Guide toL1VING AMPHIBIANS

Previously published titles in this series

Guide to Invertebrate Animals (Second Edition)Guide to Living ReptilesGuide to Living BirdsGuide to Living Mammals (Second Edition)

Guide to Living Fishes

Guide toLIVING AMPHIBIANS

J. E. WEBBProfessor ofZoology, WestfieId College,

University ofLondon

J. A. WALLWORKReader in Zoology, WestfieId College,

University ofLondon

J. H. ELGOODFormerly Associate Professor ofZoology,

University of Ibadan, Nigeria

© J. E. Webb, J. A. Wallwork and J. H. Eigood 1981

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Preface

The Guide to Living Amphibians completes this series

of six volumes which also includes guides to the invertebrates

and the living fishes, reptiles, birds and mammals, and thus

covers the entire animal kingdom. In common with the

others, this volume uses an annotated classification to

give a basic understanding of the structures and relationships

within the group, a concept that has been successfully

developed over many years in the training of students .

Among the vertebrates alive today the class Amphibia

is one of the smallest and least well known. Amphibians

were the first tetrapods and even the modern forms retain

strong similarities in structure, physiology, behaviour and

life history with their fish forebears . Somethine of this

i s shown in the chapter on tetrapods which links this guide

with the Guide to Living Fishes.

Modern amphibians are very different from their

ancestors that first climbed onto land in the Devonian

Per iod and became the dominant land animals in the

Carboniferous. Salamanders, caecilians, frogs and toads,

are mostly relatively small with the ancestral dermal armour

lost and the internal skeleton modified and much reduced .

They are recognised as amphibian mainly from their life

cycles, for most are tied to water for breeding, laying

jelly-encapsulated eggs in water or damp places and having

aquatic larvae. Although none of the extant groups is well

represented in the fossil record, all evidently arose early

in the Mesozoic when the break up of the single supercontinent,

Pangaea, was beginning. As a result, in spite of their

limited powers of dispersal and the fact that salt water

v

is a ma jor barrier, a mphib i a ns a re fo u nd o n a l l t he tropical

and t emp erate land ma s ses. Neverthele ss some f amilies are

in d ecline a nd others a ppe a r to be a da pt i vely r ad i ating ,

so tha t there are i nterest i ng pa t t erns of dis t ribution which

a r e s hown in the maps t ha t a c compa ny the f amil i es.

There are f ew up- t o -date textbooks on t he Amphibi a.

Some of t hese and some useful r ece n t papers giving a n e ntry

into the l i t era t u r e a re ment i oned in the i ntroduc tion a nd

on page 16 . The guide has no i ndex a s t h is function i s

s erved b y t he lis t of c on t ent s , whi ch sets out t he

c l assi f ication u s ed , t he glossary , b y the l i s t s of generic

a nd commo n name s a nd b y t he cros s -refer e nci ng o f t e x t a nd

fi gur e s t h r ough pa ge numbers in bra ckets.

We again thank Mrs Margaret Clarke for t he preparation

o f t he typesc r i pt f or lithography and Ph il Br ook s for t he

d r awing s o f t he a nimal s . We a re part i c u larly indebted t o

Dr Ri chard C. Tinsley for much he l p a n d di s cus s i on a bout

t he classification of t he Amphibi a and f or a dvice on t he

many problems t his has raised . However, t he inter pretat ions

a nd t he r e spon s ib i l i t y fo r errors a re ours .

JEW

~W

JHE

London, March 1980

vi

Contents

Pa ge

INTRODUCTION

Cla s si f ica tion of t he Amphib i a . •.. •. • •. . •• .•. • . •.. 2

Use of t he Guide . • . . • ••••• • • ..•. •.. • • •• ••••. •. • •. • 3

2 THE TETRAPODS •• • • • • • ••• • • • • • • • •• • •. • • . .. •.• • •• •••• •. . . • • 5

Superelas s Te trapoda • •• • •• •• . . . • . • • • • • • • • . • .••• •• . 7

3 AMPHIBIANS . • • • . • . . . . . . . . • . • • . • • • • . • . . • . • • • • • • • • • • . • . • • . . 13

Class Amphibia .• . . . . • •• • •• . .• .• .• . •• . • • • •• • • .• . . .• 17

4 NEWTS AND SALAMA NDERS • . •• . • • • • ••• •• . • . • • • • . • . •• . ••• •• • . • 29

Order Urodela .. •. • •.•• ••• •.• •. • • • . • •••.•• •.• . •.• • . 3 1

Su per fa mi l y Cryptobranchoidea .• • . • • . . • . • . . .• . . 35

Family Cryptobranchidae • . . . • . • . . •• • • .• . • . . .• 36

Family Hynobiida e • • . • • . .. .• . . . . . . . . .. . . . . . .. 40

S uperfa mi l y Salamandroidea •••.•• •• •.. . • .. ... . . 42

Family Salamandrida e ..... .... .. • . • . .. . . .. . .. 44

Family Amphiumidae • • . . . . • . . . . . . . .• .• . . . • . . . . 46

Family Proteida e ..• .• •. •.. •. .. •..•.. ... . . ... 48

Family Ambystomatida e • . . • • . . . • .• . • • . . . . . . . .. 50

Family Plethodontidae . .••• • . . . . • . • .• .• .• . . . . 5 3

Superfamily Sirenoide a •••• .•. • •. • .•. •. . •... • •. 56

Family Sirenidae • •• • .. • . • . • . • . •• . •. • . • • . . . . • 57

5 CAECILIANS

Order Apoda . . • •.• • •• • • • • • •• • • . • . • .• • . • • • • • • . .• ••••

Family Typhlonectidae .••.••.•••.• ••• ••••..••

Family Caeciliidae • •• • • • • • • ••• • •• • •• •• ••• •• •

Family Ichthyophiida e • • • ••••.•.• • ••••.•.••• •

Family Scolecomorphidae •.••.••• •••.•.•.••• ••

vii

5961

66

68

6971

C 0 N T E N T S

6 FROGS AND TOADS

Order Anura • • •• • •••••• •• • • • • ••• •• • •• • • ••• • •• • • • ••

Suborder Archaeobatrachia •••.•• ••.•.•••.• ••••••

Family Leiopelmatidae ••• • • • . . • • • • . • • • • • • . • •

Family Discoglossidae . ••.• •.•.•• •.• • •••••••

Suborder Aglossa . • •••. ••••. •••• •.•••••••••••• ••

Family Pipidae • •• • • . •• •. • •• . • . • . •• • . • • •• •.•

Suborder Rhinophrynoidei ••.••.••• • .•.••• • •••. ••

Family Rh inophrynidae • •.• . •• . •.• . . • . • •. • •••

Suborder Pelobatoidei . • ••.. •. • • • ... •. . •••. ••.. •

Family Pelobatidae • . • • • •• • • • . •••• •• • •• •• • .•

Page

72

77

84

93

96

98

99102

103

105

106

7 THE NEW FROGS • .• ••• • • • •• •• • . .••• • • • • ••• • . • • • • •• • • • • • •• • 109

Suborder Neobatrachia •• ••• • • •• • . . • .• . . .• • • • .• •• 111

Superfamily Bufonoidea • ••••••• •••• •• ••• ••• • •• 112

Family Bufonidae • • • • • •• • • • • • • •• • • •• • •• • • . • • 116

Family Leptodactylidae •• ••••• •• • •••• • •• • . •• 120

Family Hylidae • • • • • • .• • • • • • • • •• • • • • • •• • • •• • 124

Superfamily Ranoidea • • • •• .• •• •• • • • •••• • • . • • • • 127

Family Ranidae ••• •••••••• •••••• •••••• .••• •• 129

Family Soogl o s s i da e • • ••••.•.•... •...•.••••. 131

Family Rhacophoridae •• •••• •••••• • •••• •••••• 133

Superfamily Microhyloidea • • •••• •••.•••••••••• 135

Family Microhylidae ••• • •••.•.•• •. •••• ••••• • 136

8 GLOSSARY. • • • • • • • • • • • • • • • • • • • • • • . • • • • • • • . • • • • • • • • • • • • • •• 13 8

List of g e ner i c name s quoted • • • • •• . .• • • . •• • •• . . • • 142

List of common names quoted •• •.• •• •..•• • •••••. ••• 144

viii

1 I ntroduction

Living amphibians and r eptiles are comparatively

small groups of vertebrates which it has become COmmon

practice to treat together as the study of herpetology,

particularly for t eaching purposes. The reptiles a r o s e

from the amphibians in the Upper Carboniferous Per iod and

at that time the two groups were structurally so similar

that it is difficult to distinguish between them . However,

this similarity does not extend to their living

representatives . The amphibian body has undergone much

structural reduction . All living amphibians are highly

specialised and have diverged considerably from the

primitive form . The same applies to many of the living

reptiles, notably the snakes, although some r e pt i l e s , the

turtles, crocodiles and the tuatara, have retained an

essentially primitive structure. Adaptive radiation in

the modern reptiles is chiefly structural a nd behavioural,

whereas in modern amphibians, particularly the anurans, it

is mainly reproductive and involves various ways of

circumventing the problem of returning to water to breed.

The two groups, therefore, exemplify different aspects of

zoology . It is for this reason that the living amphibians

and the living reptiles have each been treated in a

separate guide in this series.

The guides to the living members of the tetrapod

classes, amphibians, reptiles, birds and mammals,differ

from the guides to invertebrates and living fishes in an

important respect. In general the tetrapods or land­

living vertebrates are more completely known in terms of

extant species than any other group of animals. It

I N T ROD U C T ION

therefore seemed desirable that the tetrapod guides should

be comprehensive and include all the families into which

the four classes are divided. This is not to say that

all familial names proposed by different authorities have

been quoted,because the approach to classification used here

has been conservative. Many families distinguished here

have been subdivided into two or more families by different

people at various times, but such splitting is difficult

to support in terms of sets of matching ctaracters, often

because the information is not available. The invertebrates

and the fishes are too extensive and too complicated to be

treated in this way within the scope of the present series

of guides. Such groups as the insects and the teleost

Acanthopterygii, for example, would require separate

volumes.

Classification of the Amphibia

The state cf the classification of the Amphibia is

less weIl advanced than that of the higher tetrapods.

Considerable research in the last twenty years has done

much to clarify the relations between the differer.t

amphibian families, particularly in the ffiOSt difficult

group, the Anura. New characters and old have been

investigated and the weight that should be given to each

has been computed through numerical taxonomy by A.G. Kluge

and J.S. farris (1969) in Syste~atic Zoolo~X' 18, 1-32.

A fully satisfactory system is elusive, however, and there

is much controversy among authorities even about the levels

of the higher taxa. To some extent this applies to the

reptiles, birds and mammals as weIl, but to an altogether

lower degree. The classification of these classes, due,

probably, as much to the greater number of systematists

in these fields as to any inherent difficulties in the

classes, has reached astability that amphibian systematics

has yet to attain.

In constructing this guide to the living amphibians

it has been impossible to follow completely any established

pattern of classification, though parts of many have been

incorporated . It has been necessary to corrpile sets of

2

I N T ROD U C T ION

matching characters and assess their value in the light

of knowledge that the resulting classification is not

quite like any that has been previously proposed. For

this no apology is made. The aim has been to achieve a

functional arrangement not greatly at variance with current

phylogenetic opinion. The classification of the Apoda

is simple, but perhaps this is an illusion and due to

paucity of information on these burrowing tropical forest

animals which are difficult to find. The classification

of the Urodela is also relatively straightforward, a!though

this interpretation differs considerably from that of

K.R. Porter (1972) Herpetol~, W.N. Saunders Company,

Philadelphia, London, Toront~but less so from that of

C.J . Goin, O.B. Goin and G.R. Zug (1978) Introduction to

Herpetology, 3rd edition, W.H. Freeman & Company, San

Francisco. The Anura are a problem of greater magnitude,

as can be seen from I. Griffiths (1963) 'The phylogeny of

the Salientia' , Biological Reviews, ~, 241-292, Kluge

and Farris (loc. cit.), J.L. Via! (1973) Evolution~

biology of the anurans, University of Missouri Press and

W.E. Duellman (1975) 'On the classification of frogs',

Occasional Papers of the Museum of Natural Historl'

University of Kansas, ~,1-14. The classification of

the Anura used here is in general, but not precise,

agreement with those proposed or implied in these works,

which also provide bibliographies on the Amphibia. The

best general texts on the Amphibia are G.K . Noble (1954)

The biology of the Amphibi~, Dover Publications Inc.,

New York, (although the classification is out of date),

and the works by Porter and Goin et al. (loE' ci!.).

Use o! the Guide

As in the other guides in this series, a system of

matching characters has been used throughout. The list

of characters diagnostic of the amphibians on pages 17 & 18

deals with the same structures in the same order as those

for the other vertebrate classes, see, for example, pages

25-26 of the Guide to Living Reptiles. Within the

3

I N T ROD U C T I O N

Amphibia, matching characters for e ach order, Ur odel a ,

Apoda and Anura, are arranged so that the differences and

resemblances between the orders become immedia t ely apparent,

and similarly for the suborders within an order and so

forth. In these s e t s of matching characters, s ome wi l l

be of g r e ate r import ance for dia gnosis than o thers. These

have been marked with a black s pot. Many of t he

c ha ra cte rs a r e illustra t ed a nd r e f erence t o t he figures

is g ive n b y t he pa ge numb ers in b r acke ts af t er t he c ha r acte rs .

Cross-reference i s al s o give n i n the g l o s s a ry a nd in

the l i sts of examples quot ed b y scienti f i c a nd c ommon

names. The relationships betwe en t he g r ou p s a re s h own

schematically and there a r e sketches of t ypi cal members

and distribution maps of the families. Th is guide will

be found helpful in a number of ways a few of whi ch a r e

listed b elow.

• I t provides a conspe c t u s of t he recent a mphibians

from which t h e r ange of divers i t y c a n be a p pre c i ated.

• Schema ti c dia grams s how t he ba s ic c l a ssificat ion in

t erms o f the r ela t i onships t hought t o e xist be tween

t he gr ou p s .

• The r e asons for t he classifica t i on are e v i dent from

the lists of matching characters. Here ne ga tive as

weIl as positive characters are g i ve n and i r releva nt

f e a tures omit t ed.

4

2 The Tetrapods

The vertebrate transition fr om life in wate r to life

on l and involved two major initial requirements, fir st

the breathing of air and secondly a means of locomotion

over the rough land surface where friction is high. In

a sense t he pr imitive fishes were preadapted for breath ing

air s ince they a l r ea dy had lungs and som e g r ou ps , j udgi ng

from their modern counterparts, the lungfishes, would have

used their lungs for air breathing. Locomotion on land

is another problem for which the t ypical, unmodified,

paired fins of the fish are not s u i t a b l e . The body of

the fish in water i s virtually weightle s s, but on l and in

the less dense medium of a i r this is not s o a nd the body

requires to be supported. To a chieve this the pa ired

fins became modified into l egs with hands a nd feet each

with f ive digit s . The legs are four movable props with

the centre of gravity of the body between them, henc e the

name tetrapod. Thi s i s not the only method of a c h i e v i ng

locomotion on land a s the l e gless lizards and s na kes s how,

but it is highly e f f e cti ve a nd ha s a lso be en u sed

extensively by the arthropods .

The pentadactyl t etrapod limb evolved in the Dev oni an

Period from the fl eshy , l eaf-shaped fin or archipterygium

of the rhipidistian fishe s. This type of fin is best s ee n

t oda y in t he Australian lungf ish, Neoceratodus, one o f the

nearest l iving r elative s o f the Rhip idist ia . It i s

characterised by a long, j ointed, c entral a x i s of bones

articulating with the limb girdle and having s y mmet r i ca l l y

arranged side bones. The colonis ation of the terrestrial

habitat wa s e v i de n t l y a grad ua l proc e s s. The first

5

T H E T E T RAP 0 D S

tetrapods, the Devonian amphibians, apart from air­

breathing and legs, were still almost completely fish-like

and probably spent most of their life in fresh water.

Here they evidently had significant advantages over many

of the contemporary fishes in that they could come out on

land when necessary and waddie from pond to pond. The

process of emancipation from water is enacted today in

the life histories of many of the modern amphibians which

begin virtually as a fish (the tadpole), breathing with

gills, and end as four-footed, air-breathing land animals.

