University of Kansas Publications

Museum of Natural History

Volume 7, No. 14, pp. 613-618

June 10, 1955

Taxonomy and Distribution

of Some American Shrews

BY

JAMES S. FINDLEY

University of Kansas

Lawrence

1955

University of Kansas Publications, Museum of Natural History



Editors: E. Raymond Hall, Chairman, A. Byron Leonard,

Robert W. Wilson



Volume 7, No. 14, pp. 613-618

Published June 10, 1955

University of Kansas

Lawrence, Kansas

PRINTED BY

FERD VOILAND, JR., STATE PRINTER

TOPEKA, KANSAS

1955


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Taxonomy and Distribution

of Some American Shrews

by James S. Findley

Sorex cinereus ohionensis Bole and Moulthrop.—In their description of
this subspecies from Ohio, Bole and Moulthrop (1942:89-95) made no
mention of specimens in the United States Biological Surveys Collection
from Ellsworth and Milford Center, Ohio, which stand in the literature
(see Jackson, 1928:49) as Sorex cinereus cinereus. These two
localities lie south of the geographic range ascribed to S. c.
ohionensis by Bole and Moulthrop. Examination of the two specimens,
United States Biological Surveys Collection, Catalogue No. 70566, and
United States National Museum, No. 19434, respectively, both of which
are alcoholics, reveals that they are referable to the subspecies
ohionensis rather than to S. c. cinereus. This reference is made on
the basis of small size, short tail (33 and 31 millimeters,
respectively), and fourth upper unicuspid as large as third (the
specimen from Milford Center lacks the skull). The occurrence at Milford
Center provides a southward extension of known range for S. c.
ohionensis of approximately 70 miles. S. c. cinereus seems not to
occur in Ohio.

Cryptotis micrura (Tomes).—Davis (1944:376) assigned a Cryptotis
from Boca del Río, Veracruz, to Cryptotis parva berlandieri (Baird).
Comparison of this specimen, Texas Cooperative Wildlife Collections, No.
2765, with 8 specimens of C. micrura from various parts of northern
Veracruz and with 9 C. parva from southern Tamaulipas reveals that the
shrew from Boca del Río is referable to Cryptotis micrura. The series
of 8 specimens in the University of Kansas Museum of Natural History
from Altamira, Tamaulipas, provides the southernmost known record of
Cryptotis parva berlandieri. These 8 specimens are typical of C. p.
berlandieri and show no approach to C. micrura. Average and extreme
cranial measurements of 7 specimens from 1 mi. S Altamira are:
condylobasal length, 15.6 (15.2-16.1); palatal length, 6.6 (6.4-6.7);
maxillary tooth-row, 5.7 (5.4-5.8); cranial breadth, 7.6 (7.4-8.0);
least interorbital breadth, 3.5 (3.4-3.7); maxillary breadth, 5.0
(4.8-5.2). Cranial measurements of 8 specimens of C. micrura[Pg 616] from
various localities in northern Veracruz (1 km. E Mecayucan, 1; 7 km. NNW
Cerro Gordo, 3; Teocelo, 2; 7 km. W El Brinco, 1; 5 km. N Jalapa, 1)
are: condylobasal length, 17.1 (16.6-17.4); palatal length, 7.1
(6.9-7.4); maxillary tooth-row, 6.2 (5.9-6.4); cranial breadth, 8.5
(8.3-8.6); least interorbital breadth, 3.7 (3.6-4.1); maxillary breadth,
5.3 (5.1-5.6). C. parva and C. micrura may intergrade but a distance
of 140 miles separates the geographic ranges as now known of the two
kinds and every specimen examined by me is clearly referable to one or
the other of the two named kinds and shows no evidence of
intergradation.

Notiosorex crawfordi crawfordi Baird.—A specimen in the Museum of
Natural History from Jaumave, and one from Palmillas, Tamaulipas,
collected by Gerd Heinrich, provide records of the easternmost margin of
the range of this species in Mexico. Assignment is made to the
subspecies crawfordi on geographic grounds. The two specimens differ
from a male from 13 mi. S and 15 mi. W Guadalajara, Jalisco, referred
(Twente and Baker, 1951:121) to N. c. evotis (Coues) in slightly
larger size; however two skulls from owl pellets from 21 mi. SW
Guadalajara, also referred to evotis (loc. cit.), seem to me to
differ in no important way from skulls of the Tamaulipan specimens.
Measurements of the Tamaulipan specimens, both females, 54932 KU and
54933 KU, are respectively: condylobasal length, —, 16.7; palatal
length, —, 7.2; maxillary tooth-row, 6.6, 6.1; cranial breadth, 8.3,
8.1; least interorbital breadth, —, 3.5; maxillary breadth, —, 5.1;
total length, 90, 90; tail, 28, 30; hind foot, 11.0, 11.5; ear, 8, 8.

