A new bat from Mexico

VOL._XVIII, PP.

247-248 DECEMBER

_9, 1905

PROCEEDINGS

OF THE

BIOLOGICAL SOCIETY OF WASHINGTON

A NEW BAT FROM MEXICO.

BY WALTER

L.

HAHN.

A _study

of the

bat genus Hemiderma, begun by ^{the author} some time

_since,

has been delayed

^{in various}

ways, and

it

now becomes _necessary

to

publish

^a

preliminary

description ^ofa

new

species

from Mexico. For

the use of

the specimens on which

thisdescription ^is

based

the writer is

indebted

to

Dr.

C.

Hart Merriam, ^Chief

^ofthe Biological

Survey.

Hemiderma subrufum

_sp.nov.

Type from SantaIfigenia, Oaxaca, Mexico. No._75,127, U.S.National

Museum,

Biological SurveyCollection, cT adult. July 29, 1895. E.

W.

Nelson

and

E. A.

Goldman.

Original

number

8235.

Generalcharacters Size small (forearm under_40); furwith a decided reddish tinge^{; skull} short

and

smallwith high strongly rounded brain- case; teethsmall

and

toothrowsstrongly divergentposteriorly.

Color.

Ten

skinsfromthetypelocalityareuniformly^{of a}dark reddish

brown

colorabove.

The

individualhairsare

banded

asfollows:

A

_very

short (not over

mm.)

^{basalareawhitish;nextawider}

band

ofdark_(near the clove

brown

ofRidgway)

which

isfollowed

by

^another

and

wider

band

ofbuffishwhite; succeeding^thisisthe

somewhat

narrower

band

ofreddish prout'sbr.own

which

_givestotheanimalitscharacteristiccolor_; hairs

mi

nutely tippedwithwhitish. Underparts^similar; butthebandsofcolorless sharply

marked

off,thedark bands _beingreduced

and

the pale areas suf fused,

making

the general^colorpaler

and

duller.

Fur and Membranes.

The

_fur, as

compared

^{with other}specimens^ofthe genus from Mexico,^isshort

and

_sparse,

and

the

membranes more

brownish.

53 PROC. BIOL. Soc. WASH., VOL. XVIII, ^1905. (247)

248 Hahn A New Bat From

Mexico.

Interfemoral

membrane

sparsely furred ^{at base.}

Wing ^membranes

^from

theankle_directlyopposite the^calcar.

Skull

and

Teeth.

The

skullissmallwitha shortbroad _rostrum,

and

_high, stronglyroundedbraincase.

The

_palate iswideposteriorly,narrowed an teriorly; posterior palatalprojection short

and

broad. Auditalbullsesmall;

basisphenioid pitsdeep.

The

teeth are small

and

thetoothrows_short,that portionbehindthe anteriorpremolar being^sostronglydivergent^{as to}form anoticeable anglewiththelineofthe anterior_portion.

Measurements.

Type

^:* Forearm,³⁹;hind_foot,13; calcar, 7; ear from base, 16; earfrom _{notch, 13;} noseleaf without horse shoe,^6.5. Skull of type: Greatestlength, 21; basal length,16.5; greatestbreadth,11; greatest depth,^9.5, interorbitalbreadth,⁵; uppertoothrow, ^7.

Remarks.

Hemiderma

_subrufum is awell

marked

form

which

doesnot appear^tointergradewith

any

^other

known

_species. Insizeitisinterme diatebetweenthe

Hemiderma

castaneum ofH.Allen

and

the_large

Mexican

species called nzteca

by

Saussure.f

The body

^issmall

and

thelimbsslender

and

short (forearm 39^as

compared

^with42 given

by

Saussure). ^Italso differs

markedly

^{in cranialcharactersfrom}azteca,theskullbeing^notonly^shorter

and

smaller but of a verydifferent aspect,the braincase _rising abruptly above thelevelofthe rostrum,^itssides flaringont ina broadly rounded arch

and

the_palate

and

rostrum beingrelatively

much

broader.

The

teeth alsoare

much

_lighter; thetoothrowisshorter

by

a millimeter

and

therela tiveproportions of the cusps of

some

ofthe teethdiffermarkedly.

Inadditiontothetype^seriesfrom Oaxaca,^I

have examined

_specimens inthecollectionofthe Field

Columbian Museum

from _Achotal,

Vera

Cruz,

which

do not appear to differ in

any

^essential

way

^{from the} type.

The

colorisperhaps^alittlepalerbutthisisan extremely^variablecharacter in thisgenus,ⁱⁿ

which

distinctdichromatismexists.

*Measurementstakenfrom dry^skin.

t Carollia azteca Saussure,Rev. et Mag.de ^Zool.1860, p. 480. Temperate and trop icalMexico.