A concomitant of life on land is the loss of water

through evaporation. Thi5 problem was not solved

immediately and has still not been solved by most Amphibia.

It was left to the reptiles to achieve an acceptable

measure of waterproofing of the skin (still not complete

in some) and to provide through the shelled egg and the

embryonie membranes a means of protecting the embryo

from mechanical damage and desiccation. Once the

tetrapods were divorced from the necessity of returning

to fresh water to breed the way was open for the

colonisation of the dry lands, the evolution of the

mammals, the conquest of the air by the birds and the

bats, and also the reinvasion of the sea by the

ichthyosaurs, whales and others.

The characters of the Tetrapoda are given here for

comparison with those of the Pisces in the Guide to

Living Fishes.

fin of Neoceratodus showing skeletal structure

6

T H E T E T RAP 0 D S

Superclass Tetrapoda

Gnathostomata in which:-

• I. The body is typically without scales (Amphibia),

covered with epidermal scales (Reptilia), feathers

(Aves) or hair (Mammalia). (19)

• 2. The paired appendages are pentadactyl limbs. (8, 81)

• 3. The head is typically carried on a neck, and capable

of independent movement, except in the Amphibia. (20)

• 4. Internal nostrils are present opening into the buccal

cavity. (20)

• 5. The snout region of the skull is weIl developed, and

the posterior skull table is reduced in size. (11)

.6. A lachrymal duct, associated with the eye socket, is

present in terrestrial forms but has been lost in

aquatic tetrapods. (li)

.7. Respiration takes place mainly through lungs. (12, 25)

8. The blood vascular system shows varying degrees of

development of a double circulation, which separates

pulmonary and systemic blood. (2~)

9. Typically the visceral arches are reduced to a 'hyoid'

bone. Internal gills may be present in primitive

tetrapods but not in higher forms. (26)

10. Typically, there is a movable tongue in the floor of

the mout.h , (20)

• 11. An allantoic bladder is present in the adults of

amphibians and in the embryos of reptiles, birds and

marnma Ls , (118)

• 12. The members are essentially terrestrial, although some

groups are secondarily aquatic .

SUPERCLASS

~----- AMPHIBIA

1------ REPTILIA

TETRAPODA-------1t------ A VES

....----- MAMMALIA

7

T H E T E T RAP 0 D S

supracleithrum

scapulocoracoid

cleithrum -----''t-

(ulna)

skeleton of a crossopterygian pectoral girdle and fin

supracleithrum

interclavicle

scapulocoracoid

skeleton of an early tetrapoß~ectora!-girdleand limb

8

T H E T E T RAP 0 D 5

a cro s s opt erygian fi n

po ssible t r a nsitional sta ge

t e trapod limb

p o s s ibl e e vol u t i on o f t e tra po d limb

9

T H E T E T RAP 0 D S

girdle pectoral fin

g irdle -----/-...

tetrapod

diagrammatic transverse sections througha fish and a tetrapod

10

T H E T E T RAP 0 D S

snout r e g ion posterior skull table

l achrymal

l achryma l wi thduc t f rom o r bitto na s al c ha mber

e xter na lna r-is -i-==-_:":':_---C

max illa

j uga l

otic notch---l--~~~~-----for tympanum

~ squamosal

quadra te

maxilla

Pa laeogyr i nu s

j uga l quadratojugal

d i a grams of the s k ul ls of a rhi idistian fish (Osteole is)a nd a Carboni erous a m hibian Pa aeo rinus showing the

i erences e t we e n a cros sopteryg1an an a t etrapo

11

T H E T E T RAP 0 0 5

gill pouches1 - 6

lungs __+- ~

gut --t------j

longitudinal section through an amphibian larva showingthe ill ouches 0 enin from the har nx and the airof lun s 7th ill ouch develo in as an out- ouchinof the gut

gut

lung

gu tI

~ ~

~::? --lung

diagrammatic longitudinal and transverse sectionsshowing the development of the lungs in a tetrapod

12

3 Amphibians

The Amphibia were the dominant land vertebrates in

the Carboniferous and were certainly the stock from which

the reptiles and in turn the mammals and birds evolved.

Like all new groups entering a virtually untenanted

environment they underwent adaptive radiation and occupied

different habitats within the limits imposed by their

general structure and physiology. The body in most was

rather crocodile-like with bony scales along the belly

and in some cases on other parts as well. The skull was

large and heavy, being completely roofed by bone. The

limbs were short and the girdles massive for the attachment

of leg muscles and the support of the body weight. The

tail was long. So me were very large up to 3 m or more

with others no more than about 10 cm in length. They

were abundant and in great variety in tropical swamps and

coal forests and uniformly carnivorous as far as we know,

as indeed are the modern amphibians. Some became mainly

terrestrial while others returned to water and were purely

aquatic with an eel-like body and limbs reduced. Amphibians

are the only tetrapods with a larva which metamorphoses to

the adult and there is little doubt that the earl iest

amphibians, in spite of the great size of some, also began

life as a tadpole.

Two major groups of extinct amphibians, the

Labyrinthodontia and the Lepospondyli, are recognised

from the structure of their vertebrae. In the

labyrinthodonts the centra of the vertebrae are ossified

from blocks or arches of cartilage, which is also the

method of formation in the frogs (Anura). The

13

A M PHI B I A N S

lepospondyls, on the other h and, have their e entra formed

direetly from the depo s i tion of bone a r ou nd t he notoehord

whieh i s often persist ent. In this ease, t he re f ore , the

ee ntra a re not preformed in eartilage . Th i s i s the

eondition also in t he newts a nd sa lama nder s (Urode la) a nd

the eaeeilians (Apoda ).

No ne of the labyrinthodonts la s ted beyond t he Triassie,

while t he lepospondyls beeame e x t i ne t e a r l y i n t he Permi an,

but a mph i b i a n lines evidently eontinued a nd a re r epresent ed

today by the three distinetly different groups of modern

Amphibia, the Urodela, Apoda and Anura. Th e urodele s a re

superfieially most like t he a neestra l amph ibians, t he

apodan s have lost their l e g s and the anurans have l ost

their tails. All are s ome t h i ng of an enigma s o f ar as

their origins are eoneerned, for their adults have r e t ained

many larval eharaeters a nd a re quite unlike t he

labyrinthodonts and lepo spondyls. Their f os s il histor y

in t h e Mesozoie, a fte r the ear ly amph i b i a ns had dis appe ared,

i s fragmentary or unknown.

I t is a general featu re of a mphib ians t hat t hey do

no t s u rvi ve in salt wa t er, salt i ntoler a nee prob ably being

r elat ed t o their inabilit y t o eone entra t e urine . As a

r e sult, amphibians have d i ff ieult y in erossing seas and

a ppea r t o have been un able to s pread f rom one l and mass

to a nother whe r e t hese were widely s epa r a t ed. Transport

on rafts of floating vegetation o ve r short d i s t ane e s i s

a l ways possible and ha s e v i dent l y l ed, for example , to

r anoid frogs erossing Wallaee' s Line betwe en Borne o a nd

Celebe s in eomparati vely r eeent t i mes . The modern

amphibians probably da t e from a time when Panga e a wa s

undivided or in the e arly s t a ge s of fragmenta tion ( s e e

Guide to Living Reptiles). The present di s tributions

of the three groups a re e v i de nt l y a re f l eet i on o f t he

positions of the eontinents in the Mesozoie and t he i r

subsequent ehanges t h r ough dr ift ing. It i s a s sum ed,

therefore, that the apodans, whieh a r e forest-livin g

pantropieal forms, probably preda te eontinental s epara tion.

14

A M PHI B I ANS

C0.-l>

o.-l

'"'"'-eC<0

-I>oC

0.-l-I>><Q)

I/)

C<0

o.-l.D0.-l..ce<0

"1'1 "~"~SOÄ4~401

I/);:l0

I/) I.::s Q)

0 0 0 ""'Q) o.-l 0.-l C o.-l

0 I/) I/) <0 C<0 I/) I/) 0.-l 0-I> <0 <0 e .DQ) I. 0.-l I. I.I. ::s I. Q) <0U .., ... c... U

0 0 0 0 0 00

..,.,0

..,., 0 ..,.,- "" "" M M

0.-l

'"'"'.geo0.I/)o0.Q)...l

o 0..,.,

15

A M PHI B I ANS

Urodeles, on the other hand, which are today essentially

north temperate in distribution, appear to have originated

in Laurasia, the northern part of Pangaea. Only the

anurans are world-wide, which may indicate an early origin

or a greater capability for dispersal than either the

apodans or the urodeles have shown.

Most classifications of the modern Amphibia place them

together in the subclass Lissamphibia which implies that they

had common ancestry subsequent to the origin of the class

Amphibia. Significant differences in vertebrae and other

structures and the distribution of the three groups, however,

strongly suggest separate origins within the Amphibia. The

use of the taxon Lissamphibia, therefore, seems unjustified,

a view supported by R.L. Carroll and R. Holmes (1980) 'The

skull and jaw musculature as guides to the ancestry of

Salamanders', Zoological Journal of the Linnean Society,

ll, 1-40.

la teral views

ichthyostegalianlabyrinthodont

(Upper Devonian)

microsaur ianlepospon~'

(Lower Permian)

neural arch

pleurocentrum

intercentrum

neural arch

Icentrum l formed byossification around

the notochord

notochord

labyrinthodont and lepospondyl vertebrae

16

A M PHI B I ANS

Class Amphibia

Tetrapoda in which:-

• 1. The skin typically lacks scales. Epidermal glands

are present keeping the surface moist for cutaneous

respiration. (19)

• 2. The head is carried on a single cervical vertebra (20), the

atlas, which articulates with two condyles on the skull.

3. The brain differs little from that of fishes. There

is no neopallium, the midbrain is not covered by the

cerebrum and there are two optic lobes. (23)

• 4. The lower jaw consists of a maximum of three bones and

the ossified Meckel's cartilage, which forms the articular.(39)

Articulation with the skull is between the articular and

the quadrate. There is a single auditory ossicle, the

columella auris, homologous with the hyomandibular of

fishes. A superficial ear drum (tympanic membrane)

is present in most anurans, but the hearing apparatus

is degenerate in others and in all urodeles and apodans.(24)

5. Many Amphibia produce distinctive sounds.

6. Teeth are typically present on the jaws and the bones

of the palate and tend to be small or degenerate, but

may be absent. The jaw teeth are without sockets and

typically pleurodont (attached to the side of the jaw),

homodont (uniform) and polyphyodont (replaced many times).(21)

7. The buccal cavity has no cheeks and no secondary palate.

A well-developed and sometimes extensible tongue is

present in the majority of amphibians. (20)

8. The limbs are laterally orientated. They are modified

for jumping and swimming in the anurans, reduced or

absent in some urodeles and lacking in all apodans. (10)

9. The long bones and vertebrae lack epiphyses.

10. The heart has two atria (incompletely separated in some

urodeles and apodans) and a single ventricle. Pulmonary

and systemic circulations are thus only partially

separated. Both right and left aortic arches are

complete and functional. The erythrocytes are

nucleate, biconvex and oval. (26, 27, 28)

17

A M PHI B I ANS

11. There is no diaphragm separating the thorax from

the abdomen •

• 12. The egg is relatively small without a shell and there

is no development of embryonic membranes (amnion,

chorion, allantois). In the majority of amphibians

the egg is laid in water or in a moist environment,

fertilisation is external and the fertilised egg (and

embryo) is protected by a capsule of jelly. But some

amphibians are ovoviviparous and sperm is transferred

directly or indirectly from the male to the female .

Parental care occurs in a number of species. There

is typically a larva which may or may not be free­

living and metamorphoses into the adult. (19)

13. They are cold-blooded and there appears to be no

thermoregulation except by avoidance of extremes.

AMPHIBIA -------(

URODELA

APODA

newts & salamanders

caecilians

PROANURA (extinct)

ANURA frogs & toads

18

A M PHI B I ANS

out er s wo l len jel l y

i nner je l ly capsu leegg be f ore f ertilisa t ion

unswollen

";;;:1~:::::1n,ve getal membran e + -l\_~

pole

egg after f ertilis a tion

the a mphib ian e gg

stra tum c orneum

ve s s el

mucus gla nd

----- -------

- o ---~blOOd

--------- -

-__ con nective tis sue--diagram of a transve rse section of a mph i b ian skin

19

pin

eal

bo

dy

H:>­ 3: -e :I: co H :>­ z Ul

vert

eb

ra

med

ull

a

cere

bell

um

op

tic

lob

e

_----

trach

ea

-J..

.L.3

r--;

;~;;

:":;

"=":-L-'

-..-".

--:-,..-.----

vo

cal

sac

~----

stern

um

hy

oid

ton

gu

e

cere

bra

Ih

em

isp

here

olf

acto

rylo

be

nasal

sac

man

dib

le

ex

tern

al

nari

s

f{~

inte

rnal

nari

s\:'I:;:::r~

~'::

-'I..

..., o

glo

ttis

vo

cal

co

rd

eu

sta

ch

ian

tub

e

sag

itta

lsecti

on

of

the

head

of

an

an

ura

n

in

te

rn

al

naris

pre

vo

mer

(vom

er)

pala

tin

e;.- 3:

pte

ryg

oid

.." :::ecto

pte

ryg

oid

H Cl

para

sph

en

oid

H ;.-

basio

ccip

ita

lz fJ

l

con

dy

les

quad

rate

tabu

lar

~...

'1

1.

I

&:k\

la:~

;;~a

l_

•fr

on

tal

pre

fro

ntal

orb

itm

ju

ga

l

po

stf

ro

nta

l

If-A

-ti

-p

osto

rbit

al

~su

prat

empo

ral

squ

am

osa

l

Iq

uad

rato

jugal----H

N~remaxilla

,..<'<:

i1

nte

rna

sal

exte

rna

ln

aris

par

ie

tal

'I11

F-{+

.1

If\

pa

rl.

eta

yj~,

fo

ram

en

N ...

po

stp

arie

tal

do

rsal

vie

wth

es

ku

ll

of

aCarb

on

ifero

us

bas

ed

on

Megalo

cep

halu

s

pala

tal

vie

w

pari

eta

l

sup

rate

mp

ora

lI

po

stf

ro

ntal

tab

ula

rf

ro

ntal

pref

ro

ntal

co

ron

oid

2

arti

cu

lar

H> 3: -e :I: Cl> H > Z 1./l

co

ron

oid

sple

nia

la

ng

ula

r

co

ron

oid

3p

rem

axil

la

la

ch

ry

mal

sple

nia

larti

cu

lar

N N

sura

ng

ula

rd

en

ta

ry

pr

ea

rtic

ula

r

an

gula

r

po

sts

ple

nia

lin

ter

na

las

pect

of

lo

wer

jaw

lat

er

al

vi

ew

th

esk

ull

of

aC

arb

on

ifero

us

am

phib

ian

ba

se

do

nM

egalo

cep

halu

s

A M PHI B I ANS

thalamen_cephalon

hypophysis

ventral fissur e

-4.".....",.- infundibulum

medulla ---"'\

spinal cord

laminat e rmina I is --t-::-;i'i:::"'-=-4-­

optic nerve --+-""""::'-..

~L-_-":;;""'-- cerebellum

pineal body --.4:=::::::0'-1

dorsal view ventral view

cerebra Ihemisphere

optic lobe

olfactory lobe

olfactory nerve optic

pinealbody

medulla

spinal cord

) pituitary body

optic chiasma

lateral view

the amph ibian brain

23

A M PHI B I ANS

semieireular eanals

auditory nerve

bueeal eavity

pleetrum

""'F.~~_tympaniering

tympaniemembrane

eolumella(stapes)

middle eareavity

eustaehiantube

the anuran ear

24

mandible

A M PHI B I A N S

l ungs of a n aquaticurodele wi thout a lveoli

lungs o f a ter restria lurodele with i nc ipient alveoli

lung s o f a n a nura nwith a l veol i

25

A M PHI B I ANS

interna I gill externa lcarotid

i nterna Ic a r o t i d

-----

l eft auricle

e x ter na l gil l

t1---~~--- pulmonary ve ins

h:L.---- l eft systemic ar-eh

.,......-----4jI-....--- ventr i cle

ij ----oH--- pulmonaryar t ery

r i gh t a uricle

s i nu s venosus----~~~r

v e nae cava e ------~~y-

I

,... '" 11o v", J:V 0

.... t.t. Ol IIIv 0"' ....

