Geographic Range of the Hooded Skunk, Mephitis macroura, with Description of a New Subspecies from Mexico BY E. RAYMOND HALL and WALTER W. DALQUEST University of Kansas Publications Museum of Natural History Volume 1, No. 24, pp. 575-580, 1 figure in text January 20, 1950 University of Kansas LAWRENCE 1950 UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY Editors: E. Raymond Hall, Chairman, Edward H. Taylor, A. Byron Leonard, Robert W. Wilson Volume 1, No. 24, pp. 575-580, 1 figure in text January 20, 1950 UNIVERSITY OF KANSAS Lawrence, Kansas PRINTED BY FERD VOILAND, JR., STATE PRINTER TOPEKA, KANSAS 1950 23-1544 Geographic Range of the Hooded Skunk, Mephitis macroura, with Description of a New Subspecies from Mexico By E. RAYMOND HALL AND WALTER W. DALQUEST The hooded skunk, _Mephitis macroura_ Lichtenstein, can be distinguished from the only other species in the genus, _Mephitis mephitis_ Schreber, by the larger tympanic bullae, in the white-backed color phase by having some black hairs mixed with the white hairs of the back, and in the black-backed phase by having the two white stripes widely separated and on the sides of the animal instead of narrowly separated and on the back of the animal. The starting point for taxonomic work with _Mephitis_ is A. H. Howell's "Revision of the skunks of the genus Chincha (N. Amer. Fauna, 20, 1901)." Of the species _Mephitis macroura_, Howell (_op. cit._) recognized three subspecies: _M. m. macroura_, _M. m. milleri_, and _M. m. vittata_. The species _M. macroura_ is restricted to the arid region made up mostly of the Mexican Plateau. Also, wherever the species occurs beyond this Plateau, as for example in Guatemala, at San Mateo del Mar in Oaxaca, in the vicinity of Piedras Negras in Veracruz, and in southern Arizona, aridity is marked. Whether the species has a continuous distribution from the southern end of the Mexican tableland southward to Dueñas in Guatemala is not known but it is unlikely that the lowland population at San Mateo del Mar on the Pacific slope of Oaxaca has contact with _M. m. macroura_ of the Mexican Plateau and it is almost certain that the population, which is here named _M. m. eximius_, from the arid coastal plain of eastern Mexico in Veracruz, has no connection with the upland population, _M. m. macroura_. The lowest elevation on the eastern slope of the Plateau from which we have record of the occurrence of this species is 4,500 feet at Jico. All along the eastern slope of the Plateau, between the elevations of approximately 2,000 and 4,500 feet, the belt of lush, dense vegetation of the upper humid division of the Tropical Life-zone constitutes a barrier to _Mephitis_ and tends to exclude the hooded skunk from the arid territory below the humid belt. Another kind of skunk, _Conepatus tropicalis_, lives in the humid belt, at least on the eastern side of the Mexican tableland. How the population of _Mephitis_, which was sampled by us from west and west-northwest of Piedras Negras, arrived there is unknown but we think that its geographic range is not now connected with that of the population on the Plateau. The same can be said of the lowland population at San Mateo del Mar in Oaxaca. There, on the Pacific slope of the Mexican tableland, the lower humid division of the Tropical Life-zone probably has tended to restrict the spread southward and westward of _Mephitis_; however, on this Pacific slope the humid belt is less humid and it is less continuous, we think, than on the Atlantic slope. Four subspecies of _Mephitis macroura_ may be recognized. They are as follows: #Mephitis macroura milleri# Mearns 1897. _Mephitis milleri_ Mearns, Proc. U. S. Nat. Mus., 20:467, 1897. 1901. _Mephitis macroura milleri_, Bull. Amer. Mus. Nat. Hist., 14:334, November 12, 1901. _Type locality._--Fort Lowell, Pima County, Arizona. _Range._--Northwestern Mexico and southeastern Arizona. See figure 1. Marginal occurrences (unless otherwise indicated, after Howell, N. Amer. Fauna, 20:42, 43, 1901) are: _Arizona_: Santa Catalina Mountains; Tucson; Fort Lowell. _Chihuahua_: Casas Grandes; Chihuahua (City). _Coahuila_: La Ventura. _Chihuahua_: Guadalupe y Calvo (mountains near). _Sonora_: Camoa; Hermosillo; Sierra Cubabi (Burt, Miscl. Publ., Mus. Zool., Univ. Michigan, 39:30, 1938). _Characters._--Long skull ([Male] 60 mm, [Female] 56 mm) and large m1. #Mephitis macroura macroura# Lichtenstein 1832. _Mephitis macroura_ Lichtenstein, Darstellung Säugethier, pl. 46, with accompanying text, 1832. _Type locality._--Mountains northwest of the City of Mexico. _Range._--Southern half of Mexican Plateau and south to Guatemala. See figure 1. Marginal occurrences (all from Howell, N. Amer. Fauna, 20:41, 42, 1901) are: _Tamaulipas_: Jaumave. _Veracruz_: Las Vigas; Jico; Orizaba. _Puebla_: Tehuacan. _Guatemala_: Dueñas (vicinity). _Oaxaca_: 15 mi. W Oaxaca. _Colima_: Hacienda Magdalena. _Jalisco_: San Sebastian. _Tepic_: Santa Teresa. _Zacatecas_: Valpariso. _Characters._--Skull of medium size (basal length, [Male] 56, [Female] 54); tail averaging shorter than head and body. #Mephitis macroura vittata# Lichtenstein 1832. _Mephitis vittata_ Lichtenstein, Darstellung Säugethier, pl. 47, with accompanying text, 1832. 