygomatic arches nearly parallel and not so divergent posteriorly; interparietal larger and less quadrangular; extension of premaxillae posterior to nasals less; upper incisors less procumbent; molariform teeth larger.
Among named races ofThomomys talpoides,parowanensismost closely resembleslevis, the race nearest geographically to the east, but differs fromlevisas follows: Size larger. Skull: Longer and wider; rostrum and nasals longer; interparietal quadrangular as opposed to roughly elliptical; upper incisors longer.
For comparisons withThomomys talpoides mooreiandwasatchensissee accounts of those forms.
Remarks.—The mountains of south central Utah are inhabited by pocket gophers that have been designated asThomomys talpoides parowanensisandT. t. levisby Goldman (1938:334, 336). They are nearly indistinguishable in color and each is variable in cranial details. The diagnostic characters of each form occasionally appear, in varying degrees, throughout the range of the other. The Sevier River Valley separates the ranges ascribed to these two forms. This valley is inhabited by pocket gophers that belong to a different species,Thomomys bottae. The ranges of these two races oftalpoidesconverge southward at the headwaters of the Sevier River. Specimens ofparowanensisfrom the northern limits of its range from the Beaver Mountains in eastern Beaver Countyand those oflevisfrom the northern limits of its range in the Fish Lake Mountains are readily distinguishable from each other. As the ranges converge to the southward, there is progressively more intergradation. The type locality ofparowanensisis located in the southern part of its range, while that oflevisis in the extreme northern part of its range. Therefore, due to the convergence of the two ranges at the south, the specimens from localities near the type locality ofparowanensisshow the greatest amount of intergradation, if we regard specimens ofparowanensisfrom the type locality as typical of the race. Four specimens from Webster Flat, sixteen miles east of Cedar City, Iron County, and three from Duck Creek, Cedar Mountains, Kane County could equally well be assigned to eitherlevisorparowanensis.
Specimens examined.—Total, 24, distributed as follows:Beaver County: Britts Meadows, Beaver Mountains, 8,500 ft., 7 (3, M. V. Z.; 2, U. S. N. M.; 2, C. M.); Puffer Lake, Beaver Mountains, 1 (U. S. N. M.); Kents Lake, Beaver Mountains, 1 (R. H.).Iron County: Lava Beds, 3-1/2 mi. SW Panquitch Lake, 1 (C. M.); Brian Head, Parowan Mountains, 2 (1, U. S. N. M.; 1, C. M.); Webster Flat, 16 mi. E Cedar City, 4; Bear Valley, 2 mi. E B. V. Ranger Station, 1 (R. H.).Garfield County: 1/4 mi. W Sunset Point, Bryce National Park, 8,000 ft., 1 (M. V. Z.).Kane County: Navajo Lake, 3 (R. H.); Duck Creek, Cedar Mountains, 9,000 ft., 3 (1, R. H.).Additional records.—Garfield County: Panquitch Lake, 1 (see Goldman 1938:335).Iron County: Beaver Mountains, 9 (see Bailey, 1915:112); Buckskin Valley, 1 (see Goldman, 1938:335).
Specimens examined.—Total, 24, distributed as follows:Beaver County: Britts Meadows, Beaver Mountains, 8,500 ft., 7 (3, M. V. Z.; 2, U. S. N. M.; 2, C. M.); Puffer Lake, Beaver Mountains, 1 (U. S. N. M.); Kents Lake, Beaver Mountains, 1 (R. H.).Iron County: Lava Beds, 3-1/2 mi. SW Panquitch Lake, 1 (C. M.); Brian Head, Parowan Mountains, 2 (1, U. S. N. M.; 1, C. M.); Webster Flat, 16 mi. E Cedar City, 4; Bear Valley, 2 mi. E B. V. Ranger Station, 1 (R. H.).Garfield County: 1/4 mi. W Sunset Point, Bryce National Park, 8,000 ft., 1 (M. V. Z.).Kane County: Navajo Lake, 3 (R. H.); Duck Creek, Cedar Mountains, 9,000 ft., 3 (1, R. H.).
Additional records.—Garfield County: Panquitch Lake, 1 (see Goldman 1938:335).Iron County: Beaver Mountains, 9 (see Bailey, 1915:112); Buckskin Valley, 1 (see Goldman, 1938:335).
Thomomys fossor levisGoldman, Journ. Washington Acad. Sci., 28:336, July 15, 1938.Thomomys talpoides levisGoldman, Journ. Mamm., 20:234, May 14, 1939.Thomomys fossorBailey, N. Amer. Fauna, 39:112, November 15, 1915; Barnes, Bull. Univ. Utah, 12 (No. 15):85, April, 1922; Bull. Univ. Utah, 17 (No. 12):102, June, 1927.
Thomomys fossor levisGoldman, Journ. Washington Acad. Sci., 28:336, July 15, 1938.
Thomomys talpoides levisGoldman, Journ. Mamm., 20:234, May 14, 1939.