..... +'Ol t. IVc 0

.... Ol

.~ ><t. .... Vo '"

VI

dorsal aorta -----------1

d ia gram of the h eart and aortic~r~~es of a urodele larva

26

A M P H I B I ANS

externalca rot id

i nter na Icarotid

I - - - - - ",..----

dorsa l aorta

interna I gi l l

pu lrnonary veins

l e f t auricle(septum i n complete)

ductusarteriosus

'd.----H--- pulmonaryartery

--- ---

w..--- ----H--- ventr icle

/-,L------ l e f t systemi c arch

v

VI

IV

III

II""' f/)o l1lf/)..cl1l t.)

..... I:.I:. ('j

l1l cf/) . ....

... .;.1('j I:.<: 0.... ~

.~ ><I:. .....o f/)

sinus venosus ----".",,-~­

ve na e ca vae --------""""""""''::f~

right auricle --"'"'----7

conus ----+t--------iarteriosus

diagram of the h e a r t a nd aorticarches of a u rode le

27

A M P H I B I A NS

e xterna lcarotid

i nterna lca r otid

ventric le

l e f t auricle

c arot id 19la nd l

pu lmonary veins

s u bc la via n--....,'-- a rte ry

left systemic arch

~----

-----

~;:v.--+l,----mu s c ul ocut ane ou sI ....~-"'...-::;.,.. a rtery

O'----;-r--- pu lmona ryartery

--- -- ....I

""' 00o Q)Iroo ..c:

Q)'(,).... .... ClI IrIQ) o00 ....

.... .., I VClI ..c 0

. ... ClI

.~ >< V.. ....o 00

VI

r i gh t auricle ---'t'r-----l

sinus venosus -----~~~~

venae c a va e --------->O'i!"<;.-<T

conus arter iosus -++-------..,11(with spira l vo lve )

d or sal aorta -----------1

d i a gram of the he a r t a nd a ortica rches of an a nuran

28

4 Newts andSalamanders

The newts and salamanders and their allies, which

comprise the order Urodela, have an elongated body, a

long tail and, in most cases, two pairs of limbs of about

the same size. In these respects they resemble the

extinct labyrinthodonts and lepospondyls.

Diversification of reproduction and larval development

is the key to the adaptive radiation of the modern Amphibia .

We know nothing of the reproductive methods of the early

Amphibia, except by implication from modern forms, but

it is assumed that the laying of relatively unprotected

eggs in water or wet places was an essential feature and

one which separated them from the reptiles. In common

with other modern amphibians, the great majority of the

urodeles still reproduce in this way. However, one

major group, the Salamandroidea, has interna I fertilisation,

though only a few species retain the developing e mb r yo in

the oviduct of the female. Among urodeles there are some

that are totally aquatic and others highly terrestrial in

the adult form. Aquatic forms live in s t r e a ms , lakes,

marshes and even in subterranean waters, for example

Proteus is found in caves in Yugoslavia. Terrestrial

forms may live in the earth, under stones, or in trees, as

in the plethodontid salamanders of tropical South America

which live and reproduce in plants of the pineapple family,

Bromeliaceae. Most are restricted to wet places, but

one form, Ambystoma tigrinum,thrives in arid lands of the

U.S.A. and Mexico . However, many urodeles are a mph i b i ous

and live equally weIl on land or in water. Where the

evolutionary advantage lies in being aquatic, an amphibian

29

N E W T SAN D S A L A MAN DER S

can become so by bringing sexual maturity forward into

the aquatic larval state. This is a phenomenon known

as paedogenesis and is common among urodeles. The

'axolotl' is the larval stage of A. texanum and in this

state can become sexually mature, so that some features

of adult structure never appear. Other urodeles such

as Proteus and Necturus have become permanently committed

to this paedomorphic state and the classification of the

group is based to a large extent on the degree to which

larval characteristics have been retained in the adult.

The reverse condition, that is the abolition of the free­

living aquatic larva to give a more fully terrestrial

animal, also occurs, particularly among plethodontid

salamanders.

The distribution of the urodeles is of particular

interest. It is essentially Holarctic and is discontinuous

and therefore relict. Urodeles, in general, favour cool,

wet places. One species of Hynobius penetrates the

Arctic Circle in Siberia and one tribe only, the

Bolitoglossini of the family Plethodontidae with 132

species in South America, has invaded the tropics. No

urodeles are known from the southern temperate regions.

Mexican axolotl

30

N E W T SAN D S A L A MAN DER S

Order Urodela

Amphibia in which :-

• 1 . The tail is weIl developed in the adult. The

postsacral vertebrae are not fused to form a

urostyle or coccyx.

2. The neck is more or less distinct .

• 3 . The hind limbs (when present) are similar in

length to the forelimbs . The radius and ulna

are not fused; nor are the tibia and fibula .

The tarsal bones are not elongated. Pectoral

and pelvic girdles are simple . The iliac part

o f the pelvic girdle (when present) i s not greatly

elongated. (34)

4. The eyes are relatively small, but functional,

with or without eyelids which may be movable .

5 . There is no tentacular organ .

6 . There is no tympanum •

• 7. The frontal and parietal bones are not fused and

the skull is not completely roofed by bone. (33)

8. The centra of the vertebrae are formed by the

deposition of bone around the notochord without

ca r til a g i nou s precursors .

• 9 . The presacral vertebrae are numerous (more than

30 to as many a s 100), that i s , the trunk is not

s hor t e ne d .

10. The larynx i s poorly developed and there is no

voice .

11 . The left lung is smaller than the right, but i s

functional, except in the Plethodontidae which

are lungless. (25)

12. Fertilisation is external or internal; reproduction

oviparous or ovoviviparous .

3 1

N E W T SA N D S A L A MAN D ER S

ORDER SUPERFAMILY

r-cr yptobranChida e

CrYPtobranChOidea~

Hyn ob i ida e

Salamandridae

Aphiwnida e

URODELA ----f--Salamandroide a ----t----Proteida e

Ambystomatida e

Plethodontidae

Sirenoidea --------Sirenidae

32

N E W T SAN D S A L A M AN DER S

qua dra toj uga l

s quamo sa l

-+ pt erygoid

!__-\- fr ont al

-4,._---".------- p r e f r onta l~ maxilla

premaxilla

....J~,._-----._---_ nasal

qua d r ate

--- e x o c c i p ita l

par ietal

fron tosquamosala rch

do r sal view

maxilla ---------{

qu adratoj u gal

quadra te --------....

~,._-------_ premax i lla

+ palat ine

interna 1 naris

orbitospheno i d

pt e ryg o id

e x o c cipita l

para s pheno i dpala t al v i e w

skull o f Tylototr iton, the primit ive salamandrid fromYunnan, the eastern Himalayas and Okinawa I sland .Note the complete upper j aw formed by t h e junction ofthe maxilla and quadrate by the small qu adratojugal a n d

also the fronto squamos al a r c h

33

N E W T SAN D S A L A MAN DER S

coracoid procoracoid

s t e r num

pectoral g i r d le of Ambystoma fr om the ventral a s pect

ypsiloid cartilage (epipubis)

ischium

pelvis of Tylototr itonfrom the ventral aspec t

34

pelvis of Cryptobranchusfrom th e ventral aspect

N E W T SA N D S A L A MAN D ER S

Superfamily Cry ptobranchoidea

Urodela in which:-

1- Hind limbs are present i n t he adult. (36)

• 2 • The premaxillary spines a re s hort a nd do

not separa te the na s a Ls , ( 39)

• 3 • The angular and prearticula r bones of the

lower j a w are no t fused . ( 39 )

4. Fertilisation i s ext ernal. Spermatophores

are not formed (exc ept in Ranodon ) a nd the

complex of cloacal g l a nd s contributing in

other urodeles to s pe r ma t o phor e forma tion is

represented by a single type of g l a nd . The

female has no spermatheca for storing sperm .

The eggs a r e l a i d in gelatinous sacs .

SUPERFAMILY

-{

c r y pt ob r a n c h i da e

Cr yptobranchoidea

Hynobiida e

35

giant salamanderand hellbende r

Asiatic landsalamanders

N E W T 5 A N D 5 A L A MAN DER 5

Family Cryptobranchidae - giant salamander, hellbender

Cryptobranchoidea i n which :-

1. The limbs are of moderate size with four

finger s and five toes .

2. Te eth are present in the upper and lower jaws

• a nd a s transverse rows on the prevomers, but

not on the parasphenoid. The skull is

flat tened . (39)

• 3 • There are no eyelids .

4. The a du l t has no e xt e r na l gills and gill

openings are reduced to a single pair

(Cryptobranchus) or are absent (Andrias).

5. Lungs are present .

6. These giant aquat ic salamanders are found in

the ea s ter n U. S . A. (Cryptobranchus) and in China

and Japan (Andria s) . There are 3 species i n

2 ge ne r a .

Examples: - Cryptobranchus, Andrias .

hellbender - Cryptobranchus

36

N E W T SA N D S A L A MA N DER S

giant sa la mander - Andr i a s

37

N E W T 5 A N D 5 A L A MA N DER 5

38

'"uQ)s:..,""'oeo......,:3.c....'"..,Ul....-e

W '4J

pre

max

ill

a

'<maxilla~

na

sal

pr

ef

ro

nta

l

je

\\

fro

nta

l

ex

occip

ita

l

do

rsal

vie

w

pr

ema

xill

a

par

asp

he

no

id

pa

la

ta

lv

iew

pre

vom

er

de

nta

ry

an

gu

lar

----

---1

1

pr

ear

ticu

lar---4

J

do

rs

al

vi

ewo

flo

wer

jaw

Z t'l

~ .., C/J > z o C/J > e­ > :3: > z o t'l

;>;l

C/J

sku

ll

of

Cr

yp

tob

ran

ch

us

N E W T SAN D S A L A MAN DER S

Family Hynobiidae - Asiatic land sa lamanders

Cryptobranchoidea in which :-

1 . The l i mb s are relatively l a r ge with four

finger s and typica lly five toes, but t he

f i f t h toe is lost in some species.

2. Teeth are present in the upper and lower jaws

• and on the palate i n a V-shaped or curved

formation on the prevomers bu t not on the

para sphenoid. The skull is not f lattened. ( 41)

• 3 . Movab le eyelids are present.

4. The adult has no external gills or in one

species only rudiments t hereof and no gill

openings.

5 . Lungs are typica l ly present , but ma y be

reduced or absent in mountain stream forms

(Onychodactylus).

6. These l a nd - l i v i ng salamanders occur in central

and eastern Asia .

5 genera.

There are 30 species in

Examples:- Hynobius, Ranodon, Onychodactylus.Batrachuperus.

Siberian sa lama nde rHynob i~

40

"

