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) publishedtheir revisionary account of American bats of the genus _Myotis_, theblack myotis, _Myotis nigricans_, was known no farther north thanChiapas and Campeche. Collections of mammals made in recent years forthe Museum of Natural History of The University of Kansas includespecimens of _M. Nigricans_ from eastern Mexico as far north asTamaulipas. Critical study of this newly acquired material reveals thatit pertains to an hitherto unnamed subspecies that may be named anddescribed as follows:

MYOTIS NIGRICANS DALQUESTI new subspecies

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

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

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

_Comparison. _--Color almost as in _Myotis nigricans extremus_, thesubspecies occurring adjacent to _dalquesti_ in Chiapas and Tabasco. From _M. N. Extremus_, _dalquesti_ differs as follows: larger; hypoconein M1 and M2 broader making posterointernal part less rounded;protostyle of P4 prominent instead of absent; P3 in line with C and P2instead of displaced lingually; sagittal crest absent instead of presentposteriorly. _Myotis nigricans nigricans_ and _M. N. Dalquesti_ are ofapproximately equal size; otherwise they differ in the same features asdo _extremus_ and _dalquesti_. 

_Measurements. _--Average and extreme measurements of seven males fromthe type locality, followed by those of 19 females from 38 km. SE JesúsCarranza, and finally length of forearm and cranial measurements ofeight female topotypes of _M. N. Extremus_, are as follows: Totallength, 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 (includingincisors), 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 bemeasured); 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 sagittalcrest), 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 breadthat 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, andpremolars × 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 ofProf. Walter W. Dalquest who gathered the largest and most variedcollection of mammals ever taken in the state of Veracruz. 

Inspection of the measurements given above will reveal that there is nooverlap between _extremus_ and _dalquesti_ in the interorbitalconstriction or occipital depth and only slight overlap in the length ofthe maxillary tooth-row and maxillary breadth. 

In 10 adult females from Ocosingo, Chiapas, there is suggestion ofintergradation between _dalquesti_ and _extremus_ in that one specimen(66515 KU) has the cranial characters of _extremus_ except that it islarge like _dalquesti_; in two other skulls P3 is slightly displacedlingually and two other skulls bear a slight sagittal crest. These arefeatures 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 anddiffer 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