Thomomys fossorBailey, N. Amer. Fauna, 39:112, November 15, 1915; Barnes, Bull. Univ. Utah, 12 (No. 15):85, April, 1922; Bull. Univ. Utah, 17 (No. 12):102, June, 1927.
Type.—Female, adult, skin and skull, No. 158079, U. S. National Museum (Biological Surveys Collection); Seven Mile Flat, 5 mi. N Fish Lake, Fish Lake Plateau, 10,000 ft., Sevier County, Utah; October 1, 1908; collected by W. H. Osgood; original number 3616 (after Goldman, type not seen).
Range.—Fish Lake Mountains in Sevier County south into Garfield County, Utah.
Diagnosis.—Size medium (see measurements). Color: Upper parts near Sayal Brown, moderately mixed with black, darkest on head and middorsal region, grading to Cinnamon Buff on sides and flanks; underparts Pinkish Buff, clearest on inguinal and pectoral regions; chin, cheeks and nose dusky; postauricular patches large and black; front feet, hind feet and distal half of tail white; ears small and deeply pigmented. Skull: Slender and weak; zygomatic arches not widely spreading; posterior ends of nasals rounded; nasals moderately long and narrow; rostrum long and narrow; extension of premaxillae posterior to nasals short; interparietal usually much wider thanlong; pterygoid hamulae ridged; interpterygoid space usually narrowly V-shaped; upper incisors short.
Comparisons.—Compared with topotypes ofThomomys talpoides moorei,levisdiffers as follows: Size smaller; tail shorter. Color: Darker throughout, especially on dorsal surface due to more black of the underfur; underparts deeper buff. Skull: Narrower, less massive; zygomatic processes of maxillae weaker and not as widely spreading; interparietal generally wider; extension of premaxillae posterior to nasals less; posterior ends of nasals rounded rather than emarginate; upper incisors shorter, less procumbent.
Topotypes oflevisdiffer from near topotypes ofThomomys talpoides uintaas follows: Size larger. Color: Upper parts slightly darker; postauricular patches much darker and larger; ears small and deeply pigmented as opposed to large and lightly pigmented; tail darker all around at base, with white part more extensive and with fewer buff-colored hairs. Skull: More convex dorsally; zygomatic arches more widely spreading and angular; nasals longer; rostrum longer; interparietal wider and more elliptical; posterior ends of nasals rounded as opposed to emarginate; extension of premaxillae posterior to nasals less; pterygoid hamulae more ridged; interpterygoid space more narrowly V-shaped; upper incisors shorter and less procumbent.
Topotypes ofleviscan be distinguished from those ofThomomys talpoides kaibabensisby markedly smaller measurements.
For comparisons withThomomys talpoides parowanensisandwasatchensissee accounts of those forms.
Remarks.—Specimens from the Escalante Mountains and the Aquarius Plateau are not typical. They are of approximately the same color aslevis, but are larger thanlevisand have cranial details that indicate intergradation withkaibabensisto the south. They resemblekaibabensisin large size, long nasals and widely spreading zygomatic arches, but are likelevisin shape of the interparietal, extension of premaxillae posterior to the nasals, rounded posterior ends of nasals, ridged pterygoid hamulae and relatively short upper incisors. Additional material from these regions may prove these animals to merit separation and naming.
Specimens examined.—Total, 15, distributed as follows:Sevier County: Seven Mile Flat, 5 mi. N Fish Lake, Fish Lake Plateau, 10,000 ft., 2 (U. S. N. M.); Fish Lake Experiment Station, 2 (U. S. A. C).Garfield County: Posy Lake, Aquarius Plateau, 2 (B. Y. U.); 18 mi. N Escalante, 9,500 ft., 3; Steep Creek, Boulder-Teasdale Road, Boulder Mountain, 4 (B. Y. U.); Summit Birch Creek, Escalante Mountains, 2 (B. Y. U.).
Specimens examined.—Total, 15, distributed as follows:Sevier County: Seven Mile Flat, 5 mi. N Fish Lake, Fish Lake Plateau, 10,000 ft., 2 (U. S. N. M.); Fish Lake Experiment Station, 2 (U. S. A. C).Garfield County: Posy Lake, Aquarius Plateau, 2 (B. Y. U.); 18 mi. N Escalante, 9,500 ft., 3; Steep Creek, Boulder-Teasdale Road, Boulder Mountain, 4 (B. Y. U.); Summit Birch Creek, Escalante Mountains, 2 (B. Y. U.).