N E W T 5 A NOS A L A MAN 0 E R 5

~~~~~...---------- premaxilla

~ maxilla

-"~~------- pre vome r

+---H----- s phenet hmoid

1------- pteryg o id-+--'.;,-1-+----- pa rasphenoid

'}-.,!- qua dr-a t.o

l-r-r-r-r-r-r-r-r-r-r- pro o t i c~,,----- stapcs

e xocc i pita l+ o pi s tho t i c

condy le

pala t al view o f t he s k u l l of Ba t r a c huperus

d istribut ion o f t he Hyno b i ida e

41

N E W T SAN 0 S A L A MAN 0 E R S

Superfamily Salamandro idea

Urodela in which:-

1 • Hind limbs are present i n the adult . (44)

• 2 • The premaxillary spines are typically long

a nd s e pa r a t e the n a s a Ls , (4 3)

3. The a ngul a r a nd preart icular bones of the

lower jaw a re fused. (4 3)

• 4 . Fertilisation is internal. Spermatophores

a re formed by a complex of cloacal glands

of t h r e e types . The female has a

spermatheca for storing s per m. The eggs

a re not l aid in gelatinous sacs .

SUPERFAMILY

Salamandrida e

Aphiumidae

newts ands alamanders

Con go eels

Salamandroidea-------------+--Proteidae

Ambystomatidae

Plethodontidae

42

olm andmud-puppy

mole salamanders

lunglesssalamanders

N E W T SAN 0 S A L A MAN 0 E R S

premaxilla

dorsal view

external naris

nasalprefrontal

maxilla

+----\-1r------- frontal

pterygoid............L-+------- parietal

quadrate~......------- squamosal

\.'C=Y~~t:i~=======~e~x:o'CCiPital, condyle

premaxilla

quadrate

stapes

exoccipitalcondyle

maxilla

l------- pterygoid

+~~ prevomer

internal naris

para sphenoid

palatal view

dorsal view oflower---i a w

Ilr--------- dentary

44---- angular +prearticular

skull of Salamandra

43

N E W T SAN D S A L A MAN DER S

Family Salamandridae - Newts and Salamanders

Salamandroidea in which:-

1. The limbs are weIl developed with four fingers

and four or five toes.

2. Teeth are present in the upper and lower jaws

• and on the long, posteriorly directed horns

of the prevomers where they form long rows,

sometimes S-shaped, one on each side of the

para sphenoid. There are no teeth on the

parasphenoid. (43)

• 3. Movable e ye l i d s are present in the adult.

4. The adult has no external gills or gill

openings.

5. Lungs are present.

• 6. The sides of the body are not marked with

vertical costal grooves.

7. The eggs are laid in,water or in some species

develop in the oviduct of the female.

8. These mainly aquatic salamanders are also

found in moist places on land in North America,

Europe, North Africa and Asia. There are

42 species in 15 genera.

Examples:- Salamandra, Triturus, Molge,Ty l o t o t r i t o n .

marbled newt - Triturus

44

)

N E W T SAN D S A L A MAN D E R S

45

Q)<1l'tl....t.-ec<1lE<1l

.-i<1lin

Q)

..c:..,""'0

c0......,

I ~.0....s,..,l/l....-e

N E W T SAN D S A L A MA N D ER S

Family Amphiumidae - Con go eel s

Salamandroide a in which :-

• 1. 60th forelimbs a nd hind limbs a re r educ ed

and have t wo or three f ingers o r toes.

2. Te eth are present in t h e uppe r a nd l ower

• jaws and i n l on gitudinal row s o n the l o ng

prevomers. There a re no t eeth on t he

parasphenoid. (4 7 )

• 3. The r e a r e no eye l i d s .

4. The a dult has no e xte r na l gill s and o ne pa ir

of g i l l openings in front of the fo relimbs .

5. Lungs are present.

• 6. The sides of the body are marked wi th verti cal

costal g roove s .

7 . The e ggs are l aid i n water.

8 . These a quatic , eel- l i ke salamanders a re found

in stagnant waters a nd swamp s in t he Southe a s t

Unite d St ate s. There a re t hree s pec ies i n

a s i ngle genus .

Example:- Amphiuma.

d i s t ribut i on oft he Amphiumi dae

Congo ee lAmphiuma

46

N E W T 5 A N D S A L A MAN D ER 5

otoccipita l -----~,--"-e-I

pala t a l view

premaxil la

+..- na s a l

\- ma x Ll L a

++ pre f rontal

frontal

r"Ir------- quadra tev....,.,:::,,q'------- pterygoid

-J~-------squamosal-,;:~ parieta l

L.j.--------- otoccipita l

/L<fVI~r--------- premaxil la

l,\------------ maxi l la

p r e v ome r

4.JCW------- para sphenoid\- s p hene t hmo id+ pterygoid

1..,1 o coccLp Lt.a L

-f-------- qua d r a t e

""'\,+J.'---------- stapes

,-...\}-------- squamosa 1_ ~ otoccipital

skul l of Amp hiuma

47

N E W T SAN D S A L A MAN DER S

Family Proteidae - Olm and Mud-puppy

Salamandroidea in which:-

• 1. The limbs are present but small and have four

fingers and four toes (Necturus) or three

fingers and two toes (Proteus).

• 2. Teeth are present in ~he upper jaw on the

premaxilla (the maxilla being absent) and in

the lower jaw. The prevomers and palatopterygoids

bear teeth, but not the para sphenoid. (49)

• 3. There are no eyelids.

• 4. The adult has three pairs of external gills

and two pairs of gill openings.

5. Lungs are present.

• 6. The sides of the body are marked with

vertical costal grooves.

7. The eggs are laid in water or, in Proteus,

may be retained in the oviduct of the female .

8. The European olm (Proteus) is restricted to

subterranean waters in Yugoslavia while the

mud-puppies (Necturus) are found in the

eastern half of the United States and the

Canadian lakes.

two genera.

There are 5 species in

Examples:- Proteus, Necturus.

European olm - Proteus

48

N E W T S A N 0 S A L A MAN 0 E R S

~ premax illa

~~___________________ pre vomer

-1r-+-~~-----------pa rasph e n o id+- pa latopter ygo i d

+- quadrat e

//;'- squamosa l

-Cr1J-iI-------------- proot i c

J---------------- s ta pe st--1""i~------------- s quamo sa I

.........v.......~------------- 0 p i s t h 0 ti c

exocci pita l

palatal vi ew o f the s k u l l o f Ne c t u r us

d i str ibution of t he Prot e ida e

49

N E W T SAN D S A L A MAN DER S

Family Ambystomatidae - mole s alamanders

Salamandroidea in which:-

1. Both forelimbs and hind limbs are relatively

large with four fingers and five toes.

2. Teeth are present in the upper and lower

• jaws and in transverse rows or a r c he s on the

prevomers. There are no teeth on the

parasphenoid. (5 2)

• 3. Movable eyelids are present in the adult .

4 . The adult has no external gills or g i l l

openings, but paedogenic forms with external

g i l l s (3 pa irs) are common in local populations

and include the permanently larval Mexican

axolotl. The axolotl becomes a t ypical

Ambystoma when induced to metamorphose. (30)

5. Lungs are t ypically present.

• 6 . The sides of the body a r e marked with vertical

costal grooves .

7. The eggs are laid in water.

8. These land-living salamanders and their

aquatic paedogenic forms a r e found only in

North America. There are 32 species in

4 g e ne r a .

Examples:- Ambystoma, Dicamptodon,Rhyacotriton, Rhyacosiredon.

distribution of the Ambystomatidae

50

N E W T SAN D S A L A MA N DER S

mole sa lamanderAmbystoma t e xanum

( adul t of t he a xo lot l )

marbled s alamanderAmbys toma op acum

51

do r s al v i e w

N E W T S AN 0 S A L A MA N 0 E R S

premaxilla

e xte r na l na r is

septoma x i l la

nasalpre frontal

maxillafrontal

pt eryg o id

parieta lproot1.c

....,j~I----- s qua mosa lquadr ate

e xoccipita l

foramen ma gnum

premaxilla

teeth ---------f.:u--~~::....

....lX"~--------prevomer

internal naris

maxilla

\------- pterygoid-\--l--\----- s phe nethmoid

V:T----lo-- prootic

~----- qu adrate

exoccipita l

pala t al view para s phenoid

s kul l o f Ambys t oma

52

N E W T SA N D S A L A M A N DER S

Family Plethodontidae - lungles s s a l ama nde rs

Sa l a ma nd ro i dea in which: -

1. 60th fo relimb s a n d hind l imbs are of modera t e

siz e or ma y be r educed. There a re t ypically

four finge rs and five toes .

2 . Teeth a re pr e s e nt i n t he u pper a nd l ower j a ws

• and typica l ly on t he palate , a nterior ly i n

t r a nsverse r ows on t he pre vomers and a lso o n

plates of vomer i ne origin c overing t he

para sphe no id. (54, 55)

• 3 . Mo vable eyelids are pr e s e nt in the a dult.

4 . The a dult has no externa l g i l ls (except i n

Typhl omolge ) a nd no gi l l o pe nings .

• 5. They have no lungs, r ely ing on cuta neous

r e spira t i on •

• 6 . The sides of t he body are ma r k ed wi th ve r tic a l

costa l g rooves .

7 . The eggs are l aid in water or on l a nd .

8 . These are ma inly aquati c salamanders bu t

i nc l ude some terrestria l a nd a r borea l fo rm s.

They o c c ur i n t he New World except fo r species

of Hydroma ntes fou nd in southeast Fra nc e,

I t al y a nd Sa r dinia . There a re 19 4 s pecies

in 23 genera .

Example s:- Ple thodon , Ty ph lomol ge , Eurycea ,Hydr oma n t e s, De smogna thus.

r ed -backed salamanderPlc thodon c i nereus

N E W T SA N D S A L A MAN DER S

d i stribut i on of t he Ple thodont idae

fron t al

pre fr o n t al

na sa 1 ------7'''''''pr emaxil l a

septo ma xi l la

max illa

par i e t al

condyle

7"'::-,.--,f'C-- s qua mo sa 1e x occipita l

~------- quadr at e

d ent ary para sphenoid

p re vomer prearticular + angular

l a teral v iew o f the s k u l l of Eurycea ö

54

N E W T SAN D S A L A MAN DER S

premaxilla

(not e a b s e n c e o ft eeth on prevomer)

""'~~ prevomer

\-- maxilla

para sphenoid

pterygoid

t e e th

qu adra te

r---------- e xoccip i t a l

palatal v i ew o f Desmogna thus 0

.A:t:7'~:.,.,---------- premaxilla

.....;I,-~--------- pr- e vom e r-

maxilla

1------- p t erygo id

~r-----,H-------pa r-a s phen o i dwith teeth

quadrate

palatal view of Plethodon

55

N E W T SA N D S A L A MA N DER S

Superfamily Sirenoide a

Ur odela i n whi c h :-

• 1. Hind limbs a re absent •

• 2 . Th e premaxillary spines a r e s hort and d o

no t s eparat e t he nasal s . (5 8)

3. The a ngul a r a nd preart i cula r b on es of t he

l ower jaw a re fused .

4. The manner o f fe r t i l isat ion i s no t kn own,

b u t t he male s l ack t he c loa ca l g lands f o r

the formation o f s permatophores a nd t here

i s no s permat heca in t he f emale f or t he

storage of s per m, s uggesting e xter na l

fe rti lisation . On t he other hand t he eggs

a re l a i d singl y a nd attached to t he r o ot s of

wa t er plant s a nd are widely scattered which,

b y ana logy with other urodele s t hat l a y

single eggs, sug ge s t s i nternal fe rt i lisation .

SUPERFAMILY

Sir enoide a ------------ Si r e nida e s i rens

_ -. . - - '- .. _----- - - "-- " -'"

........_.-.- - ----~- .- ..........

Siren

56

Plate 1 Mud-puppy, Necturus maculasus (Proteidae page 48), eastern U.S.A .(Zoological Societv of London]

Plate 2 Olm, Proteus anguinus (Proteidae page 48), eastern Adriatic seaboard ,north to Istra south to Montenegro. (Zoological Societv of Lenden]

Plate 3 Axolotl, paedornorph ic larval form of Ambystoma (Ambystomatidaepage 50), U.S.A. and Mexico. (Zoological Society of London)

Plate 4 Tiger salamander, Ambystoma tigrinum (Ambystomatidae page 50),U.S.A . and Mexico. (Zoological Society of Londonl

Plate 5 Siren, Siren lacertina ISirenidae page 57), south -easrern U.S.A .(Zeelegical Seciety of Lenden)

Plate 6 Yellew caecilian , Schistometopum thomeuse (Caeciliidae page 68) ,Säe Terne, Gulf of Guinea. (Zeelegical Societv ef Lenden)

Plate 7 Midwife toad, Alytes obstetricsns (Discoglossidae page 961. Europe.Male toad carrying eggs. (Zoological Societv of London)

Plate 8 Surinam toad, Pipa pipa (Pipidae page 99), tropical South America .Female toad carrying eggs. (Zoological Societv of London)

( 1/

Plate 9 Clawed toad, Xenopus gilli (Pipidae page 99), Cape region of SouthAfrica. A rare and endangered species of this African genus .lR. C. TinsleyJ

Plate 10 Southern spadefoot, Petobstes cultripes (Pelobatidae page 106),western and southern France and Spain, (Zoological Societv ofLondon)

Plate 11 Horned bull toad , Megophrys nasuta (Pelobatidae page 106), Malaya.(Zoological Societv 01 Londonl

Plate 12 Horned bull toad, Megophrys nasuta (Pelobatidae page 106), Malaya.Toad in leal litter showing camouflage. (Zoological Society ofLondonl

Plate 13

Plate 14

Common Asiat ic toad, Bufo melenostictus (Bufonidae page 116).tropical Asia, Malaya . (Zoological Society of Londonl

Darwin's dwarf frog, Rhinoderma darwinii (Leptodactvlidaepage 120), Argent ina . (Zoological Societv of London)

Plate 15 Tree -frog, Hyla punctatissima (Hylidae page 1241, Brazil . Noteconvergence with the rhacophorid below. (Zoological Society ofLondon)

Plate 16 Tree-frog, Rhacophorus leucomystax IRhacophoridae page 133).Malaya and Indo-China. Note convergence with the hylid above .IZoological Societv of London)

N E W T SAN D S A L A MAN DER S

Family Sirenidae - Sirens

Sirenoidea in which:-

• 1. The forelimbs are short and have three

fingers (Pseudobranchus) or four (Siren). (56)

• 2. There are no teeth i n the upper jaw a nd only

patches of teeth o n the splenial bones of

the lower j aw. 80th j a ws are covered with

horn. The maxilla is minute. On the

palate the re a r e teeth on the prevomer and

palatine , but none on the parasphenoid. (5 8)

• 3. The eyes are very small and there a r e no

e yelids .

• 4. The a du l t has three pairs of e x t e r na l g i l l s

and one (Pseudobranchus) or three (Siren)

pairs of gill openings .

5. Lungs are pre s ent.

6. These aquatic, eel-like salamanders burrow

in the mud of d itches a nd ponds. They occur

only in the eastern United States and a d j a c e nt

northern Mexico. Ther e a r e three species

i n two genera.

Example s :- ~, Pseudobranchus.

distr ibution of the Sirenidae

57

N E W T SAN D S A L A MAN DER S

opisthotic + prootic

+ squamosal

-+>.- parietal

W,f->.,..\-------------- nasal-J.-\----------- frontal

sphenethmoid

111-.\\1...----------- premaxilla

exoccipital

palatal v iew

I"":r'T----------- premaxilla

,~...~lI------------ maxilla\.- prevomer

palatine

para sphenoid

}- quadrate

j,L--------- squamosal

• .,; fenestra ovalis

;-,r\~----- opisthotic + prootic

exoccipital

skull of Siren

58

5 Caecilians

The Apoda or Gymnophiona, commonly known as caecilians,

are a n obscure group of tropical forest amphibians. The

majority burrow in soft damp earth, though one family, the

Typhlonectidae, comprises riverine forms. Caecilians

resemble large e arthworms having a cylindrical body with

numerous transverse rings and no legs or tail. Because

of their habits they are seldom seen, but are possibly

not uncommon locally . There are 150 species in 20 genera,

widespread in the appropriate habitats in the tropics and

no doubt more will be discovered .

Among living amphibians the caecilians appear to have

retained the greatest number of primitive characteristics,

but at the same time they are highly specialised in

a c c or d a nc e with their burrowing mode of life. Many

caecilians have peculiar minute dermal scales resembling

those of the Microsauria from the Carboniferous period.

Unlike the Anura and Urodela, but in common with the early

amphibians, the caecilians have a skull that is almost

completely roofed with bone. This dermal bony covering

has often been held to be a primitive characteristic, but

it now seems probable that it was derived from the

remaining bones after a number of the skull elements had

been lost and is therefore a secondary structure. However,

some skull bones, such as the prefrontals and ectopterygoids,

not found in other living amphibians, have been retained

by certain caecilians and also link the group with the

Microsauria or a related early amphibian stock. Fossil

caecilians are almost unknown (there is one from the

Eocene Period), but the Permian lepospondylous microsaur,

59

C A E C I L I ANS

