Two New Moles (Genus Scalopus)

from Mexico and Texas

BY


ROLLIN H. BAKER





University of Kansas Publications

Museum of Natural History



Volume 5, No. 2, pp. 17-24

February 28, 1951



University of Kansas

LAWRENCE

1951

University of Kansas Publications, Museum of Natural History



Editors: E. Raymond Hall, Chairman, Edward H. Taylor,

A. Byron Leonard, Robert W. Wilson



Volume 5, No. 2, pp. 17-24

February 28, 1951




University of Kansas

Lawrence, Kansas





PRINTED BY

FERD VOILAND, JR., STATE PRINTER

TOPEKA, KANSAS

1951



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[Pg 19]

Two New Moles (Genus Scalopus)

from Mexico and Texas

BY



ROLLIN H. BAKER

In the spring of 1950, a field party from the University of Kansas
Museum of Natural History including J. R. Alcorn, W. J. Schaldach,
Jr., George Newton, and the author collected mammals in the
Mexican state of Coahuila. A few days were spent in the Sierra del
Carmen. One morning when examining sets for pocket gophers in
these mountains, Alcorn found a mole caught in one of the traps.
Subsequent examination discloses that this specimen belongs to a
heretofore unknown species which may be named and described as
follows:

Scalopus montanus new species

Remarks.—S. montanus is known from a single specimen, which
represents the second known occurrence of the genus Scalopus in[Pg 20]
Mexico. The other occurrence is that of S. inflatus in the state of
Tamaulipas. S. montanus is geographically isolated in mountainous
country from other species of Scalopus. Ten of the recognized subspecies
of S. aquaticus were available for examination and descriptions
of others were studied. It was found that the number and
magnitude of the differences separating any one of these subspecies
from an adjoining one was less than those separating S. montanus
from S. a. texanus and S. a. intermedius, which are, geographically,
closest to S. montanus. S. montanus seems not to be closely related
to S. inflatus of Tamaulipas. S. montanus is given specific rank
because of the great degree of difference between it and its nearest
relatives, and because of its geographically isolated position.

The specimen of S. montanus was taken in a tunnel found by digging
away a mound thought to be that of the pocket gopher,
Thomomys sturgisi. A trap set in one direction in the tunnel caught
the mole; a trap set in the other direction in the tunnel was later
covered with soil, evidently by a gopher. After the capture a
thorough inspection of the area revealed no "raised" tunnels, typical
of Scalopus. A series of Thomomys was taken in this area in sets
placed in tunnels found under similar mounds. This locality was
near the headquarters of the Club Sierra del Carmen in a parklike
stand of oak timber in a cañon, at an elevation of 4950 ft. as
recorded by our altimeter. The plant association was judged to be
characteristic of the Upper Sonoran Life-zone, not far below the beginning
of the Transition Life-zone. The area was heavily grazed
by goats, hogs and horses and had little grass or other ground cover
under the trees. The soil in this cañon was not deep and consisted
of a rocky, marly mixture, pale red in color, evidently produced by
weathering of the reddish volcanic rocks bordering the cañon.

The Sierra del Carmen is a high, igneous range, surrounded for
the most part by Lower Sonoran plains and desert. Zoologically,
these mountains are poorly known. Few collectors have been in
the area; most of these have been afforded accommodations through
the Club Sierra del Carmen (Carmen Mountain Hunting Club), the
members of which have been especially interested in assisting
naturalists. Several kinds of mammals are known only from this
"biological island" including the pocket gopher mentioned above
and the shrew, Sorex milleri. The finding of a mole in the higher
elevations of this range suggests that moles may occur in other
mountainous areas of Mexico.[Pg 21]

Assistance with field work is acknowledged from the Kansas University
Endowment Association.

In studying Scalopus aquaticus texanus, I noted that Allen (Bull.
Amer. Mus. Nat. Hist., 3:221, April 29, 1891) based the original description
on a single, unsexed specimen taken in Presidio County,
Texas, by Wm. Lloyd in September, 1887. Later, Allen wrote (Bull.
Amer. Mus. Nat. Hist., 5:200, August 18, 1893) that a series of moles
from Rockport, Aransas County, Texas, agreed essentially with the
type. True (Proc. U. S. Nat. Mus., 19:22, December 21, 1896)
believed that the type was actually from Aransas County rather than
Presidio County. This belief was shared by later workers. In
checking the literature, I find that the collector of the type, Wm.
Lloyd, who was obtaining specimens for George B. Sennett at the
time, took other mammals in September as well as in October of
1887 in Presidio County (see Allen, Bull. Amer. Mus. Nat. Hist.,
3:221, 223, 224, April 29, 1891) and birds there in June of 1887 (see
Sennett, Auk, 5:43, January, 1888). I can find no evidence that
Lloyd collected in or near Aransas County in 1887 and see no reason
for doubting that the locality, Presidio County, as written on the
original label of the type of S. a. texanus is correct. Mr. M. J. Carroll
of the Texas State Historical Association advises me that in 1887,
Presidio County was reduced to its present size by the creation of
Brewster and Jeff Davis counties. Lloyd might have taken the mole
in any one of these three Trans-Pecos counties. Even so, these
counties are widely separated geographically from the range of other
moles designated as S. a. texanus (see Davis, Amer. Midl. Nat.,
27:386, March, 1942). The taking of S. montanus in the Sierra del
Carmen immediately south of Trans-Pecos Texas leads me to think
that Lloyd's mole might have been taken in a mountainous region
within one of the three counties mentioned above. A description of
Scalopus aquaticus texanus Allen follows:

Scalopus aquaticus texanus Allen

Remarks.—The type has been previously examined by True
(op. cit.:44). The skin is faded and of little taxonomic worth. The
anterior part of the skull is present along with both upper tooth-rows
and most of the lower jaws. The teeth are well worn, indicative of
old adulthood. In size, S. a. texanus appears closest to moles from
southern Texas (Rockport) which previously were assigned to the
subspecies Scalopus aquaticus texanus. The tooth-rows are of the
same length, but the individual teeth of S. a. texanus are significantly
larger.

The moles in southern Texas previously ascribed to Scalopus
aquaticus texanus seem to be without a name and may be known as
follows:

Scalopus aquaticus alleni new subspecies

[Pg 23]

Remarks.—This mole is named in honor of Dr. J. A. Allen in
recognition for his work on Texas mammals. Grateful acknowledgment
is made to those in charge of the collection of Recent mammals
in the American Museum of Natural History for permitting me to
examine the moles from Aransas County and the type specimen of
Scalops argentatus texanus Allen.

Transmitted January 15, 1951.

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