Karyotypes of selected bats (order Chiroptera)

Item Type text; Thesis-Reproduction (electronic)

Authors Osborne, Jerry Lee, 1940-

Publisher The University of Arizona.

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KARYOTYPES OF SELECTED BATS

(ORDER CPHROPTERA)

by

Jerry Lee Osborne

A Thesis Submitted to the Faculty of the

DEPARTMENT OF ZOOLOGY

In Partial Fulfillm ent of the Requirements For the Degree of

MASTER OF SCIENCE

In the Graduate College

THE UNIVERSITY OF ARIZONA

1965

STATEMENT BT AUTHOR

This th esis has been submitted in p artia l fu lfillm en t of requirements for an advanced degree a t the University of Arizona and is deposited in the University Library to be made available to borrowers under rules, of the Library,

Brief quotations from th is th esis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of th is manuscript in whole or in part may be granted by the head of the major department' or the Dean of the Graduate College when in h is judgment the proposed use of the material i s in the in terests of scholarship. In a l l other instances, however, permission must be obtained from the author.

SIGNED

APPROVAL BT THESIS DIRECTOR

This th esis has been approved on the date shown below g

’ E, L» CQCKRTM Professor of Zoology

Acknowledgments

Various people have helped in the preparation of th is th e s is .

My particular thanks go to Dr. E, L. Cockrum for his many suggestions,

comments, and critic ism s. I acknowledge with deep appreciation Dr.

¥ . J. McCauley who read the manuscripts and gave me the benefit of much

needed constructive criticism and Dr. ¥. R. Ferris for his suggestions

and the use of much of the equipment needed for th is study.

I gratefully acknowledge my fellow graduate students who have

helped me in obtaining the animals used in th is study and a special

note of thanks is given to Jerry Nagle and his w ife, Sa lly , for their

constant encouragement and assistance in preparing th is th esis . I am

grateful to Jim Patton for his assistance and his knowledge of the

technique used in th is study. I wish to thank Ruth Darden for her

help in the preparation of the illu stra tio n s .

To my w ife, Marilyn, I give my very deep appreciation and

thanks for without her help th is thesis would not have been possible.

i i i

Table of Contents

Page

Xjlst of Tables 9 qooooooooooossooop^oooooooooooooooooooooo l i s t 0,f P lates OOOOCtSOOPOt&OOPOOO POOOOOOOQpOPOOOOOOOPOO'O * vlx

L ist Of PlgUi^eS o o t a a o t i a o o e o o i ^ d d o p d ^ o o p p O i d O O O b O i d O i p o d p o o o t i VXlX

Abstract o o o o o o o o o o o p e o o p o o o o o o ^ p o o o ^ o o o d o o o e o o p o o o o o o c 1%

Introduction o o o o o o p o o o o o o o p e o o p d o p p ^ o o a o o o o o o o o o o o o o o o o 1

M aterials and Methods o o o p o o p p o o o o o p a o o o o o p o o o o o p o o o o o o o o 3

P e S U l l t S o o o o o o o o o p o o o p & o o o o o o o o o o o o o o o p p o a o o c ' o c p o o d o o o 7 "

Pteronotus da^yi o o o o o d p © c p p p e e 6 o o » o e o o o o o e » p p e o p » TMacrotus /wa te r honsli d © o o e d o © © p o o d o © © o o o e o A o e o © o o o d yChoerongotera£ Bie^cxcanns o < ) © o o < > ' © o p o o o o o t > o c t o © o © © o p o © ^LeptonyeterIs nxvalxs o o d p o o © i ! > p o © o p © o © o o o £ j o o c ? o o < ? © o o 10Myotis thysanodes o p o o o © © o o t s d o o p o © © o o o o © o p © « ® o o e o © 10MyotXS VO lanS o o o p o o d o o o p o o o o a o p o o d o o o © o © o o o © © o o o o 11Myotis fo rtidens © o © G < s e © < i i o © o & o © o o © © o © © © o o © o © © o a o o o 12Pl^onpc VlVeSl o o O ' £ > o a o o © © o p p | © p © © © ' ( > o e o o © P © « > o o o © © © . o i i j 1 2

P ip is tre l ln s hesperns © o o o © © © © © © © © © © © © © © © © © © © © © © © © © 13Eptesicus fnscns © © © © o © © » © © © © © © © © © © o © o © © © © < s i o © © © o o © liila s lu m s cine reus © © © © © © © © © © © © © © © © © © © © © © © © © © © © © o o © llj,L aslonycteris noctxvagans © © © © © © © © © © © o © © © © © © © © © © © © © ® 13Tadarida bras H ie ns is © © © © © < & © © © © © © © © © o o o © © © © © © © © © © * © 16Tadarlaa fetnorosacca © o © o o o o © o © o o o © © © © o 9 o © o o o © o © o © o 16

Discussion ©©©©©©©©©©©©©©©©©©©©©©©©©©©©©©ooo©©©©©©©©©©© 13

Mechanisms of Chromosomal Evolution Affectingthe Karyotype ©©©©©©©©©©©o©©©©©©©©©©©©©©©©©©©©©© 18

; Fusion and Fragmentation (Robertsonian Ifariatiori) © 18Non-Robertsonian Variation ©©©©©©oo©©©©©©©©©©©© 18Polyploidy and Polyson^ ©a©.©©©.©©©©©©©*©©©©** 19

Interpreting Data Derived From Karyotypes o©©©oo©©©©o©© 19Evolutionary Trends and Relationships

Within the Family Vespertilionidae o©o©ooo©®oo©©©©©® 23Cytological Evidence Suggests the Taxonomic ..^Revision of Pisonyx vivas i 0 » o 00 ©6oo©©©©o©ooo 25

iv

Table of Contents (continued)

PageEvolutionary Trends and Relationships

Within the Family Molossidae 6 « o o e Q o b Qo < ? « o o e e 0 0 o o o 0 = 26 Evolutionary Trends and Relationships

Within the Family Phyllostomatidae o o o 0 0 o o 0 0 0 o o 0 0 0 = = a 27

Smmnary and Oonclusxons o o o e b o o b o b o o o b o o o o o o o e o o o o o b o t i o o o e 2^

Appendix A e o e o o o o e o o o o o o o o o o o e o o o o o o o o o o o o o o o e o o o o o o e o o 31

Appendix B o o o o o o e o o o o o e o o o o o o Q o e o o o b b o o o b e o o e ^ Q b o o o e o o o

AppendIX C o o o o o o o o o o o d o o o o o b o & o o o b o o o o o Q o o o o o o o t i o b o e e c y 53

L it e r a t u r e C ite d © © © © b o d o o o o a o o b o o o o e o o o o o o b o o o o o o e o e b o o b ' 5 5

L ist of Tables

Table Page

I . Summary of diploid numbers, autosomal types, sex chromosomes, and fundamental numbers of the species studied in the order C b i r o p t e r a 8

II . Summary of chromosome numbers and fundamentalnumbers in the Qhiroptera 21

III . Evolutionary trends in the family Yespertilionidaebased on d iploid and fundamental numbers. . . . . . . . . . . . . . . . . . . 2h

IV. Chromosome counts in the genus Pipis tre l lus . . . . . . . . . . . . . . . . 25

V, Evolutionary trends in the family Phyllostomatidaebased on diploid and fundamental n u m b e r s . . . . . . . . . . . . . . . . . . . 28

v i

L ist of Plates

Plate

1,

2 ,

3<>

li =

6.7.