Lysorophus, judged from morphological evidence, may be

near the ancestor of the Apoda. Lysorophus was small

and wormlike and was probably aquatic. It had a

peculiarly modified skull which in many ways resembled

that 01 the caecilians.

Among apodan specialisation~on the other hand,must

be mentioned the unique tentacle situated beneath the almost

or completely functionless eye. All adult caecilians have

a pair of such tentacles which presumably are sensory and

in some way compensate for the 1055 of sight, a sense

which would be useless in burrowing. Reproduction, too,

has been modified for life in damp soil or rivers. All

caecilians lay large yolky eggs or are ovoviviparous

(Typhlonectes), but there is much variation in life history .

In some, such as Ichthyophis, the eggs are laid on land

and there is parental care by the female until they hatch

into aquatic larvae. In others there is no larval stage

and the juveniles emerge as replicas of the adult.

The pantropical distribution of the Apoda is of

interest in comparison with the essentially Holarctic

distribution of urodeles . Like them, the caecilians seem

unable to cross salt water so that their occurrence in both

the Old World and the New suggests an origin prior to the

break up of Pangaea, possibly not later than the Triassic.

The absence of caecilians from Madagascar is significant

since at the time of its separation from the African

continent in the Cretaceous per iod, Madagascar was barely

within the tropics (see Guide to Living Reptiles p .16).

If, as might be expected, the caecilians have always been

tropical forest animals, their absence from Madagascar can

be explained in this way. Moreover this also adds support

to the suggestion that the Apoda and the Urodela (and

probably the Anura as weIl) have entirely different

ancestries from among the early Amphibia.

60

C A E C I L I A NS

Order Apoda

Amphib i a in which :-

• 1 . The tail is greatly redu ced o r a b sent i n t he a du lt . (62)

2 . There is no d i s t inc t neck, t he head be ing e xterna l ly

• continuo us wi t h t he tru nk which ha s numerous

t ransverse rings . (68 )

• 3 . Limb s a nd gi r d les are a b sent a nd the body i s

worm-l ike . (68)

• 4 . The eyes are r educ ed and a re typ ically c overed b y

p i gment ed s kin or skul l bone s . (62)

• 5 . There i s a sensory tentacu lar orga n f rom t he s i de

o f the b rain prot ruding through t he o r bit or t hrough

a n a perture in fr ont o f and below t he eye . (62)

6 . There is no tympa num.

• 7 . The f ronta l a nd par ieta l bo ne s a re not f used a nd

t he s k u l l is a l most completely roofed b y b on e. (6 4)

8 . The centra of the vertebrae a re f ormed by the

depo s i tion of b one around the notochor d without

carti laginous pre cur s or s .

• 9 . Th e ver tebrae a r e numerous a nd ma y be as many as

2 50 .

10. There is no l arynx and no vo ice .

• 11 . The l eft lung i s typica l ly r udimentary and t he

right e xtended int o a cy lindrica l sac •

• 12. Fert ilis a tion is i nt ernal , the c loaca o f the male

f orm ing a pr ot ru s ible copulatory orga n . There

is no sperma the ca. Repr oduc t i on i s o viparous ,

ovovivipa r ous or vivi parous. (62)

Ty phlonectidae

Cae c iliida e

APODA ----------1I chthyoph iidae

Scolecomo r phidae

6 1

C A E C I L I AN S

r e duc ed eye

t e nta cula ro rga n

tran s ver s er ing

na ri s

he ad a nd anterior trunk of Caecilia

t ra nsverse -\ring

i ntromi ttent organ ~~

~terior end of Scolecomorphusshowing evert ed intromittent organ

62

no t e a b s e nceof t a i l

C A E eIL I ANS

prefront al f ronta l parietal

e xter na lnaris

premaxi l la

nasal orbit jugalquadra t e

se ptomax i l la

maxilla

post fr on t al arti c u la r

d entary s qua mosa l

tentacular groove

l a t eral view o f t he s kul l o f Ichthyoph i s

63

o­ .,.

pre

max

illa

"<-

sep

tom

axi

ll

a

,A~-------

nasal

-+-\

-p

refr

on

tal

.!r------

max

illa

~

.\-

__

te

nta

cula

rg

ro

ov

e

pre

vo

mer

~~

int

ern

a1

nari

sir

M.

orb

it(e

ye

soc

ke

t)

'L,

postf

ron

tal

I<.

pala

tin

e

~~

fro

nta

l

ju

ga

lp

tery

go

id;

Ipar

ieta

lp

ara

sph

eno

id./

.-.l

I..

--

sq

uam

osa

l

quad

rate

sta

pes

ex

oc

cip

ita

l'~

...'

co

nd

yle

-..

.-/

o :>­ m o H e­ H :>­ z Ul

do

rsal

vie

w

sk

ull

of

Ich

thy

op

his

pa

la

ta

lvie

w

C A E eIL I A N S

1I

IIIr..

.: 1;'­. ':: '1 '

I ,'::'1: .

I" : '.

.: ~

III

I

J,i I

' . I

<1l"tl0

...:Q)

..c...,q..,

")

0

c0.......,::l

.0....s,...,

~ <J)....-e

65

C A E C I L I ANS

Family Typhlonectidae

Apoda in which:-

1. There are no dermal scales.

2. There is no tail.

3. The eyes a r e distinct or concealed under

the skin. There is an eye socket.

4 . Septomaxilla, premaxilla and nasal bones

are present and s e pa rat e .

• 5. Prefrontal bones are present.

6. Astapes is present.

7. They are ovoviviparous .

• 8 . The young in the 'uterus' have bag-like,

external gills. There is no free-swimming

larval stage.

• 9. The adults live in s t reams and ponds and

have the posterior end of the body l aterally

flattened fo r swimming.

10. These aqua tic apodans a r e restr icted to

tropical South America . There are 12 s pe c i es

in 4 genera.

Examples:- Typhlonectes, Potomotyphlus,Nectocaecilia, Chthonerpeton.

probable distr ibution of the Typhlonectidae

66

dorsal view

palatal view

C A E C I L I ANS

__~~---------- external naris

~-------------------nasal

/«~ max i llaprefrontal

eye socket

frontal

+-----__ squamosal

parietal

<f---------- quadrate

exoccipitalcondyle

nasal

.....~+-------------- premaxilla

maxilla

-f~\---4f"c-----------prevomer

~~'--''A~-internal naris

-'t'lf--J~---------pa la t ine

-t----- pterygoid

quadrate

-t'---:::;"L------ parasphenoidstapes

)---------------- exocc i pita1

skull of Chthonerpeton

67

C A E C I L I ANS

Family Cae ciliida e

Apo da i n which :-

1. De r mal sca les may be present or a bsent.

2 . There ma y b e a short ta il or none .

3 . The eye is d ist inc t or concealed under t he

ski n or c r an i al bone s . There is a socket . ( 62)

• 4. There is no septomaxi l la a nd the pr ema x i lla

a nd nasa l are fuse d .

• 5 . There are no pr efr ont al bones .

6 . Astapes is pr e s ent.

7. They a re ovipa rous or ovo vi v i parous .

• 8 . The yo ung ha ve 3 pairs of branched g i l ls .

There ma y o r ma y no t be a fr e e - swimmi ng l ar val

s tage .

9. The a d ults are terrestria l a nd bur r owing.

10 . The f amily i s widespread in New World and Ol d

World tropics . There are 106 species i n

19 gene ra . (65)

Exa mple s:- Caecilia , Oscaecilia, Gymno phis ,Geotrypetes.

68

C A E C I L I ANS

Family I chthyoph i ida e

Apoda i n which : -

• 1. Derma l scales a re present . (70)

• 2 . A s hort tai l is present .

• 3 . The eye is relatively weIl de velo ped and ha s

a socket . ( 6 3, 6 4)

4. The se ptomaxi l la , prema xilla a nd na s al are

pre s ent a nd sepa rate . (63, 6 4)

• 5 . Pre fr o nt al b one s are present. (63 , 6 4)

6 . A s tape s is pre s e nt. (6 4)

7 . The y a re o viparous .

• 8 . There are f ree-swimming l arva e with 3 pairs

of branched gi l ls which a re soon l o s t, but

the l a rva r emains a qua tic for a l on g t i me

before me t a morpho s i s t ake s pla c e.

9. The a du lts burrow i n sof t , damp earth .

10. The s e ter restria l a po dan s ar e fou nd i n t he

New World tropics , S . E. Asia, t he Ph il ippi ne s

a nd t he Mala y archi pe lago . There are 43

s pecies i n 4 genera .

Examp l e s:- I chthyoph i s, Ca udaca e c il i a,Rh i na trema , Epi crinop s .

Ichthyoph i s l a r va

Ichthyophi sg ua r ding eggs

69

C A E eIL I ANS

single scale from Ichthyophis

"....• 0 Q~ . .. ." . ..-wG O

"" " ••• . ;= :.,'o . ' " , '."

o '. ' .. ' . . .--- --- -------------­': '. . ; ' ....

o ~'tJ

probable distribution of the Ichthyophiidae

70

C A E eI L I AN S

Family Scolecomorphida e

Apoda in which : -

1 . There a re no dermal s c ale s .

2 . There i s no ta i l.

• 3. Th e e ye s a re c ove r ed by b one or have moved

into a n a nter i or posit i on where t hey a re not

c o ve red . The tentacles a re ve r y l a r g e a nd

a s t hey grow t hey ma y c a rry t he eyes f orward

so t hat t hey a re displa c ed f rom u nder t he bo ne .

There i s no eye s ocke t .

4. The s ept oma x i l l a , pr emaxil la a nd na s al a re

present a nd sepa rate .

• 5. There are no pre f r on t a l bones .

6 . There is no stapes .

7 . Th e mode of r eproduction is proba bly

o vo vivi parous . (62 )

• 8. The e mbryos ha ve 3 pa irs o f large b r anching

g i l ls .

9 . The a dults a re ter restria l and burrowing.

10 . The f amily i s f ou nd o nly in central Afr i c a.

There are 6 s pecies in a s i ngl e genus .

Example: - Sco lecomor phus .

p r ob able d i str ibution of Scolec omor ph i dae

71

6 Frogs and Toads

The f rogs a nd toads are by far t he l a r ge s t group o f

t he living amphib ian s , world-w ide in t heir di s tr i bution,

apar t fr om polar a nd extreme de s ert a reas and some isol a ted

isla nds, and occupy a great r ange of habita t s. Yet

the fr og ( or t oa d ) i s one of the mo s t e as i l y r e c ognisable

of a l l vertebrate s. They are a l l quite obvi ously o f

r a the r s imi la r s h a pe a nd s ize, whe ther the y are ter restr ia l

o r aquatic , burrowing or arborea l , e ve n t hough t hey numb er

s ome 2500 or more s pec ies . Di f f erent s pe cies of fr og a re ,

of course , a da pted to live in ve ry d i f f erent e nvironments ,

but their a da ptations, with minor exceptions , i nvolve

phy s i ology, behavi our a nd pa r ticularly metho ds of r e product i on

rather t han e xter na l f e a tures. Th e Anur a a ppear to have

evol ve d a body f orm a nd s ize s uited f or survi val i n almo s t

a ny te r restr i a l e nviro nment whe r e s ome f r e sh water i s

a va i lab le fo r part of t he year.

The or igin of the Anura is as obscure as t hat of the

Apoda a nd Urode la . Their f ossil hi s t or y ca n be t ra ced

back to t he Tr iassic of Madagascar a nd t he J urassic of

So uth Ame rica and Europe . Th e Triassic Tr i adob a trachus,

Or der Proanura , was possib ly i ntermediate between t he modern

f rogs a nd sma l l l abyr int hodo nt s of t he Car boniferous Per i od

o f North America , s uch as Miobatrachus. The t r unk was

f airly l on g and carr ied a tail and relat i vely l ong l i mbs,

but t he s ku l l wa s very f rog- like. The Jura s sic fo r ms , o n

t he other hand, were c lea r l y fr og s o f modern build. The

South Ame ri can f orms Not ob atra chu s a nd Viera ella a re

r eferable to t he Leiopelma t ida e a nd the Europe an

Montsechobatra chus a nd Eodiscoglossus a re ear ly di s c oglo ssids .

72

fossil

to

th

em

odern

an

ura

ns

...., w

"~c;

:::::'

1II

\'u

]111

11

,,.

,I

•"'

11/

1& Ji~

"'<'~'

.::-....

/.>:.

...,.

'0.,J.,.

"'\~

tß?-#

Jf.O~l~ ~

..a

~o

<>.~

_~~

'-7/}

~'\~

q'

.

,.#4,

?"~":

>'\>"""

.#:

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~~•

"-,

." ;<l o C'l

Ul > z o ... o > o Ul

Mio

batr

ach

us

Carb

on

ifer

ou

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iod

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rth

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a

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dob

atr

ac

hu

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ria

ss

iePerio

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ad

ag

as

car

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batr

ach

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ras

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io

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ou

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meric

a

F R 0 G 5 A N D T 0 A D 5

It is reasonably certain that the origin of the Anura

predated the major break up of Pangaea and may weIl have

occurred in the southern hemisphere, the early frogs

spreading to colonise all suitable areas of the continental

land mass.

The general external similarity of frogs and toads,

the relatively large number of species and the fact that

there has evidently been much convergence among them has

raised continuing difficulty in the classification of the

Anura. Although modern classification is based on

phylogenetic principles so that closely related groups are

placed together and those held to be more distant genetically

are separated, the system must at the same time produce a

classification that is functional in terms of clear

recognition of the groups assigned to the different taxa.

So far as the Anura are concerned recognition of many of

the groups is far from clear, largely due to similarities

probably arising from convergence. The majority of the

characters used are interna I and there are serious doubts

about the phylogenetic significance of many of these .

Early classifications were based on such characters as

tongues, teeth, pectoral girdles and vertebrae, but there

have been many changes proposed as research has revealed

new characters and a better understanding of the old ones.

Moreover, improved knowledge of the fossil history of the

Anura in the late Mesozoic and early Tertiary and particularly

an appreciation of their distribution in the light of

continental drift, have provided new insight into the

evolution of the group.

The families of frogs divide into ancient frogs

(Archaeobatrachia) and modern frogs (Neobatrachia) with

three intermediate groups, the Aglossa, Rhinophrynoidei

and Pelobatoidei, thus recognising here five suborders.

The Archaeobatrachia comprise the Leiopelmatidae and the

Discoglossidae with clear Jurassic origin. The Pipidae

and Rhinophrynidae, the first being probably the older with

possible late Jurassic origin, are usually grouped together.

74

......

<.n

vi-.

\ /\

vv

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,

\r-

,

v~

~ \<,r-

, """

eq

ual

deg

rees

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olu

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ce

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iop

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ati

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lossid

ae

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ipid

ae

..., '1 0 aq

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ino

ph

ryn

idae

rn""

~;<

l

0P

elo

bati

dae

C'J

Ul

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fon

idae

r:>- zL

ep

tod

acty

lid

ae

I:' '"'l

Hy

lid

ae

0:l (1

):>-

:(

Ran

idae

I:'..., '1

Ul

0 aq tnS

oo

glo

ssid

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ori

dae

Mic

roh

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F R 0 G SAN D T 0 A D S

However, their matching characters are such that, with the

great difference in life style (pipids being wholly aquatic

and Rhinophrynus a desert, termite-eating form), it seems

they should be separated. The Pelobatidae are often

included in the Neobatrachia with the reservation that they

have a number of ancient characteristics. They seem to

be Cretaceous in origin and therefore it is probably better

to give them separate subordinal status. The Archaeobatrachia

and the three intermediate suborders, Aglossa, Rhinophrynoidei,

