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BULLETIN OFTHE AMEICN MUSEUM :OF NATURAHITR VOLUME 13 ARTICLEJ1NWYR:16

HIGHER TAXONOMIC CATEGORIES OF GEKKONID LIZARDS AND THEIR EVOLUTION

ARNOLD G. KLUGE Assistant Professor of Zoology The University of Michigan Ann Arbor, Michigan

BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY VOLUME 135 : ARTICLE 1 NEW YORK 1967 BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY Volume 135, article 1, pages 1-60, textfigures 1-8, plates 1-5, tables 1-3, maps 1, 2 Issued January 20, 1967 Price: $2.50 a copy CONTENTS

INTRODUCTION...... 5

Acknowledgments...... 8

Methods and Materials ...... 9

THE FAMILY GEKKONIDAE ...... 10

Family Gekkonidae ...... 10

Characterization...... 10

Range...... 12

Fossil History ...... 12

THE SUBFAMILIAL CLASSIFICATION...... 14

Shape of the Pupil as a Systematic Character ...... 14

Analysis of Characters...... 14

True Eyelids or Spectacle ...... 15

Premaxillary Bone ...... 15

Endolymphatic Apparatus ...... 16

Preanal Organs and Escutcheon Scales...... 17

Ability to Vocalize ...... 18

Number of Eggs Laid ...... 19

Supratemporal Bone ...... 19

Number of Scleral Ossicles ...... 20

Cloacal Sacs and Bones ...... 24

Angular Bone ...... 33

Splenial Bone ...... 33

Frontal Bone ...... 33

Nasal Bones ...... 34

Parietal Bone ...... 35

Amphicoelous or Procoelous Presacral Vertebrae...... 35

Hyoid Arch ...... 36

Second Visceral Arch ...... 38

Squamosal Bone ...... 38

Evolution of the Subfamilies ...... 39

Subfamily Eublepharinae ...... 41

Subfamily Diplodactylinae...... 41

Subfamily Gekkoninae...... 42

Subfamily Sphaerodactylinae...... 42

...... Zoogeographical History of the Subfamilies ...... 44

SUMMARY...... 51

APPENDIX 1 ...... 53

LITERATURE CITED ...... 55

3

INTRODUCTION

THE FAMILY GEKKONIDAE comprises a well- (1964). The tails of gekkonid lizards, which circumscribed, natural group of lizards, con- are almost always autotomic, vary from be- sisting of 82 genera and more than 650 species ing long and attenuate or depressed (leaflike) and an additional 175 subspecies. The family to being extremely short and bulbous. Some is widely distributed between latitude 500 N. tails have a subepidermal lymphatic ejecting and latitude 500 S. (map 1). Gekkos are found mechanism (Bustard, 1964), and a few others on all major land masses and have been suc- are prehensile. The distal under surface of the cessful in invading most oceanic islands. They tail, when prehensile, is in many cases covered have become adapted to the rainless northern with lamellae, similar in structure to those of coast of Chile and to the extreme monsoon the digits. The tail apparently serves as a region of eastern India. food reservoir in those cases in which it be- Within the family Gekkonidae there is a comes extremely swollen with fatty tissue. vast array of structural and biological diver- Most gekkos vocalize. The sounds pro- sity. Adults vary from less than 40 mm. to duced are extremely variable in pitch, dura- considerably more than 350 mm. in total tion, and frequency. The call may vary from length. Usually the body is flattened, but isolated clicks to a trilled series of chirps, some species are compressed and approach deep-throated barks, or quacking ducklike the habitus of true chameleons. A few forms sounds. Some species are reported to call in have extensive skin folds on the body and large choruses with an "almost deafening" tail which, when extended, enable the animal volume (Loveridge, 1947; see also Brain, to glide from tree to tree; some species have 1962a). There is evidence in a few cases that large dorsal crests on the body and tail. The the calls of closely related species are different scalation may be either homogeneous or het- (Haacke, 1964; Werner, 1965). The vocal- erogeneous and consists of minute granules, izations appear to aid in the establishing of tubercles, or large platelike scales that range territories (Mertens, 1955; Werner, 1965), from being juxtaposed to being imbricate. and it has been suggested that they may also Scale sensory organs are common. Most gek- discourage predators. In the genus Tera- kos have a thin, delicate skin which is loosely toscincus, each species rubs together its attached by connective tissue to the under- greatly enlarged supracaudal plates to pro- lying muscles or bone. Some species have very duce a shrill, cricket-like noise (Gadow, 1901; thick skins supplied with osteoderms which Mertens, 1946). may or may not be fused to part or to all of In the few species of gekkos that have the skull. been studied, the reproductive behavior is Gekkonid lizards are well known for their complex. It may involve various precopu- extremely variable digits and tails and their latory movements of the body, head, and ability to vocalize. The digits are long and tail, vocalizations, the contact of preanal slender, angulate or straight to extremely pores and cloacal sacs, and the use of cloacal dilated. The hands and feet may be fully bones to enlarge the cloacal aperature which webbed, and the claws may be retractable in- facilitates the introduction of one of the to specialized sheaths. The fifth digit, and hemipenes (Greenberg, 1943). Some species claws numbering from one to four, may be exhibit no definite seasonal reproductive lost. The dilated areas or "pads" consist of cycle, and mating may take place throughout narrow to wide, divided or undivided lamel- the year, but in other forms breeding appears lae, each of which bears numerous micro- to be cyclic and restricted to a very short scopic, hooklike projections that appear to period during the year. There is evidence that facilitate movement in the arboreal environ- some females can retain sperm for a consid- ment by catching on surface irregularities; erable period (Church, 1962; Quesnel, 1957). also, the existence of a climbing mechanism In others, delayed oviposition occurs until dependent on an electrostatic charge has re- embryonic development is well advanc- cently been repostulated by Maderson ed. Most species of gekkos lay one or 5 0