8,

9.

10.11..12.

13.

111.

Representative male karyotype of Pteronotns davyi o »»o»=« 31

Representative female karyotype of Macrotuswaterhonsxi o e o e o o o o o o e . e o d O o o o o o o o o b d o o o t i o o o o o o . 32

Representative female karyotype of Choeronycterismexica nns © 0 * ^ 0 0 0 0 « o o © o o d d o d o o o o d o d o o d o d o o i » o o o o 33

Representative female karyotype of Leptonycterisn iva lis o o o e e o o e e o o d o e o o o o o o e o e o o o d o o d o o b o o o o o e 3l|

Representative male karyotype of Myotis thysanodes o 0 e o e o 35

Representative male karyotype of Myotis volans 0 0 o 0 o 0 0 0 0 36

Representative male karyotype of Myotis fortldens 0. . 0 . 0 = 37

Representative male karyotype of Pizonyx v iv esi 0 0 0 . 0 0 . . 38

Representative female karyotype of P ip istre llu shesperus o o o o o o o o o o o o © o d » o o e o « o o o o b o o o < i o o o « o o o o 39

Representative female karyotype of Eptesieua fuscus 0 0 0 = 0 Uo

Representative female karyotype of La slur us cinereus <,«= = J4.I

Representative male karyotype of Lasionycterisnoctivagans o = a o = e = o = = = a o e o s = « = = o = « = = = a o = « * « « ' » ' » ' » I 4 . 2

Representative female karyotype of 'Cadaridabrasiliensxs = = o = = o = = ooo = ooo = oo = = = = = = o = oo = = = o = o lt3

Representative female karyotype of Tadaridafemorosacoa oo = = = = o = o = = = = = o o = = = o o o = o = = o o @ = o = o o o = 11

v i i

L ist of Figures

Figure

I , Pteronotus davyig Photomicrograph of representative chromosome spread yo<»oooeooobi>ooeo»o<>ooooodoooooo

2° Macrotus waterhousiig Photomicrograph of representative chr omo so me s pr ead ob.ooooooooboboooobbObG)©ooooooa

3» Choeronycteris mexicanus: Photomicrograph of repre-sentative “chromosome spread <, a e 0 0 0 <, 0 0 <, 0 0 0 „ 0 e 0 0 a 0 0 „

he Leptonycteris n iva lis s Photomicrograph of representative chromosome spread 000000000000000000000000000000

' h, Myotis thysanodes g Photomicrograph of representativechromosome spread eooooooooooooooooooooooooooooo

60 Myotis voIanss Photomicrograph of representativechromosome spread ooooeooooooooooooooooooooooooo

7o Myptis fortidenss Photomicrograph of representativechromosome spread 00000000000000oooeoooooooeoooo

8, Piaonyx v iy e s ig Photomicrograph of representativechromosome spread 00 000 000000000000000 0000000000

9» P ip istrellus. hesperuss Photomicrograph of representative chromosome spread 0000000 00 *0000 0000 0000000000000

10o Eptesicus fuscus: Photomicrograph of representativechromosome spread ooooooooooooooooooooooeooooo.00

11o Laslurus cinereus s Photomicrograph of representativechromosome spread 00 000000000000 00000 ooooooooooo

12, Laslonycteris noctlvagans? Photomicrograph of repre-sentative chromosome spread oeo*«o«.oooo*o«o«ooo'»o

13, %darida b r a s ilie n s is% Photomicrograph of representative cEromosbme spread 0000 o 00000 0000000000000000000 ,

lit. Tadarida femorosacca % Photomicrograph of representative chromosome spreac oooooooooooooooooooooooooooooo

Page

U6

U6

h i

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h8

U8

h9

h9

50

51

51

52

52

v i i i

Abstract

Karyotypes of fourteen species of the order Chiroptera are

presented«, A comparative study of these karyotypes indicates that

centric fusion has played a major role in the evolution of Chiroptera

and that chromosome evolution in at le a s t two species has progressed

away from the main lin e while morphological and behavior parallelism

has been maintained.

While the data in most cases support the present c la ss if ica tio n

and phylogeny of Chiroptera, i t alsoi indicates that some revision may

be necessary.

Evolutionary trends and Interrelationships are discussed for

the three fam ilies; Vespertilionidae, Molossidae, and Fhyllostomatidae.

Introduction

Recent developments in cytologies1 techniques have caused an .

increased in terest in the study of mammalian chromosomes. Yet, the

use of these techniques as a taxonomic aid has not become widespread

among mammalian taxonomists. This can be attributed to the fact that

cytologies1 methods are not usually needed for id en tifica tion of

mammalian species and ordinarily w i l l simply substantiate the judgements

of an experienced system stist. However, the importance of these

techniques in interpreting the phylogeny of the mammalian species and

their interrelationships should not be ignored. Gain (1958) gives an

excellen t summary of the use and importance of cytology in taxonomy.

Nuclear cytology has played only a s lig h t role in the study of

the mammalian order Ghiroptera, Prior to 191*8, the information

pertaining to the chromosomes of; bats was very inconsistent. Van der

Stricht (1910) reported a haploid number of 9'. or 10 for Vesperugo

noctula, Athias ( 1912) reported an approximate haploid number of 16

for Rhinolophus hipposideris, Jordan (1912) and Hanee (1917) both

report chromosome counts of unknown species. The only re liab le infor­

mation during th is period prior to 191)8 was reported by Painter (1925), '

In h is study, he correctly determined the diploid number of NyctinomUs:

mexicanus (^Tadarida b r a s ilie n s is ),

Makino ( 191)8), using testicu lar material, determined the diploid

number of Pteropus dasymallus jnopinatus to be 38, The chromosome

complement was reported to consist of th ir ty -s ix metacentric and two

1

terminal chromosomes„ This i s the only member of the suborder Mega-

chiroptera that has been examined cy to log ies lly . The Japanese horse­

shoe bat, Rhinolophus ferrura-equinum, -Has a lso included in his study

and a haploid number of 29 >ms reported for the sp ecies.

In 19li9, Bovey studied fourteen species of Old World bats

representing three fam iliest 1, Rhinolophidae, three sp ecies | 2.

Nycteridae, one sp ecies | and 3= Vespertilionidae, nine sp ecies. His

study represents the most recent investigation of chromosomes in bats

that has come to the attention of the author,

The present investigation has three objectives s 1. to make

available to other workers cytologies1 information regarding additional

species of Chiropteraj 2. to elucidate a few problems in the taxonomy

and phylogeny of Chiropteraj and 3. to present data that w il l be useful

in future studies concerning the evolution of mammalian chromosomes. .