1901. _Mephitis macroura vittata_, Allen, Bull. Amer. Mus. Nat. Hist., 14:334, November 12, 1901. _Type locality._--"San Matteo el Mar" [= San Mateo del Mar], Oaxaca. _Range._--Known only from the type locality. See figure 1. _Characters._--Skull short ([Male] 54.6, [Female] 52.3); narrow across mastoid processes; tail long; body short. #Mephitis macroura eximius# new subspecies _Type._--Female, adult, skin with skull, No. 19272, Mus. Nat. Hist., Univ. Kansas; 15 kilometers west of Piedras Negras, 300 feet elevation, Veracruz, Mexico; 13 January 1947; obtained by J. Mazza and Walter W. Dalquest; original No. 7017, W. W. Dalquest. _Range._--From the vicinity of the type locality on the arid coastal plain of the lowlands of central Veracruz. See figure 1. _Diagnosis._--Size small (see measurements); tail long, ranging from 110 to 133 percent of length of head and body; color black, with white areas containing a few black hairs, and in non-hooded phase with white lateral stripes low on sides of body and in some specimens almost absent; skull small but broad across mastoid processes. _Comparisons._--From _Mephitis macroura macroura_ of the southern part of the Mexican Plateau, _M. m. eximius_ differs in shorter head and body, relatively (to body) longer tail, and smaller skull. From _Mephitis macroura vittata_ of the tropical lowlands of the Pacific slope of Oaxaca, _M. m. eximius_ differs in slightly larger average size throughout and relatively longer tail. [Illustration: FIG. 1. Map showing the geographic ranges of the four subspecies of the species _Mephitis macroura_.] _Remarks._--_M. m. eximius_ is regarded as a subspecies of _M. macroura_ because there is some overlap in size between larger individuals of _M. m. eximius_ and smaller individuals of _M. m. macroura_. Actually, as indicated above, we doubt that the geographic ranges of the two subspecies are continuous or that the geographic range of _M. m. eximius_ is continuous with the geographic range of _M. m. vittata_. Small size and relatively long tail characterize both of the lowland, tropical subspecies, _eximius_ and _vittata_, whereas the two upland subspecies of the temperate areas are larger and have relatively shorter tails. Habitat closely resembling that at the type locality extends from the southern base of the first mountains north of Jalapa southward as far as the north base of the Tuxtla Mountains--a distance of approximately 110 miles from northwest to southeast along the gulf coast. None of our 5 skins shows the hooded color-pattern so common on the Mexican Plateau and in _vittata_ of Oaxaca. One of our five specimens has well-developed lateral stripes; three have greatly reduced lateral stripes and one is black except for a white spot on the right hip. _Measurements._--An adult male (University of Kansas Museum of Natural History Catalogue Number, 17900), a subadult male (19273), and adult female (19272, the holotype) and a subadult female (19902), measure, in millimeters, respectively, as follows: Total length, --, 599, 578, 583; length of tail, --, 319, 335, 305; length of hind foot, 58, 62, 58, 60; basal length of skull, 56.1, 55.0, 52.8, 53.1; basilar length of Hensel, 53.6, 52.6, 50.3, 51.2; greatest zygomatic breadth, 41.6, 38.0, 39.0, 37.0; greatest mastoid breadth, 34.6, 34.3, 33.3, 31.5; breadth across postorbital processes, 22.2, 20.2, 20.5, 21.0; least interorbital breadth, 20.3, 18.2, 19.0, 18.5; palatal length, 24.2, 25.1, 24.2, 24.0; postpalatal length, 31.5, 29.6, 28.8, 29.0; foramen magnum to plane of last molars, 30.8, 29.4, 27.5, 29.0. _Specimens examined._--Total number, 5, all from Veracruz, Mexico, as follows: Rió Blanco, 20 km. WNW Piedras Negras, 3; 15 km. W Piedras Negras, 300 ft., 2. _University of Kansas Museum of Natural History, Lawrence, Kansas._ _Transmitted October 31, 1949._ 23-1544 --- Provided by LoyalBooks.com ---