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6 1967 KLUGE: GEKKONID LIZARDS 7 two uniformly white, round to oval, calcar- 3 feet in length. The burrow may be simple eous-shelled eggs. A few species bear living in structure or consist of a major tunnel with young, in which case a shell-secreting area in many blind side branches which approach the the oviducts is absent (McCann, 1955); in surface of the ground (Haacke, 1964). Most these species the newborn young are from gekkos are nocturnal, but some species one-third to one-half of the size of the parent. actively feed and bask in direct sunlight; The eggshell is soft, pliable, and moist when many are active during the day but do not first laid but hardens and drys after a short move beyond shade. Some nocturnal species exposure to air. Some eggs have an adhesive are occasionally, but apparently not fortu- glutinous covering when laid which enables itously, active in the sunlight (Brattstrom, them to adhere to one another and to vertical 1965; Werner, 1965). Peritoneal and cranial surfaces. A fertile egg may measure as much pigmentation has been noted in a few sup- as 17 mm. in length and 21 mm. in diameter. posedly nocturnal species. The body temper- Eggs of some species can withstand long atures of active nocturnal gekkos have been periods of exposure to sea water (11 days and reported from 10.20 C. to as high as 34.00 C. probably longer) and still remain viable (mean ranges, 15.2° C. to 27.60 C.) and for a (Brown and Alcala, 1957). The incubation diurnal species from 28.50 C. to 36.50 C. period of the eggs varies from 40 to longer (mean, 32.70 C.). The critical thermal max- than 70 days (122 days has been reported; imum for nocturnal animals has been shown Kopstein, 1938), and, upon hatching, the to range from 41.6° C. to 45.5° C. and for a young gekko invariably sheds its skin and diurnal species from 43.5° C. to 44.4° C. Noc- often eats it. Communal egg laying appears turnal gekkos attempt to reduce their body to be common; 186 eggs were collected from temperatures by panting earlier than their one window-shutter (Mell, 1922). Gekkos diurnal counterparts (panting starts in noc- apparently do not guard their eggs nor do turnal species at temperatures from 31.00 C. they exhibit any paternal care of the young. to 39.70 C. and in a diurnal species from Sexual maturity may be attained within 30 to 41.40 C. to 42.50 C.). Gekkos also com- 40 days (Cagle, 1946). Adults shed their skin monly respond to excessive heat by attempt- in flakes or very large pieces at least twice a ing to burrow into the ground or by standing year. with their legs straightened so that the body Gekkonid lizards may be solitary or gre- and tail are elevated above the substrate garious (20 of one form were collected under a (Brain, 1962b; Brattstrom, 1965; Stebbins, small strip of bark, and 31 of another inside a 1961). basaltic boulder; Oliver and Shaw, 1953, and The margins of the iris are extremely mo- Hoofien, 1962), and a few species are com- bile, and apparently this mobility has en- monly found in association with man. Gekkos abled members of the family to adapt to a are terrestrial, arboreal, or both, and some wide range of light intensities (Werner, 1965). are known to enter fresh water (Annandale, The pupil area can be changed as much as 1905); a few are cavernicolous (Inger and 300-fold (Denton, 1956); this degree of mo- King, 1961; Kluge, 1963). One species has an bility enables the animal to shield the pure altitudinal distribution from near sea level rod retina from saturating light. The two (500 meters) to 4000 meters (Bons, 1959). irises are completely independent of each Gekkonids spend their inactive periods under other and are under voluntary control (Den- rocks, bark, natural debris, or refuse of hu- ton, 1956). "Eyeshine" has been detected in man habitation. Some species of gekkos some nocturnal gekkos. In most forms the occupy vacated burrows of other organisms eyes are protected by a spectacle (brille) in- such as spiders, lizards, and mammals, stead of movable (true) eyelids. It is common whereas others excavate their own tunnels for gekkos to lick the spectacle with their which vary from being horizontal to being tongues and apparently clean its surface in nearly vertical relative to the surface of the absence of movable eyelids which normally ground. Self-excavated burrows have been perform this function (Bustard, 1963; Werner found to extend more than 16 inches below 1965). the surface of the ground and may reach 21 to Gekkonids are usually various shades of 8 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 gray or brown. These colors seem to be of genera within the family: the Euble- associated with their predominantly noc- pharinae, Diplodactylinae, Gekkoninae, and turnal habits. Diurnal species may be yellow, Sphaerodactylinae. The number of assem- red, blue, or bright green. Intrasexual and blages recognized, and their names, coin- intersexual dichromatism is moderately rare. cide with those of previous studies. It is im- Metachrosis is pronounced in a few diurnal portant to note, however, that the subfamilial forms. The oral cavity and tongue may be names Gekkoninae and Diplodactylinae are white, pink, blue, or black. retained, even though they differ markedly Most gekkos feed on arthropods (primar- from those of Underwood (1954) in their ge- ily insects), but the larger species eat other neric composition. Also, the eublepharine and lizards and even small birds and mammals, sphaerodactyline groups are considered to be including bats. Some species have been re- of a taxonomic rank equal to that of the ported to eat snails, tidal crustaceans, and Gekkoninae and the Diplodactylinae, in con- the fruits, bark exudate, and flowers of trast to Underwood's arrangement in which plants (McCann, 1955). Common predators they are treated as families. Finally, a general on gekkos include mammals, birds, snakes, evolutionary and zoogeographical history of lizards, and a wide variety of arthropods the subfamilies is postulated. For simplicity's (spiders and centipeds). The Gekkonidae sake, particularly in the section on the anal- exhibit diploid chromosome numbers of 32 to ysis of characters, I have used the names of 46; metacentric chromosomes (4) have been the subfamilies that are defined later in the described in one species (Goin and Goin study rather than repeat the numerous ge- 1962; Werner, 1956). neric names for each character-state under All the major families of lizards, with the discussion. exception of the Gekkonidae (and possibly the Scincidae), have proved to be stable ACKNOWLEDGMENTS taxonomic units since the nineteenth century During the last six years many people and (Underwood, 1954). Efforts to classify gek- institutions throughout the world have con- kos largely on the basis of the form of the tributed valuable material, information, and digit (Boulenger, 1885) and the shape of the advice to the present study. The successful pupil (Underwood, 1954) have proved to be completion of this research could not have inadequate for delimiting natural assemblages been realized without their aid. It is with of genera (Stephenson, 1960; Kluge, 1964). pleasure that I thank Mr. Kraig K. Adler, The present research is a further attempt to Mr. Jerry A. Anderson, Mr. Richard E. Bar- define the major evolutionary lines within the wick, Dr. Charles M. Bogert, Mr. Stanley family Gekkonidae, but on the basis of mul- Breeden, Mr. John H. Calaby, Mr. Harold G. tiple external and internal characters. The Cogger, Mr. James D. Fawcett, Dr. Vivian F. degree of relationship between the lines and FitzSimons, Mr. Dale L. Hoyt, Dr. Robert the nature, direction, and amount of evolu- F. Inger, Dr. A. K. Lee, Mr. Hymen Marx, tionary change that each assemblage has Dr. Sherman A. Minton, Jr., Mr. F. J. undergone are also considered. Mitchell, Dr. Georges Pasteur, Dr. Glen M. The affinities of the Gekkonidae are first Storr, Dr. Charles F. Walker, and Dr. briefly discussed and then followed by a Richard G. Zweifel. I wish to express my detailed characterization of the family. The gratitude to Dr. A. R. Main of the Depart- fossil history of the family and related groups ment of Zoology, University of Western is reviewed in an effort