Pelobatoidei, are covered in this chapter and the modern

frogs, Neobatrachia, in the next.

SUBORDER

ARCHAEOBATRACHIA

AGLOSSA

ANURA ------------------~~RHINOPHRYNOIDEI

PELOBATOIDEI

NEO BATRACHIA

76

F R 0 G 5 A N D T 0 A D 5

Order Anura

Amphibia in which:-

• 1. The tail is absent in the adult and the postsacral

vertebrae are fused to form the urostyle or coccyx. ( 82)

2 . There is no distinct neck, the head being externally

continuous with the trunk. ( 20)

• 3. The hind l imbs are considerably larger than the

forelimbs and are used in jumping and swimming.

The radius and ulna are fused and so are the tibia

and fibula. The tarsal bones are elongated.

The pectoral girdle is complex ; the iliac part of

the pelvic girdle is greatly elongated and

articulates with the sacral diapophyses. (81, 82)

• 4. The eyes are typically large and have movable

eyeLf.ds , (78)

5. There is no tentacular organ.

• 6. The tympanum is typically large and prominent. (78)

• 7. The frontal and parietal bones are fused . The

skull is not completely roofed by bone. (79, 80 )

• 8. True centra of the vertebrae (formed from a r c ua l i a )

are reduced or absent. They are replaced

functionally by down growths of the neural a r c h e s

resulting in the chondrification and ossification

of the notochordal (perichordal) sheath. In the

t adpole the centra are represented by blocks of

cartilage. l8 8)

• 9. There are 5-9 presacral vertebrae, that is, the

trunk is greatly shortened. (82)

• 10. A larynx is usually present. (20) The voice is loud

and typically characteristic of the different species.

11 . Left and right lungs are present and similar in size.(25)

12. Fertilisation is typically external and reproduction

oviparous. Some species of Eleutherodactylus and

Nectophrynoides are ovoviviparous and others of

the latter genus are viviparous .

77

F R 0 G 5 A N D T 0 A D 5

eye a nd lids

Iexternal

t ympa num

he ad o f Rana

internal nar is

"~~-+eusta chian tube

" .-......~~~~~;=:=:d~==_o~:esoPhagUS~ e lottis

vocal sacopening

tongue

buccal c avity of a r anid

78

F R 0 G 5 A N D T 0 A D 5

premaxilla

maxilla

quadratoj uga l

\~--~~-- s qua mosa l

__~~~-------nasal~~~====~~~~-frontoparietal

\~H.---- pterygoid

for amen magnum

e xter na l

dor s al v i e w

sta pes .J-_\

otoccipital regionexoccipital---------~~

condyle

premaxilla

internal

frontopar i e t a l --t+---f--\-----,f-1

squamosal --->,k:r-r-

otoccipital

........,.-- maxilla

~::-~""':>'c------- prevomer

::::.---.::-r""---- pa l a t ine~----~~~--sphenethmoid

~~---pterygoid

+-,.i+--------lH~~'parasphenoid

quadratoj ug a l

--.!!...-===5>,.,c.t:S;-~Ij---_ prootic~I-'<---- qu adrate

....-;:--"7:::::.~-----:.stapes

~~-------exoccipital

palatal v iewcondyle

dia g ram of the a nu r a n s k u l lbased on Bufo

79

F R 0 G SAN 0 T 0 A 0 S

frontoparietal

otoccipital region sphenethmoid

external naris

exocciPital--------~~~~~;;~:::;:::b~~:ioccipita1 --------l;'--)..:~1~,J,f=~::::,:;=-~condylestapes v premaxilla

squamosa 1 --------------,u=---:::::a::=---==::::::::=----------- maxillaqua dra t e ----------------.J.:L._-

quadra tojugal pterygoidil'-.D--mentomeckelian

angulosplenial de nt a r y

lateral view

frontoparietal

otoccipital ~~~

region

stapes

squamosal pterygoid

quadrate para sphenoid

quadratojugal occipital condyle

posterior view

d i a g ram of the anuran skull base d on Buf o

80

F R 0 G S AN 0 T 0 A 0 S

metatarsal ------------~~l\\11

~\Uo -===== Phh:l~l:gXe s

calca r ----------O!:J~'!i

meta c arpal

g~OQ car pa ls

~... ". ac~t{caagnae~':ns

---- r adio-ulna

d eltoid ridg e . : ' - - olecranon proce s s

t i b iof i b u la ---------1

h u me r u s

f emur ----------1

r ight fo relimb o f Bufo

cart i lagi nous c a p ----.,.,:·:::1

r i ght hind l imb of Bufo

81

F R 0 G SAN D T 0 A D S

epicoracoid

clavicle

sternum

suprascapula

--,~~-cleithrum+---4';';"/--- scapula

pectoral girdle of Bufo

atlas vertebra

t-..:'-..j...--- transverse process

expanded sacraldiapophysis

urostyle

ilium

ischium

dorsal view of the vertebral columnand pelvis of Bufo

82

F R 0 G SA N 0 T 0 A 0 S

sacr um -------t-------s a c r a1 dia po phy s i s

urosty1e (coccyx ) --- - - - - - 4

mos t Archaeobat rachiamo s t Pe1obatoidei

Sooglossidae

sacra1 d i a pophy s i ssacrum-----.--f--~"""--~-

u rosty1e ( coccyx)-------~

Rhinophrynoideimost Neobat rachia

sacrum wi th di1atedd i apo ph y s e s a ndmon oc o nd 1a r a~ticu1ation

with t he u rost 1e cocc xl

sacrum wi t h cy1indrica 1d ia po po physes andbicondy1a r articu1ationwith the urosty1e ( c oc cyx l

• 1.

• 2.

• 3·4.

• 5 .

• 6.

F R 0 G SAN 0 T 0 A 0 S

Suborder Archaeobatrachia

Anura in which:-

The tongue is disc-shaped and typically cannot be

protruded.

The pupil of the eye is vertical or triangular.

The trigeminal and facial ganglia are separate. (85)

The parasphenoid has lateral alae . (86)

Free ribs are present associated with the 2nd,

3rd and 4th vertebrae. (87)

The centra of the vertebrae are ectochordal or

stegochordal. (88)

• 7. There are free intervertebral dises. (87, 89)

• 8. The epicoracoids of the pectoral girdle overlap

ventrally and the backwardly directed epicoracoid

horns are short and blunt and intersleeve with

sternal laminae. (87)

• 9. The scapula is overlaid anteriorly by the clavicle. (87)

10. In the thigh the m. sartorius and the m. semitendinosus

are not separated, except in Discoglossus where

separation is partial. (90)

11. Amplexus is inguinal. (91)

12. The tadpoles typically have denticles and beaks,

a single median, ventral spiracle and no barbels. (92)

Leiopelma completes development and metamorphoses

within the egg membranes.

SUBORDER

-{

Leiopelmatidae

ARCHAEOBATRACHIA

Discoglossidae

84

F R 0 G SAN D T 0 A D S

anterior

posterior

anterior

posterior

s:l

•.-lC<Ut.oot.'tlCoJ:o

E:l

•.-lC<Us,oot.-eCoJ:o

/'--------- trigeminal nerve(part)

ft-----jf---- facial nerve(palatine ramus)

,,'1-_'1'----- racial nerve(hyomandibular ramus)

trigeminal nerve(part)

\~--\l----#-----fa cia1 nerve(palatine ramus)

\~~~~~~----facialnerve(hyomandibular ramus)

+----\-- prootic ganglion

85

F R 0 G SA N D T 0 A D S

a l a +-Bomb i na

Rhino phrynus

a l a Lept oda c t y l u s

t he f or m o f t h e para s ph enoid i n different a nu r a nsshowing the pre s enc e or a bse nce of la t e ral alae

86

F R 0 G SAN D T 0 A 0 S

clavicle {overlapping scapula)

cleithrum

glenoid fossa

e pi cor a co i d

coracoid

sternum (epicoracoid hornsd o r s a l to sternum)

pectoral g i r d l e of As ca phu s

cartilaginous caps

ribs

transvers e processes

,c~q--- intervertcbral disc

sacral diapophysis

urostyl e (coccyx )

ventra l v i e w of the vertebral c olumn of Asca phus

87

F R 0 G SAN 0 T 0 A 0 S

ossifiedperichordal

s heath

e c tochordal c e n t r um

o s s i fie dperichordals heath a ndno tochord

holochordal c entrum

oss i f iedperichordal

s hea t h

r emains o fno t ochord

s tegochordal centrum

diagrams s howi ng the f orma tion of t h e c entrum in Anura

88

F R 0 G SAN D T 0 A D S

centrum of ver t e br a i nter vertebral disc

amphicoe lous vertebrae with fre e intervertebra l d i s c s

c e ntrum of vertebra i ntervertebral disc

ant erior

II

IIIII\\\ ,

posterior

p r o c o e l ous vertebrae with t he intervertebra l discsfused to t he a nter ior centra

intervertebral d isc centrum of vert e b r a

a nte r i o r

\ ,\\

IIII

II

I

posterior

o pisthocoelous vertebrae with the inter vertebral d i s c sf used to t he po s t er i or cent r a.

d i a gr a ms showing the f or m of the c e n t ra in Anura

89

F R 0 G SAN D T 0 A D S

tensor fa sciae l ata e

iliacus internus

coccygeo i l i a c u s

py r i form i s ---""--t:--,~ ~""

ta i l -------\

ca u da l i o pu b o i s c h i ot i b i a l i s(for tail-wagging)

cruralis

glutaeus

iliofibularis

+---- peroneus

plantaris longus

semimembranosus

gracilis minor gracilis major

s a rto riosemi t e nd i n o s u s

crural i s

t i b ia l is a nti c u s longus

pectineus

r ectusabdominis

pubis

f-------- t ail

gracilis minor

gr a c i l i s ma j o rventral

musculature of the thigh of As caphus

90

F R 0 G SAN D T 0 A D S

inguinal amplexus

axillary amplexus

the main forms of amplexus in Anura

91

F R 0 G 5 A NOT 0 A 0 5

xeno anuran(Pipida e, Rhinophryn ida e)

sco pta nuran(Microhylida c)

beak ---~'+t+1l1lI!"""'~

s pira c le \----4:.

be ak ----,l~~II:2'

dent icles--~~~~~~~~~~

l e mmanuran(L e i op elmatida e , Discoglossidae)

acosma nura n(Pelobat~dae, Buf onida e

Hyl ida e, Lept oda c t yl ida e ,Ranida e, Rha c opho r ida e)

d iagr ammatic ventral v i ews of a nuran t adpole t ypesba s ed on barbels, beaks, dent icle s a nd s pira c les

92

F R 0 G SA N D T 0 A D S

Family Leiop elma tidae

Ar cha eobatra chia in wh ich :-

• 1. The re a re t ypica l ly 9 pre sacral vertebrae i n

whi ch t he c e ntra a re ectochor da l i n

development a nd amphi c oelou s. ( 87 , 88 , 89 )

2 . The s acro-coccygea l articula t ion is

monocondyla r. ( 8 3)

3. The ster num i s not f orked po steriorly.

• 4 . A prepubi s is pre sent in the pelvic g i r d le .

In Ascaphus only the r e i s a lso a po stpubis . ( 94)

• 5. Tail-wa g g ing muscles (m. c a uda l i o pub o i s c h i o t i b i a l i s )

a re r etained i n the a du l t . (90)

• 6 . These s mal l , pr i mitive frogs are found i n

mountain s treams o f New Ze ala nd ( Leiopelma)

and the northwe s t U.S .A . (Asca phus) .

There are 4 spe cies in two genera .

Examples :- Leiop elma, Asca phus .

Hochstetter's frogLeiopelma

taile d frog - Ascaphus 0(with tail -like cloaca l

a p pe ndage for intromis sion)

93

F R 0 G SAN D T 0 A D S

~ ilium

--.i.~_--------prepubis"---,,.'}

\1:',~;;y-------- pubo-ischium

". .~

[:.1---------- po stpubis

ventral view of the pelvis of Ascaphus

ilium

~----- pubo-ischium

acetabulum -------+.........,;,::.

prepubis postpubis

lateral view of the pelvis of Ascaphus

94

F R 0 G SAN 0 T 0 A 0 S

IIIIIr..

:..:1; '­.o:: O(

I. .'::"1" .

I. ":' .,

~ I

. : :

,. ,

nI

95

F R 0 G SA N D T 0 A D S

Family Discoglo s sida e

Archaeobatrachia in which:-

1. There a re t y p i ca l l y 8 presacral vert ebrae in

which the c e ntra a re stego c ho r da l i n

development and opis thocoelous. ( 88 , 89 )

2 . The sa c ro- c o c cygea l articulation i s bicondylar

in Discoglos s us a n d Alytes and monocondylar

in Bombina and Barbourula. ( 8 3)

• 3 . Th e ster num i s f or ked poster iorly a nd ha s a

triradiate appe arance. (9 7 )

4. There a re no prepubic or postpubic e l e me nt s

i n the pelvic gir d l e . (94)

5. Ther e a re no t a i l-wa g g i ng muscles in the

adult. ( 90)

6. These Old World frogs are found in Europe and

North Africa and a l s o in China, Korea, t he

Philippine s a nd Borneo. Ther e are 12 s pe cies

i n 4 gener a .

Example s: - Di scoglossus, Alyt es, Bombina,Barbourula.

Alyte s ~ - midwifetoad ca r r y i ng e g g s

96

F R 0 G SAN D T 0 A D S

e p i cor aco i d

cla vicl e

s ter num

sca pu la

(epicor aco i d hornsdorsal t o sternum)

pect or al g i r d le o f~

o

d i s t r ibut i on of t he Di s c oglo s s ida e

97

F R 0 G SA N D T 0 A D S

Subo r de r Agl o s s a

Anur a i n which : -

Th ey

3 ·

• 4 ·

• 5.

• 6 .

• 7 .

• 8 .

• 1 . There i s no tongue .

• 2 . The pupil of the eye is rou n d .

The t r igemi na l a nd f a cia l ga ngl ia a re fus e d t o

f orm a single prooti c ganglion. (8 5)The pa r a s phen o i d l ack s a lae . ( 86)

Fre e r i b s are pr e s ent in t he j u ve ni le bu t fu s ed

to t he tra nsverse processes i n t he a d u lt .

The centra of t he vertebra e a re stegoc h or dal. ( 88)There a re f ree int ervert ebral d i scs. (89)

The epicoracoi ds of the p e c t ora l gird le ove rla p

narrowly ( Xenopus), s l ight ly ( Pi pa), o r no t at a l l

( Hyme noch i r us ) and the b a c k wa rdl y di r e cted e p i c ora c o i d

horns a re wi d e a nd s h or t o r a bsent (Hymenochirus). (1 01 )

. 9 . The s ca pula is overla i d a nter i o r ly by the c l avi c l e .(IO I)

10 . I n t he t h igh t he m. sartorius a n d t h e

m. semitendinosus a re no t separ ated , e x cept in

Xe nopu s where separation i s par t i a l. (90)

• 11 . Ampl exus is i ngu i na l. (9 1)

• 12 . The ta d poles h a ve n o d enticles or b e aks .

have paired s p i ra c les and barbels. (92)

SUBORDER

AGLOSSA------------ Pipi da e

African clawed toadXenopus

98

F R 0 G SA N D T 0 A D S

Family Pipidae

Agloss a in which:-

• 1. Thre e of the hind d i gits have claws, exc e pt

in som e species of Pipa where t her e is none.

The ph alang eal formula i s 2- 2- 3- 3, 2-2 -3- 4-3 . ( 100)

• 2. The sacral diapophyse s a r e broadly dila t ed .

The sacrum a nd coccyx are fused but Cretaceous

forms have monocondylar articula tion. (1 01 )

• 3 . The e u s ta c h ian tubes j oin and o pe n into t he

pharynx through a single median a pe r t u r e .

4. The se aquatic f r ogs a r e found in Af r i ca s ou t h

of t he Sahara ( Xeno pus , Hymenochirus ) and

tropical South America (Pipa). There a re

som e 20 or more specie s in 3 gene ra .

Example s:- Pipa, Xenopus, Hymenochirus.

o

Pipa ~ - Surinam toa dwith eggs on t he back

99

F R 0 G SAN D T 0 A D S

+------ we b

.---- c l a w

hind limb o f Xenopu s s howi ng claws a nd webbing

Xenopus , Hymen ochirus

distribution of t he Pipidae

10 0

F R 0 G SAN D T 0 A D S

epicoracoid scapulasuprascapula

~§0.~~I-----epicoracoid horndorsal to sternum

sternum

pectoral girdle of Xenopus with narrowly overlappingepicoracoids and the scapula overlaid by the clavicle

diapophysis ----isacrum

1------ urostyle (coccyx)

sacrum of Xeno us with broadly dilateddia 0 ses an USLon WLt e urost e cocc x

101

F R 0 G SAN 0 T 0 A 0 S

Suborder Rhinophrynoidei

Anura in which:-

• 1. The tongue is attached to the pharyngeal floor at

the posterior border and is protrusible .

• 2. The pupil of the eye is vertical.

• 3. The trigeminal and facial ganglia are fused to

form a single prootic ganglion . (85)

• 4. The para sphenoid lacks alae. (86)

5. There are no ribs.

• 6. The centra of the vertebrae are ectochordal. (88)

• 7. There are free intervertebral discs. (89)

• 8. The epicoracoids of the pectoral girdle overlap.

• 9 . The scapula is overlaid anteriorly by the clavicle.

10 . In the thigh the m. sartorius and the

m. semitendinosus are largely separate. (90)

• 11 . Amplexus is inguinal. (91)

• 12. The tadpoles have no denticles or beaks. They

have paired spiracles and barbels. (92, 104)

SUBORDER

RHINOPHRYNOIDEI ------ Rhinophrynidae

102

F R 0 G SAN D T 0 A D S

Family Rhinophrynidae

Rhinophrynoidei in which:-

• 1. There i s no sternum.

• 2 . The sac r a l diapophy s e s a r e broadly dilated

and the s acro-coc c yge al a r t icu lat ion is

bic ondylar. ( 83)

• 3 . The limbs a re specia lised for digging with

t he pre hallux covered with a large cor nified

spade a nd the s ingle ph alanx o f t he 1st toe

s ho ve l-sha pe d . The phalang e al formul a i s

2-2-3-3 , 1- 2- 3-4- 3. ( 10 4)

• 4. Th is burrowing, termi te-ea t i ng t oad i s f ound

in t he dry region be tween the Ri o Grande Valley

of Texa s a nd Costa Ri ca. It r eturns to water

only to breed . The re i s a s i ngle s pec i es .

Example : - Rhinophr ynu s dor s alis .

di s tribution o f t he Rhinophrynida e

Mexican burrowing t oa dRhinophrynus

10 3

F R 0 G SA N D T 0 A D S