In Chiroptera, the phylogeny i s complex and present interpretac­

tions are often ambiguous. Cytotaxonomy can play a major role in

clarifying the relationships of many groups within th is Order. In the

present studyg four Species in the family Pbyllostomatidae, seven

species in the family V espertilionidae, and two species in the family

Molossidae have been examined by cytological techniques. The chromo­

some morphology of each i s described and illu strated in karyogram form

and selected photomicrographs are included.

Since only a few scattered species within the Order have been

studied by cytological methods, only trends in phylogeny can be shown.

The resu lts generally verify the c la s s ic a l taxonomic c la ss if ic a tio n but

in some instances show that minor revisions may be necessary. .

Materials and Methods

With the advent of the colchicine-hypotonic c itra te method of

Ford and Hamerton (1956) the study of mammalian chromosomes has been

greatly advanced. The action of colchicine is three-folds 1 . i t acts

to prevent spindle formation and thereby causes an accumulation of c e lls

in metaphase$ 2. i t causes the chromosomes to shorten; and 3 . i t causes

the s is te r chromatids to separate, showing the exact position of the

centromere. The action-of the hypotonic c itra te solution complements

the action of the colchicine by expanding the c e l l .

To date there are several good techniques u tiliz in g the

colchicine-hypotonic c itra te method. The one chosen for th is study is

described by Fatten (1965) and involves the following steps:

1, Inject liv e animals intraperitoneally with colchicine

(0.05 grams percent), 0,01 ml, per gram body weight.

2, Sacrifice the animal after seven hours and immediately

remove the complete humerus. The epiphysis i s cut o ff and the bone

marrow removed from the shaft by flushing with 3 ml. of 1.0 percent

sodium c itra te . Pipette solution vigorously to break up any c e l l clumps.

3, Incubate the resultant c e l l suspension a t 37° C for 30

minutes, . . . .

F ilter solution through two layers of cheese cloth and

centrifuge at 500 rpm for five minutes.

5. Pour off supernate without disrupting the button, add 3 ml.

of freshly prepared Carnoy8s fixa tive and allow c e lls to f ix in a c o l d ,

3

box for 30 minutes„

6. Centrifuge at $00 rpm for five minutes and then wash several

times without disrupting the button,

7, Pour off supernate and add about 0,7 ml, of fix a tiv e . Re­

suspend c e lls by pipetting vigorously.

8, Pipette droplets of c e l l suspension onto chemically clean

s lid es and ign ite the suspension immediately, following the blaze-dry

method of Scherz (1962). Allow slid es to dry,

9. Stain in aceto-orcein for one and one half hours.

10. Dehydrate in three, 30 second changes of absolute methanol

and mount.

After the s lid es were prepared each was scanned for w ell spread

metaphase p la tes. Those c e lls that appeared intact with the c e l l

membrane undamaged by the preparatory technique and with chromosomes

spread symmetrically were used to obtain the fin a l diploid number of the

species. Cells that showed chromosomes widely separated and with other

c e l ls in the v ic in ity were disregarded. Any spreads that showed

chromosomes representing different m itotic stages or reacting in d iffer ­

ent ways to the sta in were also disregarded. The c e lls selected to be

counted were then placed under 1280 X magnification and counted several

times by v isu ally dividing the chromosome complement into several groups.

Photomicrographs were taken of at lea st s ix spreads for each species

and then the chromosomal complement was again counted.

A Zeiss microscope equipped with a 3$ mm. camera was used and

photomicrographs were taken on Kodak high contrast copy film .

For karyogram an alysis, intact c e lls were chosen based on the

following criter ia s 1 . c e l ls showing the lea st amount of overlapping

of chromosomes| 2. c e lls exhibiting the highest degree of chromosome

morphological acuity; and 3. c e lls representing mitotic metaphase. In

describing the karyogram, the standardised terminology of Patton (1965)

was used. In h is description, there are four types of chromosomes

based on arm ra tio s . The median chromosome possesses a median centro­

mere and has an arm-ratio between 1 :1.0 and 1 :1, 09; the sub-median

chromosome has a submedian centromere and an arm-ratio between 1 :1,10

and 1 :1 .99; the sub-terminal chromosome has i t s centromere subterminal

and an arm-ratio 1:2 or greater; the terminal chromosome has no v is ib le

second arm. Metacentrics refers to both median and submedian chromo­

somes while acrocentrics refers to both terminal and subterminal

chromosomes.

For karyogram analysis, the chromosomes were separated into

groups according to their, morphology and comparative s iz e . In many

instances, a group contained a series of chromosome pairs that gradually

decreased in size without any obvious breaks in the ser ies; thus the

group was not further subdivided.

The sex chromosomes were determined on the basis of the hetero-

morphic pair found in the males. The non-homologons pair was designated

as the sex chromosomes and I - and T- determination was decided from the

female karyotype which consists of a homomorphic X-complement.

Live bats used in th is study were collected in Japanese "mist"

nets and hand nets. The Japanese "mist" nets were employed over water

holes and in the entrances of mine tunnels and caves. Hand nets were

employed inside mine tunnels and eaves where bats were found clinging

to the w alls»

Specimens were identified on the basis of external morphology

and skull ch aracteristics« They are a l l now located in the museum at

the University of Arizona as part of the permanent co llec tion . Local­

i t ie s and catalog numbers are lis ted in Appendix C,

The taxonomy and c la ss ifica tio n of the bats used in th is study

was based on Hall and Kelson (1959)$ Simpson (19li9) and Miller (1906).

Results

Fourteen species (including four species in the family Phyllo-

stonmtidae, eight species in the family Vespertilionidae, and two

species in the family Molossidae) have been examined for chromosome

morphology and diploid number. The numerical resu lts from th is study

are lis ted in Table 1, and the morphological description of each species

karyotype is given below. Representative karyotypes and photomicro­

graphs are presented in Appendix A and B respectively.

Species Examined in the Family Phyllostomatidae

Pteronotus davyig Subfamily Chllonycterinae

Two male individuals were examined and the species' diploid

number was determined to be !|0. A representative karyotype (Plate 1,

Appendix A) shows three groups into which the chromosomal complement

was separated based on chromosome morphology and s iz e .

Group A consists of s ix large pairs of approximately equal

sized metacentric chromosomes with either medial or submedia1 centro­

meres.

Group B consists of five pairs of medium sized to small meta­

centric chromosomes with either medial or submedia1 centromeres.

Group C consists of seven pairs of small to very small terminal

chromosomes.

Since only male specimens were studied, X and Y designation of

sex chromosomes was not possib le . Structurally, one of the sex

Table I , Summary of diploid numbers„ autosomal types3 sex chromosomes, and fundamental numbers of the species studied in the order Ghiroptera.