to determine the age Australia, who was largely responsible for the of the assemblage and the relative primi- success of my study program in Australia tiveness of the characters used in the study. from July, 1961, to September, 1962, where The characters that appear to be significant much of the present research was carried out. in a definition of the major evolutionary I wish to thank Dr. Garth L. Underwood of lines within the Gekkonidae are then dis- the Faculty of Agriculture, University of the cussed in detail preceding the section on West Indies, Trinidad, for introducing me to coding, weighting, and character associa- the major classification of gekkos and offer- tions. From an analysis of the character ing many valuable suggestions. I am greatly associations I have defined four major groups indebted to Dr. Ernest E. Williams of the 1967 KLUGE: GEKKONID LIZARDS 9 Museum of Comparative Zoology, Harvard every genus and species from which infor- University, for his counseling, suggestions, mation was taken. As a matter of conve- and criticisms during the course of this study. nience I have selected the recent check list Dr. Williams made available to me many of the gekkos of the world by Wermuth critical species of gekkonids; the completeness (1965) as the authority on recognized genera of the generic survey is due principally to and species and the spellings of scientific his generosity. Dr. Jay M. Savage of the names. Only in the cases of Alsophylax Department of Biology, University of tuberculatus (= Bunopus tuberculatus), Gek- Southern California, is responsible for my ko listeri (= Lepidodactylus listeri), Gekko interest in the evolution and zoogeography oorti (=Lepidodactylus oorti), Gekko pumilus of gekkonid lizards. Under his guidance all (= Lepidodactylus pumilus), Gekko smarag- my graduate studies were carried out, and to dinus (=Pseudogekko smaragdinus), Gymno- him I extend my sincere appreciation. dactylus antillensis (= Gonatodes antillen- The present study was aided in part by the sis), Pseudogekko shebae (= Lepidodactylus National Institutes of Health, Institute of shebae), and Tropiocolotes helenae (= Mic- Arthritis and Metabolic Diseases, Grant A- rogecko helenae) have I used new combina- 3549. I thank the Department of State, Office tions without here giving justification. My of Educational Exchange, Washington, D. C., evidence supporting these changes is in prep- which made possible the granting of a Ful- aration. Also, I have recognized the follow- bright Scholarship to Australia and the Intra- ing: Aeluroscalabotes dorsalis as a species dis- Australian Travel Award from July, 1961, tinct from A. felinus (Kluge, in preparation); to September, 1962. Sigma Xi and R.E.S.A. Coleonyx brevis as a species distinct from C. Societies provided financial assistance during variegatus (fide Kluge, 1962); Cyrtodactylus the summer of 1963, so that I was able to and Gymnodactylus as distinct genera (fide study gekkonid material in the collections of Underwood, 1954); Diplodactylus and Lucas- museums in the United States. ium (Lucasius) as congeneric (fide Kluge, MS; Gehyra punctata as a species distinct METHODS AND MATERIALS from G. variegata (Glen M. Storr, personal In the present study I have examined the communication); Gymnodactylus milii and G. soft parts and skeleton of examples of 74 sphyrurus (= Phyllurus milii and P. sphyru- genera and 195 species and subspecies, rep- rus; fide Kluge, MS); Hemidactylus albofascia- resented by 548 whole specimens (see Appen- tus (= Teratolepis albofasciata; Jerry A. An- dix 1). An additional eight genera and 88 derson, personal communication); Phyllo- species were examined to obtain further in- dactylus guentheri as a species distinct from P. formation on scleral ossicle numbers and the marmoratus (James R. Dixon, personal com- condition of the nasal and parietal bones munication); Ptenopus garrulus maculatus (those listed in table 1 but not in Appendix 1). =P. garrulus;fide Brain, 1962a). Justification The specimens used in the osteological anal- for the many new combinations in Diplo- yses were prepared either by the clearing and dactylus can be found in Kluge (MS). staining (Alizarin red-S) technique outlined Scleral ossicle counts always indicate the by Davis and Gore (1947) or by the use of number of elements enci;rcling a single eyeball dermestid beetles. Additional skeletal infor- unless otherwise stated. In the data section mation was obtained from stereoscopic radio- on the number of scleral ossicles (pp. 20-31) graphs with the use of low- and high-voltage the average deviations of the mean ossicle X rays. All observations were made through counts of the genera were calculated from the low-power objectives of a stereoscopic dis- following formula: secting microscope, and detailed dissection of the soft anatomy and disarticulation of the 1 -X2 skeleton were carried out when necessary. n Osteological terminology follows Romer (1956) and Kluge (1962) unless otherwise in which x1 is the mean of the species in the stated. subfamily, x2 is the mean of the species in It has not been possible within the limits the genus, and n is the number of genera in of this study to determine the validity of the subfamily. THE FAMILY GEKKONIDAE THE GEKKONIDAE AND THE limbless, snake- for certain characters in Drosophila, and, like lizards of the family Pygopodidae (and, as he stated (p. 225), "In the genetic sense, tentatively, the Dibamidae and the Anely- the genotypes responsible for the character tropsidae) have been grouped together in states will be completely homologous, if not the infraorder Gekkota by Underwood virtually identical; but the character will (1957). Underwood has discussed in detail appear many times independently, which is to more than 40 morphological similarities be- say that it can occur independently in spe- tween the gekkonids and the relatively more cies derived from species that did not show highly specialized pygopodids. The numerous the characteristic, even though the genotype similarities strongly suggest a close relation- for the character was potential within their ship between the two groups and support gene pools." their placement together in the Gekkota. The absence of a supratemporal arch read- Despite the obvious affinity between the two ily distinguishes the Gekkonidae from all families, Camp (1923) and Underwood have other lizards of the suborder Ascalabota, pointed out that the absence of the M. rectus which includes the Ardeosauridae, Xantusi- superficialis in gekkos and its presence in py- idae, Iguanidae, Agamidae, and Chamaeleon- gopods precludes the possibility that the lat- tidae. The living Gekkota have retained some ter group of lizards were derived directly from primitive morphological features (Camp, a gekko stock. The importance of this muscle 1923) and, with the infraorder Iguania (which in the determination of saurian relationships includes the Iguanidae and Agamidae), are may be somewhat lessened if not totally dis- considered by most students of reptilian evo- counted, however, when its developmental lution to be the oldest surviving lizards. The plasticity is considered (Maurer, 1896, 1898; gekkonid stock appears to have differenti- Camp, 1923). Also, it is possible that, if the ated very early in saurian evolution; it has genotype for the M. rectus superficialis was retained only a relatively few generalized present in a heterozygous (polyalleic) form features and in the main is very specialized in most (maybe all) of the main lines of (Romer, 1956). squamate evolution, segregation within the It is necessary to describe the family descendent gene pools could account for the Gekkonidae in detail in this section, so that peculiar distribution of the muscle among its relationships to the other members of the modern groups (e.g., in the Ascalabota it is Gekkota can be more accurately interpreted present in the Pygopodidae, Dibamidae, in future studies. This characterization rep- Xantusiidae, and some Agamidae- Uromas- resents a summary of the information pre- tix, Physignathus, and Liolepis; Camp, 1923; sented by Underwood (1954, 1957) and Underwood, 1957, p. 240). This reasoning Romer (1956) and additional data accumu- follows that given by Throckmorton (1965) lated by me.