The only other eastern Mexican record of N. crawfordi is based on two
skulls from owl pellets collected 3 mi. NW Cuatro Cienegas, Coahuila
(Baker, 1953:253).

Sorex oreopolus emarginatus Jackson.—A first-year female Sorex, KU
54346, obtained by Rollin H. Baker from 7 mi. SW Las Adjuntas, 8900 ft.,
Durango, seems closest, among Mexican shrews that I have examined, to
two specimens of S. emarginatus from Plateado, 7600 to 8500 ft.,
Zacatecas. Measurements of the Las Adjuntas specimen are: total length,
88; tail, 39; hind foot, 13; palatal length, 7.2; maxillary tooth-row,
6.4; maxillary breadth, 4.9; least interorbital breadth, 3.6.

Sorex emarginatus previously was known only from Plateado and the type
locality, Bolanos, Jalisco. Comparison of these three specimens with
specimens of other species of Mexican shrews of the S. saussurei group
leads me to conclude that the group contains[Pg 617] two species rather than
four as was previously thought. Sorex emarginatus, S. ventralis, and
S. oreopolus seem to me to be conspecific. All three nominal species
are relatively small, short-tailed shrews. The skulls of the three kinds
resemble one another in relatively short rostrum and in dental details.
Slight differences in cranial proportions differentiate the three and
they should, until more specimens of each are obtained and studied,
retain subspecific rank. The specific name, Sorex oreopolus Merriam
1892, should apply to the three kinds since it antedates the names
ventralis and emarginatus. The two names last given, therefore,
should stand as Sorex oreopolus ventralis Merriam and Sorex oreopolus
emarginatus Jackson. The two species, the large S. saussurei, and the
small S. oreopolus, as the latter is here understood, occur together
over an extensive region in southern Mexico. In other parts of North
America a large and a small species of Sorex often occur together in a
given area.

The Las Adjuntas specimen was taken only 10 miles southwest of El Salto,
Durango, the type locality of S. durangae Jackson. Jackson (1928:101)
placed durangae in the Sorex vagrans-obscurus species group, but the
two specimens available to him were second year adults with the teeth so
much worn that diagnostic characters are not visible on them. I have
examined these two specimens (United States Biological Surveys
Collection 94539 and 94540) and find that in bodily and cranial
proportions they resemble Sorex s. saussurei, and I so assign them.

Sorex milleri Jackson.—Koestner (1941:10) reported 5 Sorex from
Cerro Potosí, near La Jolla, Municipio de Galeana, Nuevo Leon, as Sorex
emarginatus. Comparison of 4 of these specimens (Chicago Museum of
Natural History, 48227, 48228, 48229, 48230) with two S. emarginatus
from Plateado, Zacatecas, and specimens of other species of Sorex
indicates that the Cerro Potosí shrews differ in many features from
emarginatus, but closely resemble, in size and cranial characters, a
specimen (F. W. Miller, No. 20) of S. milleri from Sierra del Carmen,
Coahuila, and seems to be referable to that species which was not named
when Koestner (loc. cit.) recorded his specimen. The range of S.
milleri is therefore extended southwestward to western central Nuevo
Leon.

Comparison of S. milleri with specimens of other species of North
American Sorex leads me to conclude that S. milleri is most closely
related to S. cinereus Kerr, and should be included in the S.
cinereus group rather than in the S. vagrans-obscurus group.[Pg 618] Sorex
cinereus and S. milleri are alike, and both differ from even the
smallest S. vagrans in relatively long and narrow rostrum, narrow
teeth, smaller skull, and in having the third upper unicuspid more often
equal to or smaller than, rather than larger than, the fourth unicuspid.

I judge S. milleri to be a relict population of S. cinereus,
isolated in the mountains of northeastern Mexico, probably in the late
Pleistocene. Sorex cinereus reported from Pleistocene deposits in San
Josecito Cave, Nuevo Leon (Findley, 1953:635), probably represents a
population ancestral to the modern S. milleri. Sorex milleri should
retain specific status because of constant cranial differences from S.
cinereus, particularly relatively broader rostrum.

LITERATURE CITED

Baker, R. H.

Bole, B. P., and P. N. Moulthrop.

Davis, W. B.

Findley, J. S.

Jackson, H. H. T.

Koestner, E. J.

Twente, J. H., and R. H. Baker.

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