Family and Species 2n M SM ST T X-I NF* cT $Phyllostomatidae

Pteronotus davyi 38 u 18 lit (M T) 56 2 0

Macrotuswaterlaousii 1|0 2 18 2 16 SM T 60 3 2

Leptonyeterisn iva lis 32 lh 16 =»«=> csiaes, (SM SM) 60 0 3

Choeronycteris mexicanus 16 b it It it ?' ? (26) 0 1

FespertilionidaeMyotis

thysanodes 14; 2 6 3it SM SM 50 it 1

Myotis volans ifU 2 6 — 3it M T 50 1 1

Myotis“TorEIdens a 2 6 3U (SM T) 50 1 0Pigonyxvxvesx a 2 6 o e e=» 3it (SM T) 50 2 0

P ip istrellu s"Hesperus 28 lit 8 esaeo 6 (SM T) m 0 1

Eptesicus50 «ae«ao. 2 a (SM T) m 0 2

Lasiurus"cinereus 28 lit 6 6 SM T it6 2 1

LasionycterisnocMvigans 20 ' it 6 2 6 SM T 30 2 0

MolossidaeTadaridatr a s ilie n s is 1|8 6 itO M T (5it) 2 2

Tadarida CO 8 it 36 (SM T) (58) 0 1

* M 88 medial centromere| SM « submedia 1 centromere5 ST «= subterminal centromere| T = terminal centromere.! HF = fundamental number.

chromosomes is a small metacentric type with a submedial centromere

belonging to group B and the other a medium sized terminal chromosome

belonging to group Go

Macrotus waterhousiis Subfamily Phyllostominae

Three specimens, one male and two females were studiedj the

sp ec ies’ diploid number was determined to be !j.0o Fire morphological

groups can be e a s ily separated in the karyotype (Plate 2, Appendix A)«

Group A includes eight pairs of large to medium sized meta-

centric chromosomes. Pair it i s the only chromosome in the karyotype

with a medial centromere.

Group B includes one small pair of submedial chromosomes.

Group C includes one characteristic pair of large subterminal

chromosomes,

Group D includes five medium sized terminal chromosomes.

Group E includes three pairs of small to very small terminal

chromosomes.

The X-chromosome was determined to be a small submedian chromo­

some belonging to group B, The T-chromosome, not shown in the female

karyotype, i s a terminal chromosome.

Ghoeronycteris mexicanuss Subfamily Glossophaginae

One female specimen was examined from which the species diploid

number of 16 was determined. The karyotype (Plate 3 , Appendix A) is

e a s ily d iv is ib le into four groups.

Group A consists of two large pairs of chromosomes5 pair 1

includes two large subterminal chromosomes and pair 2 includes two

10

large submedial chromosomes.

Group B consists of two pairs of medium size chromosomes} one

• subterminal pair and one submedial pair.

Group C consists of two small pairs of medial chromosomes.

Group D consists of two pairs of terminal chromosomes} one

large pair and one smaller pair.

Since only one female was examined the sex^-chromosomes could

not be determined,

Leptonycteris n iva lis s Subfamily Glossophaginae

Three female specimens were examined and a diploid number of 32

was determined for the species. The karyotype (Plate ij.s Appendix A)

consists of a l l metacentric chromosomes and is d iv is ib le into two

groups based on s iz e .

Group A includes five pairs of large metacentric chromosomes

with either medial or submedial centromeres.

Group B includes the remaining eleven pairs of metacentric"

chromosomes which range from medium to small in s iz e .

Sex chromosomes could not be determined because only females

were examined.

Species Examined in the Family TTespertilionidae

Myotis thysanodes s

Three individuals were examined, two males and one female, A

diploid number of Wi was determined for the species. The karyogram

(Plate 5, Appendix A) shows three morphological groups that are ea s ily

discernable in the karyotype.

Group A i s composed of three large pairs of metacentric chromo­

somes with either submedia1 or medial centromeres.

Group B contains a single pair of small metacentric chromosomes

with medial centromeres.

Group C includes seventeen pairs of medium to small sised term­

in a l chromosomes.

The submedial X-chromosome i s smaller in size than the chromo­

somes of group A and larger than the chromosomes in group B. The Y-

chromoeoae is the sm allest metacentric chromosome in the karyotype and

has a medial centromere.

Myotis volansg

Two individuals of th is species were examined, one male and one

female. A diploid number of lilt was determined for the sp ecies. As

found in Myotis thysanodes, the autosomal complement could be e a s ily

divided into three morphological groups as shown in the sp ec ies , karyO-

gram (Plate 6 , Appendix A).

Group A includes three pairs of large metacentric chromosomes

with either medial or submedial centromeres.

Group B contains a single pair o f small metacentric chromosomes

with medial centromeres. • v- -

Group C includes seventeen pairs'of large to small terminal

chromosomes =

The X-chromosome is a medium sized metacentric type with a

medial centromere and i s e a s ily recognized in the karyotype because of

i t s characteristic s iz e , smaller than those of group A and larger than

12.

those of group B. In contrast, the Y-chromosome is a small terminal

chromosome of group C.

Myotis fortidens:

The karyotypes of a l l three Myotis studied are morphologically

indistinguishable from each other. The karyogram of Myotis fortidens

(Plate 7 ) Appendix A ) shows chromosomes s lig h tly larger than those of

the other two species of Myotis but th is difference is due to the use

of an earlier stage in mitotic d iv ision .

The diploid number is h h and the karyotype i s divided into

three groups.

Group; A consists of three pairs of metacentric chromosomes with

the largest, pairs 1 and 2, having submedial centromeres and the small­

e s t , pair 3, having medial centromeres, . ■

Group B i s composed of a single small pair of submedial chromo­

somes ,

Group G includes seventeen pairs of terminal chromosomes.

Since no female specimens were examined the X- and Y-chromosomes

were arb itrarily assigned based on the findings of other species. The

X-chromosome is a medium sized metacentric type with a s lig h t ly sub^» ■'

medial centromere and i s e a s ily distinguished, because of s iz e , from

the remaining chromosomes. The Y-chromosome is a small terminal type.

Pizonyx v iv es i g

Two male specimens were examined and the species diploid

number was determined to be Wi. The karyotype (id en tica l to the Myotis

karyotype) was divided into three groups, (Plate 8, Appendix A).

Group A includes three large pairs of metacentric chromosomes

with either medial or submedia1 centromeres. A ll three pairs are of

approximately the same s iz e .

Group B includes a single small pair of submedia1 chromosomes.

Group G consists of seventeen pairs of terminal chromosomes

varying from the largest (pair number 5 ) to the sm allest (pair number

21).The sex chromosomes are recognizable morphologically but could

not be designated as X or T since no females have yet been examined

cyto log ica lly . I f , however, i t i s assumed that the same pattern is

followed as was found for the genus Myotls, from which they can not be

karyologically distinguished, we can arb itrarily designate the medium

sized metacentric sex chromosome as X and the smaller morphologically

undefined chromosome as Y. '

P ip istrellu s hesperus:

One female specimen was examined from th is species and a

diploid number of 28 was determined. The species karyotype (Plate 9>

Appendix A) was divided into four morphological groups.

Group A includes two large pairs of metacentric chromosomes $

pair 1 has medial centromeres and pair 2 has submedia1 centromeres.