FAMILY GEKKONIDAE CHARACTERIZATION: Skull generally de- a low, very thin, interorbital septum) sur- pressed and broad, dermal bones usually very rounding olfactory lobes; supraorbital rarely thin, rarely sculptured; osteoderms occa- present; postfrontal present; postorbital ab- sionally present; postorbital and supratem- sent (possibly fused to postfrontal); parietal poral arches absent; premaxilla developing foramen absent; parietals greatly expanded, from one or two centers of ossification, paired generally paired; supratemporal rarely pres- condition persisting in some adults; nasals ent; squamosal occasionally absent; quad- generally paired; frontal rarely paired in rate relatively large, complex, generally ar- adults; descending processes of frontal (which ticulating with opisthotic, rarely with prootic; meet and fuse ventrally and are underlain by lacrimal absent (?); jugal almost invariably 10 1967 KLUGE: GEKKONID LIZARDS 11 present, reduced, in many cases rudimentary; prehensile; caudal vertebrae extremely vari- vomers broad, platelike, generally convex able in number; generally four to six non- below, fused or paired, set at higher level than autotomic postsacral vertebrae immediately posterior palatal elements and only barely posterior to sacrum; septa, except in touching border of palatines; paleochoanate Nephrurus asper, present in caudal centra, palate-vomer and maxilla not touching or septa concentrated regionally or found overlapping; pterygoid touching maxilla or throughout; postparapophyseal mode of au- nearly so; interpterygoid vacuity broad, ex- totomy; chevrons free, intercentral. Limbs tending forward to vomers; large bony shelf well developed; generally five digits; fifth extending between basitrabecular process metatarsal short and broad, receiving spinous and prootic; pterygoid flange well developed; projection of metatarsal IV; intermedium ectopterygoid small, rodlike, projecting dor- absent; paraphalangeal elements present in soposteriad; parasphenoid rostrum very small many species with dilated digits; claws rarely or absent; anterolateral wall of cranial vault absent. Cloacal bones rarely absent, when formed by prootic; prootic not bordering present, one or two pairs. parietal or does so but slightly; paroccipital Body almost invariably flattened; skin process of opisthotic almost invariably pres- usually soft, rarely adherent to skull; head ent. Stapes generally perforate; internal scalation asymmetrical. Choanae without process of extracolumella present or absent. separate opening for well-developed vomer- Scleral ossicles 12 to 40. Angular generally onasal organ, lacrimal duct opening into absent; surangular almost invariably fused canal of vomeronasal organ, and choanal with articular and prearticular; splenial folds leading to same canal. Tongue fleshy, rarely lost, when present confined to inner only slightly extensible, covered with small middle section of jaw; Meckelian canal imbricate protuberances distally and large completely surrounded by dentary. Teeth villose papillae proximally, tip uncleft or pleurodont, homodont, typically small, nu- slightly cleft. Eyes usually extremely large; merous, cylindrical, and pointed; teeth spectacle (brille) generally present, movable confined to marginal series on dentary, (true) eyelids almost invariably absent; premaxilla, and maxilla, absent from palatine mobile vertical iris generally present; visual and pterygoid; two egg teeth present in cells without oil droplets; single visual oviparous species. Second visceral arch cells (type A) and standard saurian double discontinuous, except in Coleonyx; second cells (type B) alternating in horizontal ceratobranchial completely absent or moder- rows; peculiar double elements (type C) ately long; second epibranchial almost in- also present; fovea present or absent. Tec- variably in contact with skull; hyoid arch torial membrane originating on large mar- generally continuous; hyoid cornu rarely ab- ginal lip of cochlea. Scales of lips bearing sent; inner proximal ceratohyal projection scale (lenticular) organs. Endolymphatic present or absent. Clavicles generally ex- sac usually protruding from cranial vault panded, perforate; interclavicle extremely between parietal and opisthotic elements, variable in shape; two well-developed scapu- or through vagus foramen; sac greatly locoracoid fenestrae, rarely emarginate; ster- enlarged and calcified in neck region between nal fontanel present in some cases; one to skin and superficial musculature. Proximal three sternal ribs. Vertebrae short, ventrally belly of M. biceps brachii simple. Preanal nearly square in outline, centrum cylindrical, pores generally present in males, rarely in slightly constricted in middle; procoelous or females. Hemipenis forked, cuplike. Post- amphicoelous, some intermediate; procoelous cloacal sacs generally present. Digits fre- condyle narrower than body of centrum; gen- quently undilated-either straight or angu- erally 25 to 28 presacral vertebrae; two sacral late; if dilated, lateral fleshy expansion ex- vertebrae generally present, rarely three or tending throughout length of digit; in some four; trunk vertebrae with continuous noto- cases only middle or distal, or both, parts of chord in adults and small, free intercentra; digits dilated; pilose friction pads commonly paired subcentral foramina present; neural present on digits; terminal subcaudal pi- arches of atlas paired or fused; tail rarely lose pads rarely present; if present, invari- 12 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 ably associated with arboreal activity. Nearly sauridae on the basis of their possession of all oviparous, laying one or two hard-shelled characters a-e and h listed above for that eggs. Heteropholis, Hoplodactylus, and Naul- family. For the genera Bavarisaurus and tinus bearing living young. Generally noc- Paleolacerta he proposed the subfamily turnal; if diurnal, species having either cra- Bavarisaurinae which differs from the Ardeo- nial or peritoneal pigmentation or both. Abil- saurinae only in the type of vertebrae (amphi- ity to vocalize generally present. coelous in the former subfamily and pro- RANGE: Circumglobal between latitude coelous in the latter). 500 S. and latitude 400 N. in the New World Hoffstetter considered the Ardeosaurinae and latitude 500 S. and latitude 500 N. in the to be "ancestral gekkonoids," but he did not Old World (map 1). Within this band gekkos visualize the subfamily as directly ancestral are found on all major land masses and on a to the Gekkonidae because of the single or majority of oceanic islands. only partially paired parietal and the presence FOSSIL HISTORY: It is now clear from the of procoelous vertebrae (he considered both recent works of Hoffstetter (1962; 1964) that characters advanced). The Eublepharinae, the lacertilian fauna of the Upper Jurassic clearly the most primitive living gekkonid was greatly varied (more than 15 genera and subfamily (see later discussion), also exhibit 21 species have been recognized) and that the these characteristics, and it seems likely that major evolutionary lines within the Sauria they are best treated as primitive features of were established by Middle Mesozoic. Hoff- the Gekkonoidea. Hoffstetter also stated that stetter's most recent paper (1964) has a direct the condition of paired premaxillaries in the bearing on the interpretation of the evolution Ardeosauridae differs from that of all modern of the Gekkonidae; for this reason his work is Gekkota. However, as is shown below in this briefly reviewed here. study, it is also characteristic of the primitive Hoffstetter recognized the three Jurassic eublepharine and diplodactyline gekkos. genera (Ardeosaurus H. von Meyer and The discontinuous postorbital arch of Eichstaettisaurus Kuhn from Bavaria, and Yabeinosaurus may indicate the forerunner Yabeinosaurus Endo and Shikama from Man- of that condition found in all Gekkonidae. The churia) as closely related to one another and absence of a pineal foramen from the representatives of the Gekkota, within which bavarisaurine genera (present in the Ardeo- he included them in the superfamily Gek- saurinae) also overcomes a major obstacle in konoidea. Further, he placed the three genera relating the Ardeosauridae to the Gekkoni- in the family Ardeosauridae (natural assem- dae, since this foramen is also absent from blage according to Hoffstetter) and defined the latter family. The large perforation at the it on the basis of the following characters: frontal-parietal suture in Paleolacerta may (a) premaxillaries paired; (b) complete supra- represent a juvenile developmental stage of temporal arch, consisting of two ossified the parietal and not the position of the supratemporal elements; (c) supratemporal iguanine pineal foramen. fenestra open; (d) jugal greatly extended Young (1959) tentatively placed the frag- dorsoposteriorly (in this manner the orbit is mentary Upper Jurassic Changisaurus mic- encircled by a complete bony ring, or with a rorhinus from South Chekiang, China, in the slight opening posteriorly, as in Yabeino- family Gekkonidae. From our present knowl- saurus); (e) parietals fused or partially so; edge of the osteology of the Gekkonidae (f) pineal foramen present and occupying a (Romer, 1956) it appears that Changisaurus central position in the body of the parietal; cannot be referred to this family. Baird (g) vertebrae procoelous (not verified for (1964) has shown that it is not a gekko and Eichstaettisaurus); and (h) completely de- suggested that it is a juvenile specimen of the veloped limbs, fifth metatarsal bent, and a extinct pleurosternoid turtle family Thalas- phalangeal formula of 2-3-4-5-3 (hand) and semyidae. 