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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
[576]
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
[577]
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
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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 (♂ 60 mm, ♀ 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, ♂ 56, ♀ 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 (♂ 54.6, ♀ 52.3); narrow across mastoid processes;
tail long; body short.
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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.
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
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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.