

















     UNIVERSITY OF KANSAS PUBLICATIONS

         MUSEUM OF NATURAL HISTORY

    Volume 14, No. 4, pp. 69-72, 1 fig.
             December 29, 1961


 A New Subspecies of the Black Myotis (Bat)
            From Eastern Mexico

                     BY

     E. RAYMOND HALL AND TICUL ALVAREZ


            UNIVERSITY OF KANSAS
                  LAWRENCE
                    1961




 UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY

     Editors: E. Raymond Hall, Chairman, Henry S. Fitch,
                    Theodore H. Eaton, Jr.


             Volume 14, No. 4, pp. 69-72, 1 fig.
                 Published December 29, 1961


                     UNIVERSITY OF KANSAS
                       Lawrence, Kansas


                          PRINTED BY
               JEAN M. NEIBARGER, STATE PRINTER
                        TOPEKA, KANSAS
                             1961
                           [Device]
                           28-8477




A New Subspecies of the Black Myotis (Bat) From Eastern Mexico

BY

E. RAYMOND HALL AND TICUL ALVAREZ


In 1928 when Miller and Allen (Bull. U. S. Nat. Mus., 144) published
their revisionary account of American bats of the genus _Myotis_, the
black myotis, _Myotis nigricans_, was known no farther north than
Chiapas and Campeche. Collections of mammals made in recent years for
the Museum of Natural History of The University of Kansas include
specimens of _M. nigricans_ from eastern Mexico as far north as
Tamaulipas. Critical study of this newly acquired material reveals that
it pertains to an hitherto unnamed subspecies that may be named and
described as follows:


MYOTIS NIGRICANS DALQUESTI new subspecies

_Type._--Male, adult, skin and skull, No. 23839 Museum of Natural
History, University of Kansas; from 3 km. E of San Andrés Tuxtla, 1000
ft., Veracruz; obtained on January 5, 1948, by Walter W. Dalquest,
original No. 8444.

_Range._--Tropical Life-zone of eastern México from southern Tamaulipas
to central Chiapas.

_Diagnosis._--Color black or dark brown, venter having brownish wash;
size large (see measurements); M1 and M2 quadrangular; prominent
protostyle on P4; P2 and P3 in straight line; sagittal crest absent.

_Comparison._--Color almost as in _Myotis nigricans extremus_, the
subspecies occurring adjacent to _dalquesti_ in Chiapas and Tabasco.
From _M. n. extremus_, _dalquesti_ differs as follows: larger; hypocone
in M1 and M2 broader making posterointernal part less rounded;
protostyle of P4 prominent instead of absent; P3 in line with C and P2
instead of displaced lingually; sagittal crest absent instead of present
posteriorly. _Myotis nigricans nigricans_ and _M. n. dalquesti_ are of
approximately equal size; otherwise they differ in the same features as
do _extremus_ and _dalquesti_.

_Measurements._--Average and extreme measurements of seven males from
the type locality, followed by those of 19 females from 38 km. SE Jesús
Carranza, and finally length of forearm and cranial measurements of
eight female topotypes of _M. n. extremus_, are as follows: Total
length, 80 (77-82), 76 (72-80); length of tail, 32.8 (30-35), 33.5
(31-35); hind foot, 7.9 (7-8), 8.0 (8-8); forearm, 34.2 (33.6-35.3),
35.1 (33.1-36.4), 33.1 (31.8-34.3); greatest length of skull (including
incisors), 13.8 (13.3-14.1), 13.6 (13.2-14.1), 12.9 (12.6-13.1);
zygomatic breadth, 8.1 (7.9-8.4), 8.1 (7.9-8.3), 8.0 (only one can be
measured); width of rostrum above canines, 3.2 (3.1-3.3), 3.2 (3.0-3.4),
3.1 (3.0-3.2); interorbital constriction, 3.6 (3.5-3.7), 3.6 (3.5-3.8),
3.4 (3.3-3.4); occipital depth (excluding auditory bullae and sagittal
crest), 4.6 (4.4-4.8), 4.6 (4.3-4.9), 4.3 (4.1-4.6); maxillary tooth-row
(C-M3), 5.0 (4.8-5.1), 5.0 (4.8-5.2), 4.7 (4.6-4.8); maxillary breadth
at M3, 5.2 (5.1-5.4), 5.3 (5.1-5.5), 5.1 (4.8-5.2).

[Illustration: FIG. 1. Left side of skull, incisors, canine, and
premolars × 11, and occlusal surface of left first upper molar × 20. A.
_Myotis nigricans dalquesti_, holotype. B. _Myotis nigricans extremus_
No. 77674 USNM, topotype.]

_Remarks._--The subspecific name _dalquesti_ is given in recognition of
Prof. Walter W. Dalquest who gathered the largest and most varied
collection of mammals ever taken in the state of Veracruz.

Inspection of the measurements given above will reveal that there is no
overlap between _extremus_ and _dalquesti_ in the interorbital
constriction or occipital depth and only slight overlap in the length of
the maxillary tooth-row and maxillary breadth.

In 10 adult females from Ocosingo, Chiapas, there is suggestion of
intergradation between _dalquesti_ and _extremus_ in that one specimen
(66515 KU) has the cranial characters of _extremus_ except that it is
large like _dalquesti_; in two other skulls P3 is slightly displaced
lingually and two other skulls bear a slight sagittal crest. These are
features characterizing _extremus_. Otherwise the specimens resemble
_dalquesti_, to which subspecies they are here referred.

Three males from a place 8 km. W and 10 km. N El Encino, 400 ft.,
Tamaulipas, are the northernmost representatives of the species and
differ from the other specimens of _dalquesti_ in shorter forearm,
shorter maxillary tooth-row and lesser maxillary breadth.

    Study in the laboratory was supported by Grant No. 56 G 103 from the
    National Science Foundation. Field work was supported by a grant
    from the Kansas University Endowment Association. We thank Dr. David
    H. Johnson for lending eight topotypes of _M. n. extremus_. Other
    specimens of _extremus_ available to us are as follows: 1 mi. E
    Teapa, Tabasco, 1 (7535 LSU--courtesy of Dr. George H. Lowery, Jr.);
    Cayo Dist. Augustine, British Honduras, 1 (9670 KU, in red phase);
    12 km. NNW Chinajá, Guatemala, 4.

    _Specimens examined._--Total, 142, as follows: Tamaulipas: 8 km. W,
    10 km. N El Encino, 400 ft., 5. Veracruz: 4 km. WNW Fortín, 3200
    ft., 1; 2 km. N Motzorongo, 1500 ft., 1; 3 km. E San Andrés Tuxtla,
    1000 ft., 7; 38 km. SE Jesús Carranza, 500 ft., 118. Chiapas:
    Ocosingo, 10.

    _Transmitted June 30, 1961._

                               28-8477