2-3-4-5-4 (foot). Hoffstetter also suggested Hoffstetter (1946) described three genera that the Bavarian genera Bavarisaurus Hoff- of gekkos from the Tertiary of France: stetter and Palaeolacerta Cocude-Michel may Rhodanogekko vireti from the Eocene, Caudur- be gekkonoids and related to the Ardeo- cogekko piveteaui from the Eocene-Oligocene, 1967 KLUGE: GEKKONID LIZARDS 13 and Gerandogekko arambourgi and G. gail- Hoffstetter (1946) described the genus lardi from the Miocene. The lack of im- Macrophelsuma from subfossil material of the portant diagnostic features on the avail- following modern species from the Mascarene able material makes it very difficult to place Islands: M. newtoni, Rodriguez Island; and these three genera in any one of the four M. cf. guentheri, Mauritius Island (today subfamilies recognized in the present study. known only from Round Island, about 25 The presence of sculpturing (or osteoderms?) kilometers northeast of Mauritius). Hoff- on the frontal of Hoffstetter's Rhodanogekko stetter's key diagnostic feature of Macrophel- is similar to the condition found in a few suma, that of fused parietals, cannot be used gekkonine genera, such as Geckonia and to separate it consistently from Phelsuma. some adults of Pachydactylus. The splenial Parietal fusion appears to be a function of age impression on the inner surface of the den- in these two groups of species, and therefore taries of Caudurcogekko and Gerandogekko I consider Macrophelsuma to be congeneric indicates that these genera are not related to with Phelsuma. In the same Mascarene Island the Sphaerodactylinae, because the splenial collection Hoffstetter recorded the presence is consistently absent from this subfamily. of modern Phelsuma cepediana and Hemidac- The extreme width of the frontal, between tylus cf. frenatus. the orbits, of Gerandogekko is similar to the Hecht (1951) described the extinct species condition found in many of the Gekkoninae Aristelliger titan from the Pleistocene or sub- and some of the Diplodactylinae, but un- Recent of Jamaica; however, Etheridge known in the Eublepharinae and Sphaero- (1965a) has suggested that it is conspecific dactylinae. The presence of amphicoelous with the modern Aristelliger lar. Hecht (1951) vertebrae in Gerandogekko definitely ex- and Etheridge (1964, 1965a) have found A. cludes it from any relationship with the com- lar in sub-Recent and Pleistocene cave de- pletely procoelous Eublepharinae and prob- posits in Haiti and the Dominican Republic ably the Sphaerodactylinae which are almost and the modern Thecadactylus rapicauda in completely procoelous. These data taken Pleistocene deposits of Barbuda, the West together, although admittedly scanty, sug- Indies. Hecht (1951) also reported on the gest that the three genera are probably more presence of modern Aristelliger praesignis closely related to the Gekkoninae than to the from Pleistocene or sub-Recent cave deposits other subfamilies. in Jamaica. On the basis of a single dentary, A single incomplete maxilla of a gekko is Koopman and Ruibal (1955) noted the known from the Miocene of Florida (Estes, presence of Tarentola americana in a cave 1963). I have examined this material and can deposit of possible pre-Columbian age from refer it to the family Gekkonidae, but not to Cuba. More recently, Etheridge (1965b) has a particular subfamily, because of the lack recorded T. americana in a Late Pleistocene of diagnostic features on the maxilla. In ad- fauna from New Providence Island, Ba- dition, the remains of two unidentified small hamas. gekkonids have been found in the Miocene At least three gekkonid lizards have been deposits of Beni Mellal, Morocco (Hoff- found preserved in resin: Platydactylus (?) stetter, 1961). minutus Giebel (1862), Hemidactylus viscatus The known Tertiary genera of gekkos Vaillant (1873), and Hemidactylus (Lygo- exhibit very few differences from modern dactylus) capensis (Peters, 1865, 1866; Cope, forms (Hoffstetter, 1946, 1961; Estes, 1963), 1868). The first two species are considered which suggests that the major changes asso- extinct, whereas the last form is believed to ciated with the evolution of the Gekkonidae be conspecific with a modern species. Un- occurred at a much earlier time. This evi- fortunately, the age of the resin and the dence, coupled with the suspected relation- locality at which it was collected are obscure, ships between the gekkos and the Jurassic with the exception of Peters' material that Ardeosauridae, adds further support to the came from Zanzibar. antiquity ascribed to the family Gekkonidae. THE SUBFAMILIAL CLASSIFICATION FEW ATTEMPTS HAVE BEEN MADE to organize known to occur there (see Appendix 1). These into natural groups the many genera of genera represent Underwood's proposed gekkonid lizards. The most recent and by far gekkonine and diplodactyline subfamilial the most comprehensive study is that of groups. The pupil was studied (1) in living Underwood (1954). He amassed a large specimens under different light intensities, amount of information and for the first time subdued, moderate, and intense, (2) in brought together evidence in support of inter- freshly killed specimens after either narcotiz- generic relationships and evolutionary trends. ing with nembutal or freezing, heating, or He also proposed some zoogeographical drowning had been employed, and (3) after hypotheses. One of Underwood's major different types of preservatives had been points was the delineation of presumed used, such as formalin or alcohol or combina- natural assemblages of genera. He recognized tions of both. Walls noted as early as 1932 three families: the Eublepharidae, the Sphae- (p. 69) that the shape of the pupil in living rodactylidae, and the Gekkonidae. The last animals rarely corresponds to that in the family, which contained more than 85 per preserved state. In the material studied by cent of the genera, was subdivided into two me (see Appendix 1) the shape of the pupil subfamilies, the Gekkoninae and the Diplo- varied greatly and did not appear to be cor- dactylinae, based on differences in the form of related with Underwood's definition of the the pupil. His information on the shape of the two subfamilies. The variability in certain pupil was obtained almost exclusively from species (e.g., Crenadactylus ocellatus) included preserved museum specimens. Underwood both emarginate and non-emarginate types defined the Gekkoninae as having an emargi- of pupils. It was relatively common to find nate vertical pupil and the Diplodactylinae, a the two types of pupils in different species in non-emarginate pupil (text fig. 1; pls. 1-5). the same genus (e.g., Diplodactylus; see pls. 2 and 3). My observations on non-Australian gekkos indicates the presence of pupil shapes that are intermediate between the gekkonine and the diplodactyline types (pl. 4). Some variation in pupil shape in other gekkos has been indicated earlier by Mann (1931), McCann (1955), and Cogger (1964); also see GEKKONINAE DIPLODACTYLINAE Denton (1956) and Werner (1965). From my FIG. 1. The major types of shape of the pupil observations it appears that the two major characteristic of the Gekkoninae and Diplodacty- subfamilies of gekkos, Gekkoninae and Di- linae as proposed by Underwood (1954). plodactylinae, cannot be distinguished from each other on the basis of pupil shape be- SHAPE OF THE PUPIL AS A SYS- cause of variability. In an attempt to delimit TEMATIC CHARACTER phyletic assemblages of genera in the Gekko- nidae, I have studied other characters, par- As I have discussed in an earlier paper ticularly osteological ones, as discussed be- (Kluge, 1964) and elaborate below, the shape low. of the pupil must be rejected as a diagnostic character differentiating the Gekkoninae ANALYSIS OF CHARACTERS from the Diplodactylinae. Because Under- It is generally agreed, where divergent wood's evolutionary and zoogeographical evolution has occurred, that similarity be- hypotheses were in a large part dependent on tween organisms indicates a close relation- the constancy of this single character, they ship. In related taxa, the character-states too must be reconsidered. that are homologous are those that were pres- During a 15-month study in Australia, I ent in their common ancestor. When the examined both living and preserved material character-states are dissimilar, at least one of almost all the genera and species of gekkos has diverged. 14 1967 KLUGE: GEKKONID LIZARDS 15 This section of the paper is devoted to the lids and the lack of a spectacle are considered determination and distribution of the char- the primitive condition. acter-states of 18 characters within the The functional significance of the modifi- Gekkonidae. Also, the relative primitiveness cation of the upper and lower eyelids into a of the character-states is suggested. The spectacle in gekkonid lizards has been con- evolutionary trends, from primitive to ad- sidered by M. A. Smith (1939) and Walls vanced, are inferred from the following pos- (1942). It is generally agreed by most her- tulates which are listed in order of signifi- petologists that the spectacle acts as an outer cance: protective covering for the cornea. The semi- 1. Character-states similar to those oc- fossorial South African genus Ptenopus ex- curring in fossil forms, presumed to be related hibits a high degree of corneal protection. to the ancestors of the modern groups, are Not only have the true eyelids fused to form a considered primitive. spectacle, but the upper and lower extra- 2. Character-states that are universal or brillar fringes have become extensively de- frequent in related modern groups (other veloped and movable and are analogous to families and subfamilies) are considered to be true eyelids. Ptenopus typifies the degree of primitive. The more widely the character- corneal protection found in many fossorial- state occurs among related taxa, the less terrestrial desert species of gekkos. Fossorial likely is it due to multiple parallel evolution activity and the wind-blown sand of arid and (Rule of Parsimony). semiarid regions appear to be particularly 3. Character-states