head of the ta dpol e o f Rhino phrynus

tib iofibula

1s t digi t

prehallux

fused t ar sal s

s ke l e t on of t he right fo o t of Rhino hr nu sshowing t e eve opment 0 t e ~rst ~g~t or igging

104

2.

3 .

4 .5.

• 6 •

• 7 •

8.

9 .

• 10 •

• 11-

12 .

F R 0 G 5 A NO T 0 A 0 5

Suborder Pelobatoidei

Anura in which : -

1 . The tongue i s attached t o the pharyng eal floor

anter iorly a nd is capab le of pr otrus ion .

The pupil of the e ye i s vertical .

The trigeminal a nd f ac i al ga nglia a re fused to

form a singl e prootic ga ngl ion . ( 85 )The pa r asphenoid ha s lateral a l ae. ( 86)

There a re no ribs .

The c ent r a o f t he ver t ebr a e a re s tegochordal. ( 88)The r e are free intervertebral discs in the

juven i les a nd som e a dults . (89 )

The epi coracoids o f the pectoral g i r d le ove rlap

ventrally. Elongate, ba ckw ardly direct ed

e picor a c o i d h orns a re pre s ent .

The s c apula is not over laid a nterior l y by t he

c lavicle e x cept in Pelodyte s where there is

partial o verlay . (1 0 7)

In t he thigh the m. sa r tor i us a nd t he

m. semi t endinosus a re not s e para t ed . (90 )

Amplexus i s i nguinal . ( 91)

The t adpoles typic ally ha ve dent i cle s a nd beak s ,

a single s p i rac le on the l eft a nd no barbels. ( 9 2)

SUBORDER

PELOBATOIDEI -------- Pelob a t ida e

10 5

F R 0 G SAN D T 0 A D S

Family Pelobatidae

Pelobatoidei in which:-

• 1. The depressor mandibulae muscle is inserted

on the suprascapula . (117)

• 2. The sacral diapophyses are broadly dilated.

The sacro-coccygeal articulation is

monocondylar, or the sacrum and coccyx are

fused. (83, IOn

• 3. The hyolaryngeal apparatus is more or less

reduced .

4. The sternal apparatus is ossified in some

species .

5. These frogs are widely distributed in the

northern hemisphere and extend into south

east Asia and Indonesia.

species in 8 genera.

There are 54

Examples:- Pelobates, Scaphiopus, Pelodytes,Megophrys , Leptobrachium.

Iberian spadefoot toadPelobates

106

F R 0 G SAN D T 0 A D S

omosternum

scapula

epicoracoid

sternum

cleithrum

{epicoracoid hornsdorsal to sternum)

pectoral girdle of Scaphiopus

sacral diapophysis ____+ sacrum

I..11

urostyle (coccyx)11

11

fused sacrum and urostyle (coccyx) of Pelobates

107

F R 0 G S A N D T 0 A D S

)

.: :

10 8

IIII,t..

:.;,:.­. .:,"(

I·':.\'

Il)<ll'0. ~..,<ll.00

.-<Il)0.

Il).e..,"'"0c0

.~..,::l

.0....6 ....,

"'....'0

7 The New Frogs

The majority of frogs and toads (in terms of the

number of species) are generally considered advanced i n

c omparison with the archa ic forms covered in the previous

chapter. They are put together in the suborder

Neobatrachia in three superfamilies, Bufonoidea, Ranoidea

and Microhyloidea. Whereas the archaic anurans evidently

arose in the Mesozoic, the Neobatrachia appear to be mainly

Tertiary in origin . The bufonoid families, with the

exception of the hylids , are represented in the Palaeocene,

the ranoids in the Oligocene and the microhyloids in the

Miocene period . The Bufonoidea contains three families,

the Bufonidae which i s a l mo s t world-wide, the Leptodactylidae

mainly in the southern hemisphere and the Hylidae mainly in

the north. The Ranoidea also contains three families,

the Ranidae which is again world-wide , the Rhacophor idae

in Asia, Africa and Madagascar and the Sooglossidae found

only in the Seychelles . The Microhyloidea has a single

f amily, the Microhylidae, which is essentially pantropical.

The apparent relatively late origin of the

Neobatrachian families is at odds with their generally

wide distribution across the main continental masses.

Such distributions of animals that cross salt water with

difficulty would appear to be incompatible with a time of

origin when the separation of the continents was already

weIl advanced. Doubt, therefore, is raised a bou t both

the time of origin and the validity of the neobatrachian

families, which may contain relatively unrelated convergent

groups. At the moment, insufficient is known about these

anurans and their fossil history to resolve these questions.

109

T H E N E W F R 0 G S

The classification which is used here differs in some

respects from any so far proposed. This is due partly

to the arrangement of sets of matching characters into an

effective working pattern and partly to simplification of

the large number of families that have from time to time

been proposed , many of which are difficult to define.

In this guide most of the small often monotypic families

have been merged with larger f amilies a nd geographically

separated groups have been combined where their characters

appear to warrant it. Where amalgamations have been made

the t ype genera of the different groups are included in

the lists of examples following each family and some of

their special characters noted . A list of these type

genera and the famil ies in which they have been i nc l ude d

is given below. In a full classification most of these

groups would appear as subfamilies and in due course,

when more information is available, many may be g iven

family rank. The Sooglossidae with only two ge ne ra i s a

case in point where f amilial status now appear s to be fully

justified.

included type genera of

groups that may warrant

separate familial status

Leptodactylidae

Hylidae

Rhacophoridae

Microhylidae

Brachycephalus (Ea stern Bra zil)

Cyclorana (Australia)

Dendrobates (Central & S. America

Heleophryne (South Afri ca)

Myobatrachus (Australia)

Rhinoderma (Chile)

Centrolene (Central & S . America)

Pseudis (South Amer ica)

Hyperolius (Africa, Madaga scar& Seychelles)

Phrynomerus (Africa)

110

T H E N E W F R 0 G 5

Suborder Neobatrachia

Anura in which:-

• 1. The tongue is attached to the pharyngeal floor

anteriorly and is typically capable of protrusion.

• 2. The pupil of the eye is typically horizontal, but

there is a number of exceptions. (78)

3. The trigeminal and facial ganglia are fused to

form a single prootic ganglion . (85)

4. The para sphenoid has lateral alae. (86)

5. There are no ribs.

• 6. The centra of the vertebrae are holochordal. (88)

• 7. There are no free intervertebral dises . (89)

8 . The epicoracoids of the pectoral girdle may or may

not overlap ventrally and the form of the coracoid

horns differs in the various families. (113, 114, 128)

• 9 . The scapula is not overlaid anteriorly by the

clavicle, or the clavicle is absent (some

Microhylidae). (113, 128, 135)

• 10. In the thigh the m. sartorius and the

m. semitendinosus are fully separated, except in

Myobatrachus where separation is no~ quite complete.(90)

• 11. Amplexus is axillary except in Cyclorana,

Heleophryne, Myobatrachus and some Bufonidae. (91)

12. The tadpoles typically have denticles and beaks

(except in the Microhylidae), a single spiracle

and no barbels. (92)

SUBORDER

NEOBATRACHIA

SUPERFAMILY

Bufonoidea

---------+- Ranoidea

Microhyloidea

111

T H E N E W F R 0 G 5

Superfamily Bufonoidea

Neobatrachia in which:-

• 1 . The pectoral girdle is typically arciferal,

that is the epicoracoids overlap . (113, 114)

• 2 . The epicoracoid horns are weIl developed. (113, 114)

• 3. In the thigh the tendon of the m. semitendinosus

typically passes over (ventral to) the

gracilis museies except in some leptodactylids

where it passes between the m. gracilis major

and m. gracilis minor and in Myobatrachus

where it passes dorsal . (115)

4 . The tadpole typically has denticles and a

beak, a single spira cle on the left and no

bar-beLs , (92)

SUPERFAMILY

Bufonidae

Bufonoidea ----------+-Leptodactylidae

Hylidae

112

T H E N E W F R 0 G 5

ventral a s pec t

omo s t ernum

precoracoid br idg e( uniting e pi cor a c o i ds )

clavi cle ------\

e p i c ora c o i d ----t'----;;~----+'

coracoid------~

e p i coraco i d horns .....:=:....---~7.1~~ste rnum

me sosternum -----------\

x iph i s ternum ---------'"

prezonal region

zona l r e gion

postzonal region

(epicoracoid hornsdorsal t o sternum)

dia gram o f the ventral r egion of a n a r c i f e r a lpectoral girdle with short epicoracoid horns

113

T H E N E W F R 0 G S

ventral aspect

epicoracoids

c oracoid ---- ;:"",..

s ter na l blade----------~

epicoracoid horn ----------1

e pic o r a coi d museie ------/~~

mesoste rnum --------------------;

T .S.

s t erna l blade

epicoraco id horn

x iphisternum

diagram of the ve ntral region of an a r c i f e ra lpectoral girdle with long epicoracoid horns

114

T H E N E W F R 0 G S

semi tendinosus

grac i l is ma j orbufonoid c ondition

semitendino sus

t endon s

0~-\""----~ tendo ns

g r a c i l is maj or

r anoid condition

diagrammatic ve nt ra l vi ews s howi nethe musculatur e of t he left t high

115

T H E N E W F R 0 G S

Fa mi ly Buf o n i d a e

Bu f ono i d e a i n whi ch : -

• 1 . The depr e s s or ma nd ibulae museie is i n s erted

on t he otoccipita l a nd the s qua mosa l . ( 1 17)

• 2 . The pre zonal e lement of t he pectoral gir dle

is typica l ly a bsent . In At elopus t he

epic or a c o id horns are f use d mes i ally t hroughout

t hei r l e ngth a nd re place the ster num. (11 3 )

3 . The toes are we bbed, partly webbed, o r free.

The digit s d o no t e nd in dises. The ter mi na l

ph alang e s a re not c law-sha ped , but t ypically

s i mple a nd tapering. In som e genera they

are T-shaped.

4. There a re no accessor y phalange s . The

phalang eal f ormula i s 2-2 -3-3, 2-2 - 3-4-3.

• 5. No teeth a re pr e s ent.

• 6 . The sac ra l d i apophyse s are e xpanded. ( 8 3)

• 7 . In t he male t here i s t ypically an orga n of

Bidder whi ch i s an anterior development of

t he gona d . ( 118)

8 . Th e s e toads a re world-wide in di s tr ibution

e xcept fo r Madagascar , Ne w Gui ne a and Polyne sia.

There a re a bout 300 s pe c ies in 18 gener a .

Example s: - Buf o, Dendrophrynis cus, Ate l o pus ,Melanophryniscus, Or eophrynella,Nectophryne , Nectophrynoide s,

common African t oadBufo

116

T H E N E W F R 0 G S

s quamosa l

~t=======J----- quadrato jugal

mandible

otoccipita lregion

bsuprascapu la

d e pre s sormandibula e

quadra t e

Discoglossida e , Peloba t idae

depre s sormandibula e

otoccipita lregion

s quamosa l

fI#~=======::J----- qu adrato jugal

'X:~r==========::::::::;;2...._-mandible

quadrateLe pt o da ctyl ida e , Hyl ida eRan ida e , Rha c ophor ida e ,

Microh y lidae

suprasca pu la

~

depre s s o rma ndibula e

otoccipitalregion

~------------ s quamosa l

~~======::::::I----- qua dr- a t. oj uga I

""':1=---========----"--- mandible

Bu f on ida equa drate

dia g rams s howing t he i nsertion of the depre s s ormand ibula e museIe in a nu ran fami l ies

117

T H E N E W F R 0 G S

l iver l i ver

h ear t

\orga n of Bidder ------\,.

( ves t ig ia l ovary )

k idne y ---t---------II-

ves icu la r _ 1L__~====~~~~tsemi na lis

o

l .""".:::::;>--------t- f a t body

+----------,f-- test is

alla ntoicbla dder

c loaca

d i s s e c t i on of a male bufon id s h owi ng th e organ of Bidde r

118

E W F R 0 G ST H E N

II

IIII',

:.: 1; '­..:." ,'

I ,'::',: '' :

e

'"-e' ...C0

"":lI:C

V..c:..,""0

)

e0

' .....,:l

.0' ...s,...,

* fJl' ...-e

119

T H E N E W F R 0 G S

Family Leptodactylida e

Buf on o ide a i n whi ch :-

• 1. The depressor mandibulae museIe is inserted

on the s u pr asc a pu la , the otoccipital a nd the

s qua mo s a l. (117)

2 . Th e prezonal e lement of the pectoral g i r d l e

i s t ypically present , but not in Br achycephalus

where a l s o the epicoracoid horns are grea t l y

r educed a nd t here is no ste r num. In

Rhinoderma and Dendrobate s the pe ctoral g i rdl e

r e s embles the firmisternal t ype. ( 113, 122)

3 . Th e t oes ma y be webbed or fr ee . The digit s

may carry a dhesi ve dise s , but the te r mi na l

ph alange s a re not c l a w-sha pe d .

4. There a re no a c c e s sory pha l a nges , but the

numb er ma y be r educed . The phalange al

f o rmula is 2-2 - 3-3 (2-2-3-2 in Eup arkerella) ,

2-2-3-4-3·

• 5. Te eth are normally pre s ent i n the upper j aw,

but ab s ent in Br achyc ephalus a nd Rhinode rma.

• 6. Th e sa c ra l diapophyse s a re c ylindr i ca l or

only s l ightl y e x pa nde d. ( 83)

7. Ther e is no organ of Bidder .

8 . The s e frogs occur ma inly in t he southern

hemisphere in Australia , South Afr i c a, South

America a nd t he s ou t hern United Sta t es . There

are about 65 0 s pecies in s ome 45 or 50 genera.

Example s : Leptodactylus, Heleophryne,Pseudophryne, Cera tophrys , Hylode s,Te l matob ius, Limnod~na st e s,

Rheobatrachus , Brac ycephalus,Rhinoderma, Myobatra chus , Dendrobate s,Eu pa r kerel la , Cyclorana .Eleut herodact y l us .

120

T H E N E W F R 0 G S

Australian corroboree frogPseudophryne

Argentine horned fro gCeratophrys

South American arrow poison frogDendrobate,s

121

s c a pu l a

T H E N E W F R 0 G S

oss ifie de picoraco i d

cla v i cle

oss ifiedpr e cora coid cor aco i d

pectoral g i r d le of Brachycephalus

omo s t ernum

scapula

sternum

pectoral g irdle of Rhinoderma

122

epicoracoid horn

T H E N E W F R 0 G S

,~: I . : :

12 3

II

I

III',

:..:I ; :..:: ','

I·'::',:.

Q)C1l'0•.-1.-i

~ Q).c..,CH0

C0

•.-1..,:l.0

I ' .-I.....,.,•.-1'0

T H E N E W F R 0 G 5

Fa mily Hylidae

Bufonoidea in which:-

• 1. The depressor mandibulae muscle is inserted

on t he suprascapula, the otoccipital and the

squamo s al . (117 )

2 . The prezonal e lement of the pectoral g i r d le

is typically pres ent , e x c e pt in Centrolene. (113)• 3 . The t oes a re free or part ly webbed. The

digit s e nd in a dhesi ve dises, which may be

r educed, and the t ermina l phalanges are

typically claw- shaped (T-shaped in Centrolene

and Allophryne). (125)• 4. Accessory intercalary phalanges are present.

The phalangea l f or mu l a is 3-3- 4- 4, 3-3-4-5-4 . ( 125)• 5. Teeth a re typically present in the upper j aw .

6 . The sacra l diapophyses a r e typica lly e x pa nde d

except in Pseudis and Centrolene where they

are cylindrical . ( 83 )7. There i s no organ of Bidder .

8 . These a re mainly t ree - f r ogs found in North

and South Amer i ca , Eur a s i a , Australia a n d

New Gu i ne a.

i n 36 ge nera .

There a re a bout 600 spec i e s

Examples : - Hyla, Litori a, Acris, Pseudacris,Pseudis, Centrolene, Hemiphractus,Phyllomedusa, Allophryne .

Europe an green tree-frogHyla

124

T H E N E W F R 0 G S

disc -----f

terminal phalanx

left hand of~ showing discs and webbing

intercalaryphalanx

metatarsal

h

125

the

T H E N E W F R 0 G S

".- ,I ~.'. I

~:~..o·

a

0I

IIII v-, '"~

"Cl..........:I:

V..c:

J...,

""0c0........,:l.c.....t.....,

~UJ.....

"Cl

II

IIIr.

:.,; 1: '-':: '1 '

J, I. :'i I . : ~ ::'1'

12 6

T H E N E W F R 0 G S

Super family Ranoidea

Neo batra c h ia in which : -

• 1 . Th e pectoral g i r d l e i s typically f irmisternal,

t hat i s the epicoracoids unite at the

pre cora coid a nd cor aco i d borders and in most

cases a l o ng the e ntire me sial e dge s , except

in the So oglossidae. (12 8, 132)

• 2. Th ere a re no epi coracoid horns .

• 3. In the thigh t h e t endon o f the m. semitendinosus

passe s under (dorsal to) the gracilis mus cles . (115)

4. Th e tadpole typi cally has denticles and a

beak, a single spiracle o n the left and no

barbels . In Sooglossidae the young develop

dire ctly on t he back of the male . (92)

SUPERFAMILY

tRa n i d a e