Group B contains eight medium sized pairs of metacentric chromo­

somes with either medial or submedia1 centromeres. There i s a s lig h t

decrease in s ize from pair 3 to pair 10.

Group G includes a single small pair of medial chromosomes.

Group D includes three pairs of terminal chromosomes that

exhibit a s lig h t decrease in s iz e .

Sex chromosomes could not be determined since only females

were examined.

Bptesicus fuscusg

Two females were examined. The species diploid nrunber was

determined to be 50. The karyotype of the species (Plate 10, Appendix

A) could only be divided into two morphological groups.

Group A consists of one large pair of medial chromosomes which

represents the only metacentric type found in the karyotype.

Group B i s composed of the remaining twenty-four pairs of

terminal chromosomes = There is a gradual decrease in size of the

chromosome pairs without showing any breaks for further subdivision of

the group.

Sex chromosomes could not be distinguished since only females

were investigated.

Laslurus cinereus s

Results obtained from two specimens, one male and one female,

show a diploid number of 28 for the species. The representative karyo­

type is illu strated (Plate 11, Appendix A) showing the three morpho­

lo g ica l groupings into which the autosomal complement i s divided.

Group A includes s ix large pairs of metacentric chromosomes

with medial or submedia1 centromeres. A ll pairs are of the same rela­

tive size with the exception of pair number 6 which i s s lig h tly smaller.

Group B includes four small pairs of metacentric chromosomes

with medial or submedial centromeres.

Group C includes three pairs of terminal chromosomes.

The 2-chromosome, as illu strated in the karyogram, i s a large

metacentric -with a submedial centromere and could be included in group

A based on size and morphology. The Y-chromosome, not shown in the

female karyogram, was determined to be a small terminal chromosome.

Lasionycteris noctivagans:

Two individuals, both males, were studied and the species

diploid number was found to be 20. The karyotype (Plate 12, Appendix A)

was divided in four autosomal groups.

Group A consists of two large pairs of submedial chromosomes

which can be distinguished from each other by the more d is ta l location

of the centromeres in pair 1 and the more medial location of the centro­

meres in pair 2,

Group B includes three pairs of medium sized metacentric chromo­

somes which can be individually identified by the location of the

centromeres. Pair 3 is subterminal| pair U i s medial and pair 3 is sub­

medial.

Group C consists of an extremely small pair of medial chromo­

somes.

Group D contains three small pairs of terminal chromosomes. -- -

Sex chromosomes of th is species are determined morphologically

but a t th is time cannot be designated x and X since no females were

examined. One is a medium sized submedial chromosome and i s ea sily

identified due to i t s unique s iz e , smaller than the chromosomes in group

B and larger than those of group G. The other sex chromosome appears

as a stained "spot* and i s assumed to be a terminal chromosome repre--

senting the sm allest member of group D.

16

Species Examined in the Family Molossidae

Tadarida b ra silien s is g

Two specimens, one male and one female, have determined the

species diploid number to be 1|8° The karyotype (Plate 13, Appendix A)

can be separated into three groups according to s iz e .

Group A consists of a single large pair of submedian chromo­

somes .

Group B includes three medium sized pairs of submedia1 chromo­

somes.

Group C includes nineteen pairs of acrocentric autosomes with

subterminal centromeres. ■

The Y-chromosome, not shown in the representative female karyo­

type, i s a medium sized subterminal acrocentric type. The X-chromo­

some as shown in the karyogram is a medium sized metacentric chromosome

with a submedia1 centromere.

Tadarida femorosacca g

The karyotype of th is species (Plate lli. Appendix A) was deter­

mined from a single female individual. The species diploid number is

1|.8„ The karyotype i s divided into four morphological groups which

e a s ily distinguishes i t from the karyotype of the related species,

Tadarida b r a s ilie n s is .

Group A is composed of a single large pair of submedial chromo­

somes.

Group B consists of four medium sized pairs of chromosomes with

both submedial and subterminal centromeres.

Group C is composed of a single pair of small subterminal

chromosomeso

Group D consists of eighteen pairs of terminal chromosomes.

Since only a female specimen was examined, the sex chromosomes

of th is species could not be determined 6

Discussion

Mechanisms of Chromosomal Evolution Affecting the Karyotype

The various mechanisms of karyotype evolution were discussed

extensively by White (19I45') and Swanson (1957)• In th is study, we were

only concerned with those relevant to the changes in chromosome numbers

and/or affecting the karyotype.

A. Fusion and Fragmentation (Robertsonian Variation). Robert­

son (1916) , in his studies on in sects , f ir s t suggested the phenomenon

of fusion. He suggested that the metacentric chromosomes may have

arisen by the apical fusion of two acrocentric chromosomes or according

to the formulas V ^ l + 1. This implies that the reverse process, frag­

mentation or f is s io n , i s a lso possible but further investigations have

shown l i t t l e supporting evidence in mammals.

Matthey (19^5, 19^9) has shown that centric fusion accounted

for a large part of the v is ib le chromosome changes between d ifferent

karyotypes of a llied species of la ce r tilia n lizard s. In h is work he

coined the term nombre fondamental (N .F.) or fundamental number for the

to ta l number of chromosomal arms in a complement,

B. Non-Robertsonian Variation. In th is group are a l l other ■

mechanisms a ffectin g the structural changes of chromosomes including

the various types of translocations, inversions, and deletion-duplica-

tion factors. In th is study, only pericentric inversions, ones which

could transform one metacentric chromosome into an acrocentric

18

19 ;

chromosome or vice-versa, would cause a noticeable a ffec t in the species

karyotypeo

G» Polyploidy and polysomy are not thought to have played a

sign ifican t role in mammalian chromosomal evolution and no evidence for

either case has been found in the evolution, of the Ghiroptera,

Interpreting Data Derived From Karyotypes

Before interpreting the accumulative data in Table 2, a b r ie f . .

discussion concerning the r e l ia b ili ty of fundamental numbers i s necessary.

The nombre fondamental can be determined in.two ways 3 (1) by counting

a l l arms in the complement including the sex chromosomes as Bovey has

done in his study; or ( 2) by counting only the chromosomal arms of the

autosomes, excluding the sex chromosomes, as Maithey la ter defined the

term.

Another d if f ic u lty in determining theN .F . is often encountered

in the study of mammalian chromosomes.’when, subterminal chromosomes are. ,

involved. In some karyotypes, the complement includes chromosomes with,

extremely small arms which are d if f ic u lt to detect by the present tech­

niques . Therefore, the establishment of l .F , becomes a very delicate

task and the value can be determined only in an approximate and often

arbitrary manner. ■ .■ .-

In the present study the fundamental.number has been determined

according to the system proposed by Mat they in which a l l autosomal

chromosome arms are counted. In cases where only female specimens were .■

examined, two was subtracted from the to ta l number in the assumption

that the Y-chromosomes were terminals. With only one exception, where.

20

a l l chromosomes of the complement were of the metacentric type, a l l

determined Y-chromosomes were terminal chromosomes.