that are universal or injurious to the eyes of terrestrial forms, and frequent within the taxonomic unit being it is possible that the spectacle evolved under studied are considered to be primitive (Rule such a selective pressure. There appears to be of Parsimony). little advantage for an arboreal form to have 4. Character-states confined to the group of a spectacle. True eyelids are present in (spec- taxa under study and occurring in those tacle absent from) all eublepharine genera. having the largest number of primitive fea- True eyelids appear to be absent from (spec- tures as determined by postulates (1), (2), tacle present in) all of the Diplodactylinae, and/or (3) are also considered primitive. Gekkoninae, and Sphaerodactylinae. It seems Sporne (1954) has shown that the probability likely that the brille-spectacle condition of that the character-state is primitive increases these three subfamilies has been derived from very rapidly with the increase in the number the primitive condition exemplified by the of primitive characters with which it is cor- Eublepharinae. related. b-B. PREMAXILLARY BONE a-A. TRUE EYELIDS The premaxilla is the most anterior median OR SPECTACLE dermal element of the skull. In adult Squa- mata this bone is invariably single, except in Bellairs (1948) demonstrated that the the Scincidae, in which it is generally paired, presence of true upper and lower eyelids and and the Gekkonidae, in some forms of which absence of a spectacle (brille) in the euble- it is paired. The primitive gekkonid pre- pharine genus Coleonyx are similar to the maxilla appears to have been paired, as in- typical saurian condition. It appears that the ferred from the paired condition found in the spectacle of all non-eublepharine gekkos, as in ancestral Ardeosauridae (see pp. 12, 13). some scincid and teiid lizards, and snakes, There are two types of premaxillary devel- evolved from the more primitive upper and opment in gekkonid lizards. The first type, lower eyelids through fusion and that extra- apparently restricted to the Eublepharinae brillar fringes are secondary developments. and Diplodactylinae, is shown in figure 2A. Both the upper and lower extra-brillar fringes The premaxilla is paired at the prehatchling may be greatly developed and give the ap- egg-tooth stage in these two subfamilies and pearance of true eyelids but may be partly or doubtless forms from two separate centers of wholly analogous depending on the extent of ossification. Figure 2B shows the same paired their development. The presence of true eye- condition in the viviparous genera of the 16 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 rowness of the nasal process and the forma- tion of the unique birdlike beak. A split was present in the dorsal margin of the nasal process of the premaxilla in two adult specimens of the gekkonine genus Rhoptropella and in one of Tropiocolotes tripolitanus. Other specimens of different age groups of both of these species show no indi- cation of a split or two embryonic centers of ossification. The few exceptional specimens probably exhibit bone fracturing, a moder- ately common populational variation without A B C apparent genetic foundation. FIG. 2. Anterior view of the premaxilla in pre- It appears that the primitive gekkonoid hatchling specimens of approximately the same condition of the premaxilla has been retained age, showing the paired and single centers of in the Eublepharinae, Diplodactylinae, and ossification. A. Coleonyx v. variegatus, oviparous, Ardeosauridae. The single premaxilla found with paired egg teeth. B. Hoplodactylus granulatus, in the Gekkoninae and Sphaerodactylinae live-bearer, without specialized egg teeth. C. seems to have been derived from the paired Lepidodactylus lugubris, oviparous, with paired the loss of the two centers of egg teeth. condition by ossification during a very early stage of em- bryogenesis. Diplodactylinae at a stage equivalent to that of the prehatchling egg tooth. c-C. ENDOLYMPHATIC APPARATUS The second type of premaxillary develop- ment appears to be restricted to the Gek- The endolymphatic apparatus of verte- koninae and Sphaerodactylinae. As shown in brate animals consists of a narrow canal, the figure 2C, at the prehatchling egg-tooth stage, endolymphatic duct, and its terminal en- the premaxilla is a single element which ap- largement, the endolymphatic sac, which is pears to form from a single center of ossifica- variable in size and shape. In general, the tion. I have not been able to find paired duct arises from the sacculus of the mem- centers of ossification at the inception of pre- branous labyrinth of the inner ear, passes maxilla formation by staining with Alizarin through the endolymphatic foramen into the red-S. cranial vault, and expands into the endolym- In adult Eublepharinae and Diplodacty- phatic sac. The sac lies in the interdural space linae either the paired embryonic condition of in the cranial vault of lower vertebrates the premaxilla is retained, or the suture is (Whiteside, 1922). This space lies between reduced to a notch or split in the dorsal mar- the two layers of the dura mater and is some- gin of the nasal process, or lost. In both of the times referred to as the lymphatic space. The above subfamilies the paired premaxilla and endolymphatic sac is a large, thin-walled split or notched nasal process was found in 81 vesicle surrounded by a connective tissue per cent of the total number of specimens ex- sheath and appears to develop at a somewhat amined (see Appendix 1). Almost all of the slower rate than the associated duct. The sac remaining 19 per cent, which showed no indi- subdivides into numerous small compart- cation of the paired embryonic state, were ments (tubuli) during the course of develop- adults of maximum size; apparently bony ment and gradually becomes surrounded by material had filled in the fissure in the course a dense vascular network. The tubuli re- of aging. Only in a diplodactyline species peatedly divide to give the sac the appear- Rhynchoedura ornata was the paired condition ance of a tubular ductless gland, The walls of evident in juveniles but not in subadults or the sac are glandular and are derived from the adults. The absence of any indication of the labyrinth of the inner ear, the epithelium of paired preadult state from Rhynchoedura is which can produce calcareous substances. probably correlated with the extreme nar- The production of calcareous materials is 1967 KLUGE: GEKKONID LIZARDS 17 found in the endolymphatic apparatus of all for bone growth. The question of function is vertebrate classes (Whiteside, 1922). still open for study. For example, Ruth The endolymphatic sac is filled with an (1918) found some evidence in gekkos to sug- amorphous milky fluid (presumed to be gest that the sporadic occurrence of the cal- largely calcium carbonate-calcite and arago- careous material in the gland is correlated nite are the more common forms) which with the time of eggshell formation, and hardens upon exposure to air and certain pre- Kastle (1962), who studied Lygodactylus servatives. Little is known about the prop- picturatus and Phelsuma d. dubia, described erties of the secretion. Sterzi (1899) stated the neck swellings as "seasonal" in females. that light was refracted in the fluid form and In a presumably analogous situation, how- that the secretion exhibited Brownian move- ever, Etheridge (MS) found no relationship ment, but even these initial observations between sex or size and the amount of calcifi- have not been reinvestigated. cation in two species of the iguanid genus The endolymphatic apparatus is basically Anolis. similar in all vertebrates with the exception Calcified endolymphatic sacs in the post- of certain ascalabotan lizards. In general, the cranial region appear to be absent from all sac is small and restricted to the cranial vault Eublepharinae and Diplodactylinae. The and to the more proximal part of the verte- complete absence of the sac in the neck re- bral canal; it is almost invariably filled with gion (i.e., in an uncalcified state), however, some calcium carbonate during embryogene- must be further investigated histologically in sis, and apparently to a greater degree during these subfamilies. It appears that in the adult life. In some Ascalabota, Iguanidae Gekkoninae and all Sphaerodactylinae post- (Aptycholaemus, Polychrus and the anoles, cranial calcified sacs are present (the calcified Anolis, Chamaeleolis, Chamaelinorops, Phen- condition has not been confirmed for the fol- acosaurus, and Tropidodactylus; see Ethe- lowing gekkonine genera: Agamura, Blaeso- ridge, MS), and Gekkonidae, the sac becomes dactylus, Saurodactylus, Teratoscincus, and greatly enlarged and protrudes from the Thecadactylus). cranial vault between the parietal and sup- Apparently the greatly enlarged post- raoccipital elements (e.g., Tarentola m. mauri- cranial extension of the endolymphatic sac, as tanica) or through the vagus foramen (e.g., found in the Gekkoninae and Sphaerodacty- Gekko g. gecko) and lies along the surface of linae, is a specialized condition derived from the peripheral lateral neck musculature (pl. an intracranial vault form. The different 5, figs. 2, 3). Camp (1923) reported the pres- points of exit from the cranial vault, as noted ence of calcified sacs in the Xantusiidae (a above, suggest the possibility of parallel group of lizards referred to the Ascalabota by evolution within the Gekkoninae. some systematists), but I have not been able to verify their presence in any member of d-D. PREANAL ORGANS AND that family. The posterior extension of the ESCUTCHEON SCALES endolymphatic apparatus from the cranial The glandlike preanal organs of lizards vault and the presence of calcium carbonate have been discussed in some detail by Camp appear to be specializations that have evolved (1923) and M. A. Smith (1935). These organs in parallel in the Iguanidae