Ranoide a----------------------- Sooglossidae

Rha cophoridae

127

T H E N E W F R 0 G S

ventral a s pect

o mosternum

pr e coracoid ----------4

cla vi cle ------\

e pi c oracoid s -----I---==--~.j

coracoid - - -/

me s o s t e rnum -----------t

xi phister num

pre z ona l r egion

zo na l r e g ion

pos t zona l r e g i o n

d i a gram of the ventra l r egi on o f a f irmi sterna lpe c tor al gir dle. Epicoraco id horns a re a bsent .

12 8

T H E N E W F R 0 G 5

Family Ranida e

Ranoide a i n which :-

• 1. The pect oral girdle i s complet e a nd t he

prezonal r e gion is ossi f ied . ( 128 )

2 . The t oes may be webbed or free, t he dig i t s

may o r may not e nd in dises, but t he ter mi na l

phalang e s a r e r arely claw-shaped .

3 . There a re no a cce s s ory intercalary ph alang e s.

The ph alange al f ormula i s 2- 2-3-3 , 2-2 -3- 4-3 .

4. Te e th may o r ma y not be pres ent in t he upper

jaw .

• S. The s acral dia pophy s e s are cylindrical. ( 8 3 )

6. The true fr o g s are found on a ll maj or l and

ma s s e s e xcept Antarctica. There are many

hundreds of species in a b out 36 ge nera .

Examples:- Rana, Astylosternus, Pe tropede t e s,Mantella, Ceratobatrachus.

common Europea n fr ogRana

Soiomon isiand sharp-nosed tro gCera tobatrachus

129

T H E N E W F R 0 G 5

)

!:,' . I

•

II

I

I,r.

:.: ,; .­. ,:,",'

,. .'., : :.\ '

I' ": ". ,

130

Q)

<tl'0•..1c<tl

0::

Q)..c:..,l

'"0c0

•..1...,:l.0•..1

~:.....,<JJ

•..1'0

T H E N E W F R 0 G 5

Family Soog l ossi dae

Ranoide a in which:-

• 1- In the pectoral g i r dl e the prezon al r e g i on

is car t i l agi nous a nd the epicora coid

cartilages o ver-Lap . ( 13 2)

2 . The t oe s have s hor t webs or a r e fre e . The

dig i ts do not e nd i n di s c s a nd the t erminal

phalanges are not c law-sha ped.

3 · The r e are no accessor y i nterca lar y phala nge s .

The ph alangeal f ormula i s 2-2 - 3-3 , 2-2 - 3- 4-3 .

4 . Teet h a re pr e s ent i n t he uppe r j aw.

• 5. The sacra l diapophy ses a re dila t ed . ( 83)

• 6 . These f rogs a re known only fr om the Se y chelle

I slands. There a re 3 s pecies i n 2 gene ra.

Example s : - Sooglossus, Ne s omantis .

Seyche.l.les f r o gSooglossus

131

T H E N E W F R 0 G S

omo ste rnum

ster nu m

pectoral g i r d le of Sooglossus

d i s t r ibution of t he Soogl ossidae

1 3 2

T H E N E W F R 0 G 5

Family Rhacophoridae

Ranoidea in which:-

• 1 . The pectoral girdle is complete and the

prezonal region is ossified. The xiphisternum

forms a bony style (Rhacophorus) or a broad

cartilaginous plate (Hyperolius) and the

base of the omosternum is generally forked.

• 2. The toes are webbed and may be used for

gliding. The digits end in discs and the

terminal phalanges are not claw-shaped.

• 3. Accessory intercalary phalanges are present.

The phalangeal formula is 3-3-4-4, 3-3-4-5-4 . (125)

4. Teeth are present in the upper jaw.

• 5. The sacral diapophyses are cylindrical. (83)

6. These are mainly tree-frogs found in Africa,

Madagascar, south east Asia, Japan and

Indonesia. There are about 89 species in

14 genera.

Examples:- Rhacophorus, Chiromantis,Hyperolius.

Javan flying frogRha~oph~ru~

133

T H E N E W F R 0 G 5

Afr ican arum fr ogHyperol ius

Q

d i str ibu t i on o f t he Rhacophor ida e

134

T H E N E W F R 0 G S

Superfamily Microhyloidea

Neobatrachia in which :-

• 1. The pectoral girdle is more o r l e ss reduced

but i s of the firmiste rnal t ype, that is t h e

epicoracoids (wh en present) unite a t t he

precoracoid a n d coracoid borders.

• 2. There a re no e p i c or a c o i d horns.

• 3. In t he thigh the tendon o f the m. s e mi t e n d i n o s u s

pa s ses under (dorsal t o ) the gracilis muscles. (115)

• 4. The tadpole ha s a single median spiracle,

but ha s no denticles , b e ak or barbels. ( 9 2)

SUPERFAMI LY

Mi c rohy la

Microhyloide a ---------- Microhylidae

---- s ca pu l a

c oracoid

ste r num

r edu c t i o n of t he pect oral g i r d le

135

T H E N E W F R 0 G S

Family Microhylidae

Microhyloidea in which:-

1. There is rarely prezonal (or sternal)

ossification in the pectoral girdle. (128)

2. The toes are normally free, the digits may

or may not end in dises, and the phalanges

are not claw-shaped.

3. There are typically no accessory intercalary

phalanges, the phalangeal formula being

2-2-3-3, 2-2-3 4-3, except in Phrynomerus

where it is 3-3-4-4, 3-3-4-5-4.

4. Teeth are absent from the upper jaw in the

majority of forms .

• 5. The sacral diapophyses are broadly dilated. (83)

• 6. Transverse glandular pharyngeal folds are

present.

7. These burrowing or tree-living frogs are

widespread in the Old and New World tropics

with extensions into the temperate regions

of North and South America, Africa and China.

There are many hundreas of species in about

56 genera.

Examples:- Microhyla, Breviceps, Phrynomerus,Dyscophus, Hoplophryne,Gastrophryne, Kaloula,Kalophrynus.

Mozambique rain frogBreviceps

136

T H E N E W F R 0 G S

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137

8 Glossary

Acosmanuran - the type of anuran tadpole in which the mouthhas a beak and denticles, but no barbels, and there isa single spiracle on the left side of the body. (page 92).

Ala - a wing-like projection from the para sphenoid bone.(page 86).

Allantoic bladder - the urinary bladder in amphibians arisingas a sac from the posterior region of the gut. (page 118).

Allantois - an embryonie membrane derived from the allantoicbladder and present in reptiles, birds and mammals.

Amnion - an embryonie membrane enclosing a fluid-fill ed cavity----CÖntaining and protecting the embryo in rept iles, birds

and mammals.

Amphicoelous - the condition in a vertebra where both endsof the centrum are concave. (page 89).

Amplexus - the sexual embrace of the female anuran by themale. (page 91).

Aortic arches - the arteries that pass from the ventral aortato supply the gills and thence unite dorsally to form thedorsal aortae. (pages 26, 27, 28).

Archipterygium - a leaf-shaped fin with a central skeletal axisand symmetrically arranged skeletal rods on each side .(page 6).

Arciferal - referring to an anuran pectoral girdle in which theepicoracoids overlap. (page 113).

Arcualia - the primitive cartilaginous elements from which thevertebra is constructed. (page 16).

Bidder's organ - a vestigial ovary found in male bufonidtoads. (page 118).

138

G LOS S A R Y

Cerebral hemispheres - the major lobes of the forebrain. (page 23

Cerebrum - see cerebra1 hemispheres.

Cervical - pertaining to the neck.

Chondrification - the formation of, or conversion into, cartilage

Chondrocranium - the cartilaginous cranium housing the brain.(page 85).

Chorion - the outer embryonic membrane in reptiles, birds andmammals.

Costal grooves - vertical grooves on the flanks of somesalamanders. (pages 51, 53).

Ectochordal - the condition in the anuran vertebra where thenotochordal sheath only is ossified. (page 88).

Epiphysis - a cap of bone that ossifies separately from themain bone.

Erythroeyte - a red blood cello

Firmisternal - referring to an anuran peetoral girdle inwhieh the epieoraeoids abut (do not overlap). (page 128).

Holaretie - the zoogeographie region designating the northernparts of the Old and the New World (Palaearetie + Nearetie).

Holoehordal - the condition in the anuran vertebra where boththe notochord and its sheath are ossified. (page 88).

Homodont - with all the teeth of similar type (not differentiatec

Hyolaryngeal apparatus - a complex of cartilages in the floorof the mouth formed from the hyoid and the larynx.

Intercalary phalanges - additional phalangeal elements presentin the hands and feet of some tree-frogs. (page 125).

Intromittent - referring to the male eopulatory organ.(pages 62, 93).

Laehrymal duet - the tear duet passing through the laehrymalbone from the orbit of the eye to the nasal eavity. (page

Laurasia - the northern part of Pangaea, the southern partbeing Gondwanaland.

Lemmanuran - the type of anuran tadpole in whieh the mouth hasa beak and dentieles, but no barbels, and there is asingle midventral spiraele. (page 92).

139

G LOS 5 A R Y

Metamorphosis - the transition from the larval state to theadult involving areorganisation of the body structure.

Monotypic - referring to a family in which there is asingle genus.

Neopallium - a new part of the cerebrum concerned with theassociation of impulses.

Notochord - a longitudinal elastic rod lying beneath thedorsal nerve cord in chordates. In adult vertebratesit is largely replaced by the vertebral column, but ispresent in the embryo. (page 88).

Opisthocoelous - the condition in a vertebra in which theposterior end of the centrum is concave and the anteriorend convex. (page 89).

Ossification - the formation of, or conversion into, bone .

Otic noteh - a notch in the posterior margin of the skull ofprimitive amphibians occupied by the tympanie membrane.It is bounded by the tabular above and the squamosalbelow. (page 11).

Otoccipital region - a posterior region of the amphibian skullformed by the fusion of the opisthotic and exoccipitalbones. (pages 47, 79, 80, 117).

Oviparous - producing eggs that develop and hatch outsidethe body of the female .

Ovoviviparous - producing yolky eggs that develop and hatchwithin the body of the female.

Paedogenesis - reproduction by young or larval animals.

Paedomorphic - characterised by a reproductively maturelarval state .

Pangaea - the single continent that fragmented to give thecontinental masses of the present.

Pantropical - found in all appropriate tropical areas.

Pentadactyl - having five digits on the foot. (page 81).

Pleurodont - with teeth set in a groove on the inner sideof the jaw bone.

Polyphyodont - having a set of teeth which are replacedmore than once.

140

G LOS S A R Y

Postzonal region - the posterior region of the sternal partof the anuran pectoral girdle. (pages 113, 128).

Prehallux - an accessory bony projection at the side of thefirst digit (hallux) of the hind limb . (page 104).

Prezonal region - the anterior r egion of the sternal part ofthe anuran pectoral g i r d l e . (pages 113, 128).

Procoelous - the condition in a vertebra in which the anteriorend of the centrum i s concave a nd the posterior e ndc on vex. (pa g e 89 ) .

Relict - referring to a persistent endemie populat ion or~ecies belonging to a van ishing or nearly e x t i nc t group.

Rudiment - a structure in which development has been a r r e s t e d----ar-;n early s tage .

Scoptanuran - the type of a nura n t adpol e in which the mouthhas no be ak, denticle s or barbels a nd there is a s i ngl emidventral s p i racle . (page 92) .

Seeondary palate - a bony shelf formed prineipally from themaxill a e whi ch s e pa rates the buccal a nd nasal ca v i ti e s.

Spermatophore - a s pec ia l capsule or packet contain ing s pe r mwhich i s e x t r uded by the male.

Stegochordal - the c ondition in the anuran vertebra wherethe upper half o f the not ochordal s hea t h only i s ossified.(pa g e 88 ) .

~ - a cate gory in classification such a s order or family.

Thermoregulation - the c on trol of the t emperature of the body.

Type genus - the genu s from which the f amily name is derived.

Vivipa rous - producing l iving young that have been nourishedwith in a nd by thc body of the f emale ( c ompare ovoviviparous) .

Walla ce' s Line - a line passing be twe en Bal i a nd Lombok,betwe en Celebe s a nd Borneo a nd running e as t o f t hePhil ippine s. The f auna s on either s i de of the lineare r e mar kab l y different.

Xenoanuran - the type o f a nura n t adpole in which the mouthha s barbels , but no beak or dentieles, a nd there i s apa ir of spiracles, on e on e a c h s i de of the body . (page 92).

Zonal reg i o n - the central r e gion of the sternal part of theanuran pe ctoral g i r dle . (pages 11 3, 128).

141

List of generic names quoted

77, 120

93; 9510686 ; 120120

Eleutherodactylus

Eodiscoglossus 7269

Eurycea

Epicrinops

Euparkerella 12053, 54·

13668

68

Hymenochirus 98, 99, 100Hynobius 30, 40·Hyperolius 110, 133, 134·Ichthyophis 60, 63; 64; 69; 70·Kalophrynus 136Kaloula 136Leiopelma 84,Leptobrachium

Leptodactylus

Limnodynastes

Litoria 124

Lysorophus 60Mantella 129Megalocephalus 21; 22·Megophrys 106Melanophryniscus 116

Microhyla 135; 136

Gymnophi s

Heleophryne 110 , 111 , 120, 123Hemiphractus 124

Hoplophryne 136Hydromantes 53Hyla 124; 125·Hylodes 120

Gastrophryne

Geotrypetes

Acris 124Allophryne 124Alytes 96~ 97·

29 30 34·, 50, 51·,Ambys toma , ,52"

Amph i u ma 46~ 47·Andr ias 36, 37 ·As caphus 87 ~ 90; 9 3; 94; 95Astylos t ernus 129Atelopu s 116Barbourula 96Batrachuperus 40, 41·Bombina 86 ; 96Br achyc ephalus 110, 120, 122·Br eviceps 136·Bufo 79; 80; 81; 82; 116; 119Ca e cilia 6 2~ 68·Caudacaecilia 69Ce n t r o l e n e 110 , 124Ceratobatrachus 129·Ceratophrys 120, 121·

Chiromantis 133Chthonerpet on 66, 67·

Cryptobranchus 34; 36; 39·Cyclorana 110, 111, 120, 123Dendrobates 110, 120, 121·

Dendrophryniscus 116De smognathus 53, 55·Dicamptodon 50Discoglossus 84, 96Dyscophus 136

142

GEN E R I C N A M E S

40

133 ·

120

Mi ob a t r a chu s 72, 73 ·

Molge 4 4

Montsechobatrachus 72

Myob a t r a chu s 110 , 111, 112 ,120 , 12 3

Nectocaecilia 66

Nectophryne 116

Nectophrynoides 77 , 116

Necturus 30, 48, 49 ·

Neoceratodus 5 , 6 ·

Nesomantis 13 1

Notobatrachus 72, 73 ·

Onycho dactylus 40

Oreophrynella 116

Oscaeci lia 68

Osteolepis 11

Palaeo~rinus 11"

Pe lobates 106 ; 107 ·

Pelodytes 105, 106

Pe t r ope de t e s 129

Phrynomerus 110, 136

Pseudacris 12 4

Ps e ud i s 110 , 12 4

Pseudobranchus 57

Ps e ud o phr yn e 120, 12 1·

~ 78 ; 129·

Ra nodon 35,

Rhacophorus

Rheobatrachus

Rhinatrema 69

Rhinoderma 110 , 120, 122 ·

Rhi nophrynus 76, 86; 103 ; 10 4 ·

Rhyacosiredon 50

Rhyacotriton 50

Salamandra 43; 44

Scaphiopus 106, 107 ·

ScolecomorEhus 62 ; 7 1

Siren 56 ; 57, 58·

Sooglossus 131; 132·

Te lmatobius 120

Triadoba trachus 72, 73·

Triturus 44·Ph yl lomedusa 124 Typh lomolge 53Pi pa 86 ; 98, 99; 100 Typ h lonectes 60, 66Plethodon 53; 55 · Tylototriton 33 ; 34 : 44Pot omo t y ph l u s 66 Vieraella 72Pr ot e us 29 , 30, 48 : 49 Xenopus 98 ; 99, 100 ; 10 1·

14 3

List of common names quoted

Australian lungfish(Neoceratodus) 5

Axolotl (Ambystoma) 30; 50

Caecilians 18, 59, 60

Congo eel (Amphiuma) 42, 46·

Fro g s 18, 72 , 74, 75 , 109

Afr ican arum (Hyperol ius) 134·

Ar gent ine horned(Ceratophrys) 121·

Australian corrobore e(Pseudophryne) 121·

common European (Rana) 129·

Hochstet t er' s (Leiopelma) 93·

Javan fly ing (Rha cophorus)133·

Mozambique r a in (Breviceps)136·

Seychelles (Sooglossus) 131·

Soloman I sland s ha r p - no sed(Ceratoba trachus) 129·

South Amer i can arrow poison(Dendrobate s) 121·

t ailed (A scaphus) 93·

tre e 124; 133 , 13 6

true 129

Hellbender (Cryptobranchus) 35,36·

144

Mud-puppy (Necturus) 42, 48

Newts 18, 29, 42, 44

marbled (Triturus) 44·

Olm 42, 48

European (Proteus) 48·

Salamanders 18, 29, 42, 44

Asiatic land 35, 40

giant (Andrias) 35, 36 , 37·

lungless 42, 53

marbled (Ambystoma) 51·

mole (Ambystoma) 42, 50, 51·

red-backed (Plethodon) 53·

Siberian (Hynobius) 40·

Siren (Siren) 56; 57

Toads 18, 72 , 74, 109, 116

African c l a wed (Xenopus) 98·

common African (Bufo) 116·

Iberian spadefoot (Pelobates)106·

Mexican burrowing(Rhinophrynus) 103·

midwife (Alytes) 96·

Surinam (Pipa) 99·

Tree-frogs 124; 133, 136

Europe an green (Hyla) 124·