In interpreting the ranges of diploid and fundamental numbers

in Table 2, i t was assumed that a l l Robertsonian variation (fusion)

reduces the to ta l number of chromosomes without changing the to ta l

number of arms. This is to say, i f a l l species in a family underwent

only Robertsonian variation we would expect to find a wide range in

diploid numbers but the fundamental number of each species would remain •

equal and unchanged. I f any other structural change played a role in-

the chromosomal evolution of the group,-we would expect to find either

a decrease or increase in the fundamental number. For example, i f a •-

metacentrie chromosome was formed by a pericentric inversion instead of

by the centric fusion of two rods, there would be an increase of two .

arms in the karyotype without a ltering the diploid number. This can

obviously work in the reverse manner and create one rod shaped chromo- - .

some from a former metacentrie type thereby decreasing the N.F. by two

in the karyotype. ■ In either case, the N.F, i s changed by two.

Therefore, changes in the N.F. can only be created by non*

Robertsonian variation but, on the other h a n d i t i s possible for non*

Robertspnian variation to counteract i t s e l f . ‘and not change the N.F. in

the resultant karyotype, i . e . one pericentric inversion creating a

metacentrie chromosome and one creating a terminal type.

Assuming that both -Robertsonian and non-Robertsonian variations .

have played a role in the karyotype evolution,, we can express numer- - .

ic a lly the degree to which each has been involved based on the range of

N.F. within the family and the range of the diploid numbers. I f the

21Table 2. Summary of chromosome numbers and fundamental numbers in Chiroptera - _______ _______Species ' ' 1 2n ' At Ac NF Investigator

MegachirpteraPteropodidae

Pteropus dasymallus inopinatus

MicrochiropteraKycteridae

Nycteris sp.

Eh inolophid aeRhinolophus euryale

Rhinolophus ferrum-equinum

Rhinolophus ferrum-equinum

Rhinolophus hipposideros

Phyllo s t oma tid a e Ghilonycterinae

Pteronotus davyi

PhyllostominaeMacrotus waterhousil

GlossophaginaeLeptonycteris n iva lis

Choeronycteris mexicanus

Vespertilionidae Myotis myotis

■ Myotis mystacinus

Myotis emarginatus

Myotis thysanodes

Myotis voIans

Myotis fortidens

Myotis daubentoni

PiBonyx v ivesi

P ip istre llu s p ip istre llu s

38 ? ? 72 Makino 'W

h2 ? r 79 Bovey ®U9

58 ? ? 62 Bovey 9U9

58 ? ? 62 Bovey 8U9

58 ? ? ? Makino *li8

k ? ? 60 Bovey ^ 9

38 22 Hi 56 Osborne *65

ko 20 18 60 Osborne 1165

32 30 6o Osborne 865

16 12 li (26) Osborne 865

10i ? ? 5ii Bovey sii9

iili. ? ? 52-5L Bovey 8li9

iiii ? ? 52 Bovey 8lt9

a 8 3U 5o Osborne *65

iOi 8 3li 5o Osborne ’65

kh: 8 3U 5o Osborne 165

h2 ? ?. 51 Bovey %9

hb 8 3ii 5o Osborne 865

b2 ? ? (51) Bovey 8li9

22

Table 2. Summary of chromosome numbers and fundamental numbers inChiroptera. ( continued)

Species 2n Mt Ac NF Investigator

P ip istre llu s hesperus 28 22 6 (1*8) Osborne '65

P ip istre llu s nathusii UU ? ? ? Bovey fk9

Plecotus auritus 32 ? ? 51* Bovey ”1*9

Barbastella barbastelius 32 ? ? 51* Bovey ”1*9

Eptesicus fuscus 50 2

CO CO-d* Osborne ”65

Miniopterus schreibersii h6 ? ? 52 Bovey ”li9

Laslurus cinerius 28 20 6 1*6 Osborne ”65

Lasionycteris noctivagans 20 10 8 30 Osborne ”65

MolossidaeTadarida brasilienses hB ? ? ? Painter ”25

TadarIda brasilienses 1)8 6 1*0 (51*) Osborne ”65

Tadarida femorosacca U8 12 36 (58) Osborne ”65

Note: Mt = metacentric chromosomes| i c = acrocentric chromosomes! HF * fundamental number

23

range of N.F, i s aero then Robertsonian variation has contributed 100

percent, on the other hand i f the range of N.F. i s equal to the range

of diploid numbers then each type of variation has contributed exactly

50 percent. By interpolating the proportional degree of variations in

N.F. we can obtain the approximate percentage of Robertsonian variation

(fusion and/or fragmentation) and of non-Robertsonian variation.

Evolutionary Trends and Relationships Within the Family Fespertilionidae

Looking a t the family Fespertilionidae as a whole, one can only

conclude that i t represents a very heterogeneous group. The diploid

numbers of the seventeen species studied vary from the lowest count of

20 in Lasionycteris noctivagans to the highest count of 50 in Eptesicus

fuscus, giving a diploid range of 30 for the family. By using the N.F.

as a criterion for analysis, a range of 26 i s observed. In either case,

the data indicate a very diverse group, a t le a s t karyotypically.

I f one separates the family into two parts, one part including

a l l the species except Lasionycteris noctivagans and the second part

including only L. noctivagans, one arrives a t a very d ifferent conclu­

sion. We can ju stify th is separation of L. noctivagans. F ir st, ana­

tomical and morphological studies by Winge (19I1I ) indicate that the

genus Lasionycteris is a very divergent member of the family F espertil­

ionidae and secondly, the cytologies1 evidence; presented here indicates .

that the genus occupies an isolated position a t le a s t karyotypically . ..

from the remaining genera studied.

By analysing the cyfcologieal data as previously described, the-,-v-

resu lts in Table 3 were obtained.

2k

Table I I I . Evolutionary trends In the family Vespertilionidae based on diploid and fundamental numbers.

Family Vespertilionidae 2n N.F. % R.7.

%Non-R* Vo

Group 1 20-50 (range 30)

30-51*(range 2U)

lilt. 7 55.3

Group 2 28-50 (range 22)

it 6-5U(range 8)

81.8 18.2

Notes 2n; = diploid number| N.F. = fundamental numberi R.7. = percent of Robertsonian variation; Non-R.V. = percent of non-Robertsonian variation. Group 1, includes a l l the studied vespertilionid species; Group 2, includes a l l the studied vespertilionid species except for L. noctivagans.

The cytologies1 evidence indicates that Robertsonian variation

has played the major role in the evolution of the vespertilionid bats

-with the exception of the single genus Lasionycterls. The la tter

appears to be karyotypically divergent and occupies a position isolated

from the remaining genera in the family.