and the Gekko- appear to be simple tubular invaginations of nidae. the epidermis, and the secretion is apparently The function of the endolymphatic system odorless and is believed to be composed and its secretion is poorly understood. Early chiefly of epidermal scales. It seems that the workers (see Whiteside, 1922, for summary) various nominal groupings of these organs, hypothesized that the apparatus regulates such as femoral, inguinal, and anal, simply pressure in the labyrinth by removing the refer to regional concentrations of the same endolymph from the sacculus, acts as an aid structures; therefore they are all treated here in the transmission of sound waves from the as preanal organs. The homology of the post- skull into the ear, is analogous to cranial anal organs in some scincid lizards (e.g., meninges in protecting the central nervous Tropidophorus) is questionable. In general, system, and is a source of calcareous material preanal organs appear to be similar to mam- 18 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 malian sebaceous glands (Felizet, 1911), al- pears more likely that escutcheon scales though both M. A. Smith (1935) and H. evolved from femoral organs (postulate 4; see Smith (1960) stated that the structures are character-groups, table 2). There is some sim- not glands, without elaborating on the ilarity (almost certainly coincidental) be- point. Cole (1966) recently studied histo- tween the general shape of the area covered logical preparations of these structures from by escutcheon scales in sphaerodactyline the iguanid Crotaphytus collaris and has dem- gekkos and the patch of femoral pores found onstrated that glandular activity does in the diplodactyline genera Naultinus, occur (also suggested by Greenberg, 1943, for Heteropholis, Hoplodactylus, Carphodactylus, Coleonyx). It has been recognized for some and Bavayia. There is no evidence that sug- time that the external orifice (preanal pore) gests that the Sphaerodactylinae were de- of a single organ is more actively engorged rived from the Diplodactylinae, or vice versa. with the waxy cellular debris during certain Pasteur (1964) briefly noted that an escutch- seasons. The activity seems to be correlated eon analogue may occur in the gekkonine with the sex cycle. Additional evidence sup- Lygodactylus and related groups, but such has porting such a correlation comes from the fact not been verified by further study (Paul that the pores are almost exclusively re- Maderson, personal communication). Taylor stricted to males and that when present in and Leonard stated that escutcheon scales females they are much smaller and in most may serve the same general function as cases underdeveloped. The external aperture femoral organs. of the organ occurs either in the center of the Preanal pores are present in all eublepha- scale or at its posterior margin. Homologous rine genera except Holodactylus. In the Di- scales in females are occasionally indented plodactylinae, they have been found in 11 out and suggest the male pore arrangement; of 23 species of Diplodactylus and in all other however, the epidermal layer is almost in- genera except Nephrurus and Phyllurus variably imperforate. (Kluge, MS). They are absent from the Although preanal pores are conspicuous Sphaerodactylinae and approximately one- saurian features, the exact function of the half of the gekkonine genera. Escutcheon organs is poorly understood. Greenberg scales appear to be restricted to the Sphaero- (1943) has provided the best evidence for dactylinae. their function in gekkonid lizards. He stated It appears that preanal organs have been that, during courtship in Coleonyx, the male lost independently in all major gekkonid rubs the wax cones protruding from the pores groups with the possible exception of the transversely across the tail of the female. She Sphaerodactylinae. Furthermore, it seems responds to the rubbing by elevating her tail, likely that there has been multiple parallel a necessary preliminary to the actual act of loss of these organs within the Gekkoninae in copulation. The pores are present in most view of their absence from so many morpho- lizard groups, and presumably they were logically different genera. The escutcheon present in ancestral lizards. scales of the Sphaerodactylinae are almost Escutcheon scales (apparently analogous certainly modified preanal organs. to the callose scales of agamid lizards; M. A. Smith, 1935, pp. 132, 211, fig. 56) are special- e-E. ABILITY TO VOCALIZE ized glandular scales lacking pigment on the Almost all the characters used in this study ventral aspect of the abdominal, femoral, and are well documented with the exception of the postcloacal regions (Taylor and Leonard, distribution of vocal ability and the number 1956). These scales are more distinctly modi- of eggs deposited at a single laying (number fied in males than in females and appear to in- of young born in viviparous species, sensu crease in number with age. It has been sug- kato; see character f-F). These features appear gested by Noble and Bradley (1933) and by to show considerable promise in the elucida- Taylor and Leonard (1956) that these scales tion of the relationships within the family, are structures from which preanal organs in but, by the very nature of the characters other groups were derived, but there is no themselves, little information has been ac- clear evidence for this suggestion and it ap- cumulated on them. The following discussion 1967 KLUGE: GEKKONID LIZARDS 19 of vocal ability and that on the number of 4). The reduction in egg number in the Sphae- eggs laid are based on cursory observations rodactylinae and the presence of viviparity that I have made during the past six years, in the Diplodactylinae are considered ad- both in the field and laboratory, and from a vanced character-states. review of the literature. These characters al- most certainly will require more detailed g-G. SUPRATEMPORAL BONE future studies. The application of the names "supratem- Among gekkonids, all sphaerodactylines poral" (=tabular) and "squamosal" to the appear to be voiceless, whereas all Euble- two small dermal temporal elements in rep- pharinae and certainly most oftheGekkoninae tiles was extensively reviewed by Camp and Diplodactylinae that have been investi- (1923). From the observations of Underwood gated actively vocalize (Underwood, 1954). (1957) and Kluge (1962) and additional in- It has been suggested by Underwood (1962) formation presented here, it appears that the that in gekkos there may be a correlation be- squamosal (the lateralmost element) persists tween voicelessness and an environment in and the more medial supratemporal has been which illumination is great enough to permit lost in most gekkonid lizards. These findings visual cues, which may explain the condition are in contradiction to Camp's supposition found in the voiceless, diurnal (shade-in- that the supratemporal persists and the habiting) Sphaerodactylinae. However, at squamosal is lost. Camp, who lacked the least some diurnal gekkonines and diplodac- critical material, was unaware of the evolu- tylines actively vocalize (e.g., Naultinus). tionary sequence in the Eublepharinae The presence of vocal ability probably rep- (Kluge, 1962) that conclusively shows the resents the primitive character-state in loss of the supratemporal (the inner element) gekkonids as inferred from its distribution and the persistence of the squamosal (e.g., in among the more primitive subfamilies, Euble- Eublepharis macularius and E. kuroiwae pharinae, Diplodactylinae, and Gekkoninae orientalis the squamosal is large and the sup- (postulate 4). The absence of this character- ratemporal is small, in E. hardwickii the state from the Sphaerodactylinae and non- squamosal is large but the supratemporal has gekkonids probably represents a condition been finally lost; fig. 3). The presence of the arrived at in parallel. supratemporal is doubtless the primitive character-state in gekkonid lizards (Romer, f-F. NUMBER OF EGGS LAID 1956). For introductory remarks on the number of The supratemporal and squamosal eggs laid, see character e-E (Ability to Vocal- strengthen the complex quadrate-opisthotic- ize). All the Eublepharinae that I have been parietal articulation. Maximum strength is able to observe lay two eggs. The Diplodac- attained when both the supratemporal and tylinae also lay two eggs with the exception the squamosal are present, the minimum of the three New Zealand genera, Heteropho- when both elements are absent. lis, Hoplodactylus, and Naultinus, which bear The supratemporal was found in the Euble- living young. So far as known, all the Sphaer- pharinae in both species of Aeluroscalabotes, odactylinae lay one egg, and the Gekkoninae Eublepharis macularius and E. kuroiwae lay two (Aristelliger is exceptional in laying orientalis, and in Holodactylus africanus. The only one). The laying of a single egg may be absence of the supratemporal has been con- related to small adult size in the Sphaero- firmed from the Eublepharinae in Eublepharis dactylinae, but the smaller gekkonine genera hardwickii, from both Hemitheconyx species that I have studied (e.g., Lygodactylus) do not (wrongly stated by Underwood, 1957, as follow this hypothesis. In the sphaerodacty- being present in H. caudicinctus), and from line genera Gonatodes and Sphaerodactylus, all Coleonyx. The supratemporal is absent both right and left ovaries and oviducts are from all of the Diplodactylinae, Gekkoninae, fully matured and appear to alternate in the and Sphaerodactylinae. It seems reasonable production of a single egg. The laying of two to suggest that the supratemporal was lost in eggs is probably the primitive character-state the ancestral stock leading to the latter sub- in the Gekkonidae (as inferred from postulate families, and the loss did not happen inde- 20 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 /