Measurements of Adult Males of Thomomys
(In millimeters)
TotallengthLengthof tailLengthofhindfootBasilarlengthLengthofnasalsZygomaticbreadthMastoidbreadthInterorbitalbreadthAlveolarlengthofuppermolarseriesExtensionofpremaxpost. tonasalsLengthofrostrumBreadthofrostrumT. t. gracilis, 4; topotypesAv.204532831.513.421.718.36.47.61.315.47.2Min.194472730.312.921.117.86.37.31.014.76.7Max.210632833.514.222.019.06.57.91.716.47.5T. t. oquirrhensis, 4; topotypesAv.209582832.213.921.919.06.97.60.915.87.7Min.197552831.913.721.418.56.77.20.615.57.5Max.216602932.814.322.819.57.17.91.016.27.9T. t. wasatchensis, 10; topotypesAv.221672831.313.421.518.96.57.41.115.17.4Min.204602627.411.619.117.26.06.60.914.06.7Max.237753134.515.223.720.47.38.02.016.58.2T. t. uinta, 5; SW slope Bald Peak, Uinta Mts.Av.199512731.513.121.719.46.37.61.115.27.4Min.185472629.612.120.319.05.77.30.713.57.2Max.208542832.813.822.220.06.57.81.415.67.6T. t. moorei, 7; topotypesAv.216652932.413.922.919.26.57.71.515.97.3Min.203522731.313.021.518.46.07.30.914.86.7Max.236723134.714.523.720.07.08.22.016.37.7T. t. fossor, 8; Cascade Creek, La Plata Co., Colo.Av.215612931.713.221.218.75.97.50.615.57.1Min.202542730.512.020.518.25.57.00.014.56.9Max.228703033.014.423.519.96.37.91.116.97.4T. t. ravus, 3; topotypesAv.248733035.214.624.821.46.38.32.417.18.2Min.244702934.514.323.620.56.08.22.216.78.1Max.253743035.915.125.722.56.78.42.717.58.5No. 55270 (U. S. N. M.)T. t. pygmaeus, 1; topotype165402024.610.216.315.15.45.90.712.05.7No. 177506 (U. S. N. M.)T. t. ocius, 1; 12 mi. W Linwood, Henrys Fork, Wyo.200622627.511.519.917.86.26.81.013.57.0T. t. parowanensis, 2; Britts Meadow, Beaver MountainsAv.215592834.314.522.418.66.08.11.417.37.9Min.202482734.114.122.018.45.88.01.017.27.6Max.228692934.614.822.718.96.28.21.717.38.2
Measurements of Adult Females of Thomomys(In millimeters)
TotallengthLengthof tailLengthofhindfootBasilarlengthLengthofnasalsZygomaticbreadthMastoidbreadthInterorbitalbreadthAlveolarlengthofuppermolarseriesExtensionofpremaxpost. tonasalsLengthofrostrumBreadthofrostrumT. t. gracilis, 2; topotypesAv.190582729.712.019.717.36.47.31.214.06.5Min.185542729.511.919.716.96.37.21.114.06.4Max.194612729.912.019.717.66.57.41.414.06.6T. t. oquirrhensis, 7; topotypesAv.203562730.212.920.418.26.87.50.814.87.2Min.193522528.512.219.517.56.66.70.514.26.9Max.215592831.513.321.019.17.28.01.015.57.5T. t. wasatchensis, 19; topotypesAv.205622731.512.720.518.06.57.40.914.67.2Min.180522328.111.219.317.26.26.00.613.06.8Max.222703032.514.522.019.96.78.11.216.27.5T. t. uinta, 2; SW slope Bald Peak, Uinta Mts.Av.181492528.411.619.817.36.67.21.313.56.8Min.177472528.311.619.817.26.47.01.113.36.8Max.185502528.411.619.817.46.77.31.513.66.8T. t. moorei, 5; topotypesAv.206622629.912.821.518.46.67.31.314.66.8Min.198552429.012.321.018.06.47.01.014.06.4Max.213692831.214.122.519.16.87.51.615.67.0T. t. fossor, 4; Cascade Creek, La Plata Co., Colo.Av.215572932.614.222.019.06.07.50.716.27.3Min.204512831.313.621.518.05.77.10.515.97.0Max.223633034.014.822.919.66.37.81.016.37.5No. 13684 (C. M.)T. t. ravus, 1; topotype241712835.714.524.421.56.27.82.717.18.1No. 178868 (U. S. N. M.)T. t. pygmaeus, 1; Fossil, Wyo.167522024.010.216.514.85.25.60.711.15.8T. t. ocius, 3; topotypesAv.201602530.013.520.517.96.27.20.815.07.4Min196572529.913.019.917.56.17.10.514.77.3Max.205642530.114.021.518.66.37.31.015.37.5T. t. parowanensis, 4; Britts Meadow, Beaver MountainsAv.221582933.214.522.819.06.07.80.915.47.3Min.207502830.512.822.718.65.87.40.514.77.0Max.240663034.815.523.019.66.28.11.517.87.7T. t. levis, 2; topotypesAv.203652728.111.119.217.76.16.90.813.06.8Min.199612628.010.618.917.55.86.60.612.86.6Max.206702728.211.619.517.96.47.21.013.27.0
Thomomys bottaeis a southern species that, within the Great Basin, reaches the most northern limits of its distribution in Utah. The animals of this species inhabit the lower valleys, and with the exception of the Oquirrh Mountains, inhabit also the mountains in that part of the state west of the central mountain ranges. The specific characters are: Sphenorbital fissure present; incisive foramina posterior to infraorbital canal; anterior prism of P4 rounded; interparietal relatively small; lambdoidal suture straight in region of interparietal, in Utah specimens.