Farther evidence of th is hypothesis can be shown in the genus

P ip istre llu s. Bovey8s study of P ip istre llu s p lp lstre llu s shows that

the karyotype of the species includes nine metacentrie chromosomes and

thirty-three rod shaped chromosomes for a diploid number of U2. Since

his study involved the male sex5 we can subtract one X-metacentric and

one T-acrocentric chromosome from the to ta l and have remaining eight

metacentrie and thirty-two acrocentric chromosomes for the species auto­

somal karyotype. P ip istre llu s hesperus, a New World representative of

th is genus, has an autosomal karyotype consisting of twenty-two meta­

centrie and four acrocentric chromosomes (see Table li). By the mechan­

ism of centric fusion we can convert twenty-eight acrocentric

chromosomes to fourteen metacentric chromosomes in P. p ip istre llu s and

th eoretica lly evolve P. hesperus which has a 2n number of 28, (twenty-

two metacentric and four acrocentric chromosomes)«

Table 17. Chromosome counts in the genus P ip istre llu s .

Species 2n Met. Acr.

P. p ip istre llu s lt2 8 32

P. hesperus 28 22 it.

Note ? Met. «* metacentric chromosomes Acr. ® acrocentric chromosomes

Cytological Evidence Suggests the Taxonomic Revision of Pisonyx v iv esi

Miller (1906) changed the generic name of Myotis v iv es i to i t s

present taxonomic status Pizonyx v iv e s i. This change in generic status

was based on the following facts s 1 . the size of the foot relative to

the tib ia exceeded that of any of the large-footed species of Myotis

and the extreme compression of the claws was unlike any member in the

related genus| 2. a glandular mass i s present near the middle of the

forearm and i s not found in any other c losely related sp ec ies. A ll

other characters f a l l within the Myotis range. The cytological data

presented here indicates that the change by Miller in the generic

status of Myotis v ivesi was not valid.and that Pizonyx v iv es i should be

put back with the genus Myotis as f i r s t described by Menegaux (1901).

As shown in the karyograms of the three species of Myotis, M. thysa#

nodes, M. volans and M. fortidens, and the karyogram of Pizonyx v iv es i.

these four individuals have identical karyotypes and cy to log ies lly

are inseparable. Each species has a diploid number of lUt and ident­

ic a l chromosomal complements composed of ttio median, s ix submediah,

and thirty-four terminal chromosomes a The s iz e relationships between

the four chromosome complements appear approximately equal when the

karyotypes from the same mitotic stages are compared.

Evolutionary Trends and Relationships Within the Family Molossidae

Only two species of the genus Talarida were studied, both shew

in a diploid number of 1|8. However, both karyotypes show morph­

ological differences which can e a s ily be used for species id e n t if i­

cation. Tadarida b ra silien s is shotjs a unique karyotype consisting

of eight submedia1, th irty -e igh t subterminal and no terminal chromo­

somes. The subterminal chromosomes a l l have extremely small second

arms which makes the concept of N.F. d if f ic u lt to apply. I f a l l of

the arms were to be co u n ted s the resultant N.F, would equal 92 as com­

pared to the N.F. of T. femorosacca, (58). By not counting the sub­

terminal arms, an N.F. of 5h i s obtained and is more c lo se ly related

to that found in T. femorosaeca which has only four subterminal chrome

somes. This striking difference may simply be due to the technique

used in preparing the chromosome material or might be explained by

a series of pericentric inversions. In either case further study on

the cytology of the molossids i s needed for a better understanding of

the mechanisms involved in their evolution.

2'7

Evolutionary Trends and Relationships Within the Family Phyllostomatidae

Within the family Phyllostomatidae, Ghoeronycteris mexicanus

exhibits a unique karyotype with a diploid number of 16. This repre­

sents the lowest diploid number that has thus far been determined in

the order Ghiroptera* Leptonycteris n iv a lis , the only other species

studied belonging to the same subfamily, Glossopbaginae, has a diploid

number of 32 and the entire complement.i s composed of metacentric

chromosomes. The karyotype of Choerohycteris mexjcanus i s composed of

s ix pairs of metacentric, two pairs of subterminal, and two pairs of <

terminal chromosomes. Pteronotus davyi and Macrotus waterhousii, the

two remaining phyllostomatids studied, each representing separate sub­

fam ilies, show diploid numbers of 38 and it© respectively . From th is

data, we can only assume that Ghoeronycteris mexicanus represents a

karyotypically divergent form in the family Phyllostomatidae while

maintaining similar morphological characteristics. The other cyto­

lo g ie s ! explanation is that th is species represents a d ifferent

evolutionary lineage and shows extreme morphological convergence in

adaptation and behavior mechanisms.

By assuming that Ghoeronycteris mexicanus i s a divergent form

and represents an isolated position in the evolution of the phyllosto- •

matida, we can speculate as to the mecbanidm involved in the evolution

of the remaining phyllostomatids by examining the karyotypes of the

other three species studied. This w il l give us the resu lt in Table 5 :

28

•which indicates that Robertsonian variation has played the major role

in the evolution of the phyllostomatids and that Choeronycteris

mexieanus probably represents an isolated position within their evolu­

tion .

On the other hand, i f we do not accept the theory that Cfaoero-

nycteris mexieanus represents a divergent form then the resu lts are

reversed and non-Robertsonian variation has played the major evolution­

ary ro le .

Table 7. Evolutionary trends in the family Phyllostomatidae based on diploid and fundamental numbers.

FamilyPhyllostomatidae 2n N.F. % R . V .

%Ron~R„¥.

Group 1 16-80 (range 28)

26-60 (range 38)

29.3 70.7

Group 2 32-80 (range 8 )

56-60 (range 8 )

75=0 25=0

Note g Group 1-, includes a l l the studied phyllostomatid species3 Group 2, excludes Choeronycteris mexieanus.

Summary and Conclusions

Improved cytological techniques have been used in a study of

fourteen species of the order Chiroptera representing the fam ilies s

Phyllostoraatidae3 Vespertilionidae$ and Molossidae, Diploid numbers,

fundamental numbers, and chromosome morphology have been determined for

each species and corresponding karyograms have been illu stra ted .

The resu lts from th is study haw provided the basis for the

following conclusionss

1. Cytological information has in most cases agreed with and

further substantiated previous work in the taxomony and pbylogeny of

Chiroptera.

2. Karyotype differences can be seen in a l l species examined

with the exception of two genera, Myotls and Pissonyx.

3» The three species of Myotis g M»- thysanodes, M. volans, and

M, fortidens have sim ilar karyotypes and. can not be distinguished from

each other«

It. Cytological evidence suggests that Pizonyx v lv esi should

be Myotls v iv s s i .

5. Centric fusion has played the major role in the evolution

of Chiroptera.

6. Centric fusion can be demonstrated theoretica lly as the

mechanism for the evolution of the New World P ip istre llu s hesperus from

the Old World P ip istre llu s p ip is tr e llu s . - . .

29

7. Lasionycteris noctivagans represents a divergent genus

occupying an Isolated position in the phylogeny of the family Vesper-

t ilio n id a e .

8. Ghoeronycteris mexicanus shows extreme karyotypic diver­

gence in the family Phyllostomatidae,

Appendix A

8X »*1 o

%n•an

6XXXNo

* V7w y

i i

0 9

» V12

W V13

V 4#a# a#

16

# w

17+ ¥

18

10

« # #

15

1. Representative male karyotype of Pteronotus davyi(2l4,OOOX)

X X K A Kx HX5 6 7 8

K*B WK

10 X X

c KAD ou \,\> uu oo

0016E V v V V - ~17 18 19

Plate 2. Representative female karyotype of Macrotus waterhousii( 2k, 000X)

(Hii n :

Plate 3. Representative female karyotype of Choeronycteris tnexicanus (2li,OOOX)

a m

1 2 1

0d

n u6 7

H *8 Q

U K 810 11

K X12

s

% k13IK X * $ 1

114 15 16

. Representative female karyotype of Leptonycterisn iva lis (2k,000%)

35

t? n n iKK

u

M V <IU v t > V V5 6 7 8

i r U # V H U u u9 10 11 12

U U V v 0 V V V13 Ih 15 16

V V17

w V18

V w19

V *20

% ^21

MY

Plate 5. Representative male karyotype of Myotis thysanodes(24,000%)

1 2 3

B * M X14 x

c u V xr ty UVO t/ v wu ow

9 10 11 12

IS V bh# V V W V13 111 15 16

^ V w ^ # * w17 18 19

** m* + m M20 21

Plate 6. Representative male karyotype of Myotis volans(2 k ,0 0 0 X )

- m a n

Bh

= y u6

U

7Ut f

8

VO a v 0 09

0 010

Wn

U 012

V V13

Vv17

111

y u18

IS

V v19

16

* *

20

Plate 7. Representative male karyotype of I Iyotis fortidens(2l| ,000X)

A U 8 82

8 8Q

B / X1.

0 < c V 0 V Vn

x z oQ

U V

o

U i # w

0

<1 0

9

U V

10

V v1 )l

11

u u12

V w

V V17

-L4

u v18

-LJ>

19 20

« »21

Plate 8. Representative male karyotype of Pizonyx v ivesi(2U,000X)

39

- # # X tfb X8 XX

3 5 6

MX *& XM7 8 9 10

C * X11

D U u w» v v y12 13 lit

Plate 9. Representative female karyotype of P ip istre llu shesperus (2^,000X)

A * 81

b V U 9U V U U U2 3 b 500 00 00 «o6 7 8 9

uo u» w w w u10 11 12 13WOWO uu uv

114 15 16 17w » v y w u v18 19 20 21

U U w ¥ 0 0 * *

22 23 214 25

Plate 10. Representative female karyotype of Eptesicus fuscus(2ti,000X)

m i ix ii1 2 3 kn x*

5 6

x x xx xxIXX X

V V8

# *11 12

9

W V13

10

Plate 11. Representative female karyotype of La slum s cinereus(2i;,000X)

8 1

3

v #

# #7

¥ ¥8

12. Representative male karyotype of Lasionycterisnoctivagans (2l^,000X)

( (

u2

8 13

n14

9 95

n

6 7

#8 Q

# if10

v •11

M

7

1 o« « M

« »16

13

V V17

14

18

13

V V19

# V20

» V21

V v

22

V W

23

13. Representative female karyotype of Tadaridab rasilien sis (2U,000X)

Uh

nb yy sev*j»#vC V «r

D o v V u VO VI I10

t) V v u v v v v11 12 13 Ikv v v v «#« v v

15 16 17 18vVW«#«* «# •19 20 21 22

W #23 2k

Plate lli. Representative female karyotype of Tadarida femorosacca(2li ,000X)

Appendix B

Figure 1. Pteronotus davyi: Photomicrograph of represen­tative chromosome spread (9,600X)

Figure 2. Macrotus waterhousii: Photomicrograph of repre­sentative chromosome spread (9>600X)

Figure 3• Choeronycteris mexicanus: Photomicrograph ofrep resen ta tive chromosome spread (9,600X)

Figure k» Leptonycteris n iv a l is : Photomicrograph of repre­sen ta tive chromosome spread (9,600X)

Figure 5>. Myotis thysanodes: Photomicrograph of repre­sen ta tive chromosome spread (9,600X)

Figure 6 . Myotis volans: Photomicrograph of representative chromosome spread (9>600X)

& 5

f t

##

Figure 7. Myotis fo r tid e n s : Photomicrograph of represen­ta t iv e chromosome spread (9>600X)

Figure 8. Pizonyx v iv e s i : Photomicrograph of rep resen ta tivechromosome spread (9>600X)

Figure 9. P ip is tre llu s hesperus: Photomicrograph of rep re­sen ta tive chromosome spread (9>600X)

50

Figure 10. Eptesicus fuscus: Photomicrograph of represen­ta tive chromosome spread (9,600X)

* * #

Figure 11. Lasiurus cinereus: Photomicrograph of repre­sentative chromosome spread (9,600X)

■8)PFigure 12. Lasionycteris noctivagans: Photomicrograph of

rep resen ta tive chromosome spread (9>600X)

52

Figure 13. Tadarida b r a s ilie n s is : Photomicrograph of repre­sentative chromosome spread (9>600X)

Figure lit. Tadarida femorosacca: Photomicrograph of represen ta tiv e chromosome spread (9>600X)

Appendix G

Pterono-bus davyis Two specimens examined | (2^1), Gueve de la

Tigre, Sonora, Mexicoj UA 13^20, Minos Arm olillo, Sonora, Mexico.

Macrotus w terh o u siii Three specimens examined $ UA 13hl2 ,

UA UA 13h l6p Gueve de la Tigre, Sonora, Mexico.

Ghoeronycteris mexicanusg One specimen examined| UA 11530,

Madera Canyon, Pima Co., Arizona.

Leptonycteria n iva lis g Three specimens examinedj UA 13U21,

Minos Armolillo, Sonora, Mexico; (57), (58), Colossal Gave, Pima Co.,

Arizona.

Myotis thyaanodess Three specimens examined; UA 11536, UA 11537

(225), Madera Canyon, Pima Co., Arizona.

Myotis volans: Two specimens examined; UA 11519, UA 11522,

Santa Catalina M ts., Pima Co., Arizona.

Myotis fortid en s: One specimen examined; UA 11538, Colima,

Mexico.

Pizonyx v iv e s i; Two specimens examined§• UA 13l|25, UA 13h26,

San Carlos %y, Sonora, Mexico.

P ip istre llu s hesperus t One specimen examined; UA 13U22, Minos

Armolillo, Sonora, Mexico.

Eptesicus fuscuss Two specimens examined; UA 13h2k, Pima Co.,

Arizona; ( l 6h), Tucson, Pima Co., Arizona.

Laslurus cinereuss Two specimens examined; UA 11517, UA 11520,

Santa Catalina M ts., Pima Co., Arizona.

Lagionycteris noctivaganss Two specimens examined| UA 11518,

UA 13b233 Santa Catalina Mts, 3 Pima Co., Arizona«

Tadarlda b r a s ilie n s is ; Two specimens examined j UA 13ltl8, (252),

Cueve de la Tigre, Sonora, Mexico,

Tadarida femorosacca % One specimen examined| UA 13519, Minos

Armolillo, Sonora, Mexico.

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