SQUAMOSAL

& SUPRATEMPORAL

FORAMEN MAGNUM

ORDER OF EVOLUTIONARY CHANGE 1. SUPRATEMPORAL - LOST 2. SQUAMOSAL- LOST 3. PAROCCIPITAL PROCESS- GREATLY REDUCED, ULTIMATELY LOST 4. QUADRATE- MOVES UND.ER PARIETAL, ARTICULATES WITH PROOTIC FIG. 3. Evolution of the temporal region in the Gekkonidae. Dorsal view of the pos- terior portion of the cranium of a hypothetical primitive gekko, with the major cranial bones and other points of reference indicated. The order of evolutionary change from primitive to advanced is listed below the drawing. pendently in the three groups. As inferred that developed directly from the scleroid from the character groupings, it is possible layer (Romer, 1956) and are not, as once that this loss occurred within the Euble- thought, homologous to the circumorbital pharinae. ring of dermal bones of primitive vertebrates. Fossil evidence suggests that a ring of bony h-H. NUMBER OF SCLERAL OSSICLES plates was present in primitive vertebrates Scleral ossicles are small, thin, ossified, and has been maintained in all main lines of cartilaginous plates embedded in the scleroid evolution, although in living forms they are coat of the eyeball (Edinger, 1929). They with certainty known only in actinopterygian form an interrupted or continuous ring of one fishes, birds, and most reptiles (Piveteau, to 40 elements radiating from the edge of the 1955, 1966). Scleral ossicles have not been cornea. These plates should not be confused found in chondrichthyan fishes, modern with the cartilaginous orbital cup, which oc- crocodilians and mammals, or snakes. They casionally also ossifies, but lies completely are presumed to be absent from modern am- outside the eyeball proper. It is now believed phibians, although small, irregularly shaped that scleral ossicles are neomorphic elements bony elements have been found in a salaman- 1967 KLUGE: GEKKONID LIZARDS 21 drid salamander (Cynops pyrrhogaster subsp.) represented by 111 eyeballs. The range of and a microhylid frog (De Beer, 1937; Walls, variation is 13 to 25 ossicles, with a mean of 1942), but here the homology is questioned. 16.7 and 2.7 as the average deviation of the The apparent parallel loss of these structures means of the genera (fig. 4). The mean of 16.7 in the differently adapted major vertebrate is not truly representative of the subfamily, groups is difficult to explain on the basis of a because Coleonyx, the genus with the lowest common adaptive shift due to similar forces number of ossicles, is represented by the of natural selection. The function of scleral greatest number of specimens: 96 specimens ossicles is still unsolved. Walls (1942) con- of Coleonyx as compared to seven of Euble- sidered that at least for sauropsidian (reptile pharis, the next highest. The mean for and bird) vision they assist in accommoda- Coleonyx alone is 16.1. I believe that this is tion by maintaining the over-all shape of the the result of a secondary reduction from a eyeball. In some birds they appear to main- higher, more primitive eublepharine number, tain the asymmetry of the eyeball so that possibly represented today by that of Aeluro- binocular vision can be realized (Slonaker, scalabotes. Some support for this thesis is 1918). gained from the following points: (1) on the Apparently the number of scleral ossicles basis of the large number of other characters has never been considered a major diagnostic (see remaining discussions of subfamilial character in any of the vertebrate classes. It diagnostic characters), Aeluroscalabotes is is therefore surprising that in a relatively considered to be the most primitive surviving small group, such as the Gekkonidae, ossicles eublepharine genus and very near the an- appear to be a significant indicator of rela- cestral stock of the subfamily, and it there- tionships. The extreme numerical differences fore seems reasonable to assume that the among the gekkonid subfamilies may provide higher number is part of the primitive genetic the necessary material for a better under- background of the group; (2) the nearest standing of the function of these elements in relative of Coleonyx is clearly the slightly all vertebrates. more primitive Eublepharis (Kluge, 1962) Gugg's (1939) comprehensive study of which exhibits a higher ossicle number, ap- modern rhynchocephalian and lepidosaurian proaching that of Aeluroscalabotes; and (3) ossicles suggests that the primitive number the Diplodactylinae exhibit extremely high may be about 14. The number of ossicles ossicle numbers and are believed to have been varies very little in lepidosaurians with the derived from a primitive eublepharine, pos- exception of some gekkonids. All the ossicle sibly near Aeluroscalabotes. It is therefore data on gekkonid lizards compiled in the pres- postulated that the mean ossicle number of ent study is included in table 1. Additional 24.0 of Aeluroscalabotes is closer to the primi- ossicle counts can be obtained from Under- tive condition for this subfamily. The remain- wood's (1954, 1957) general studies on gekkos ing four genera appear to show stepwise re- and pygopodids, and from the works of Ste- ductions, culminating in the low number of phenson (1960) and Stephenson and Stephen- Coleonyx, which only coincidently approxi- son (1956) on Australian and New Zealand mates the common lacertilian number of 14. gekkos, respectively. In obtaining the ossicle DIPLODACTYLINAE: All the 14 genera that I numbers given in table 1, I counted all the have referred to the Diplodactylinae have bony plates, including the occasionally much- been examined. Of these 14 genera, counts reduced dorsal and ventral elements. Care were accumulated on 44 species and sub- was taken, however, not to count the splinter- species, represented by 260 eyeballs. The like fragments produced by extraction of the range of variation is 21 to 40 ossicles per eye- eyeball from its socket. The greatest degree ball, with a mean of 31.9 and 3.8 as the aver- of accuracy in counting the ossicles is age deviation of the means of the genera achieved by using preserved specimens, be- (fig. 4). fore they have been cleared and stained. Stephenson (1960), after studying small EUBLEPHARINAE: All of the five recognized numbers of juvenile and adult specimens of eublepharine genera (Underwood, 1954) were Nephrurus, suggested that the ossicle number examined, including 11 species and subspecies decreased with age. From Stephenson's ac- 22 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135

EUBLEPHARINAE 5-11-__l

DIPLODACTYLINAE 14-44-260

GEKKONINAE- GROUP II E$ZZ. 56-191-508 GEKKONINAE- GROUP IL II 2-12-40 SPHAERODACTYLINAE Eli 5-20-67

a p p~ 10 20 30 40 NUMBER OF SCLERAL OSSICLES FIG. 4. Range of variation, mean, and average of the deviations of the means of the genera for the Eublepharinae (five genera, 11 species and subspecies, 111 specimens examined), Diplodactylinae (14 genera, 44 species and subspecies, and 260 specimens examined), Gekkoninae Group I (56 genera, 191 species and subspecies, and 508 specimens examined), Gekkoninae Group II (two genera, 12 species and subspecies, and 40 specimens examined), and Sphaerodactylinae (five genera, 20 species and subspecies, and 67 specimens examined). count it was not clear if the reduction oc- n2= 18. A corner test of association also indi- curred by loss or fusion. My observations, cated that the number of ossicles does not however, do not support the contention that decrease with age in Phyllurus milii. All the ossicles are lost or fused in ontogeny in any specimens of P. milii used in this example are species. Counts on Phyllurus milii (fig. 5), a from a single deme at Bakers Hill, Western member of the genus most closely related to Australia. Nephrurus (Kluge, MS), indicate that there is The Diplodactylinae show affinity to the almost as great a degree of variation in a Eublepharinae by reason of their increase in single individual (comparing right and left ossicle number; it is proposed that both sub- eyeballs) as there is between juveniles (snout- families were derived from an ancestral form to-vent length, 38 mm.) and adults (89 mm.). that possessed an ossicle number higher than An analysis of variance was applied to the 14. The more primitive diplodactyline genera, data in figure 5, and it was concluded that the Crenadactylus, Eurydactylodes, Heteropholis, estimated variance between the column Hoplodactylus, Naultinus, and Phyllurus means (snout-to-vent lengths for 28, 29, 30, (Kluge, MS), exhibit mean scleral ossicle and 31 scleral ossicle counts) is significantly counts in the low- to mid-twenties (range 21 less (at P = 0.001) than the estimated vari- to 29) around that of the most primitive ance within the columns: F=2.282, ni=3, eublepharine genus Aeluroscalabotes (23 to 1967 KLUGE: GEKKONID LIZARDS 23 32

w -J O 31 . xa x cn(I) 0 < 30 X xx X id J- I I X 0 29 x Xxxx w 0 cr W 28 I. x x

Z.

2 a 0 2 ==NJ 27 L _ 3CD 40 50 60 70 80 90 100 SNOUT-TO-VENT LENGTH IN MM. FIG. 5. Number of scleral ossicles (X) graphed against snout-to-vent length in 11 juvenile and adult Phyllurus milii from Western Australia. In those cases in which the number of ossicles is different in the two eyeballs from the same individual, they are connected by a vertical line to indicate the range of variation in that individual. 25). This correlation may suggest that the in males; (5) scleral ossicles 14 or 15; (6) ancestral number of the Diplodactylinae was angular absent; and (7) squamosal present. in the low- to mid-twenties. In accord with the morphological uniformity GEKKONINAE (GROUP I): Included in this of the species, the geographical range of the group are 56 genera and 191 species and sub- genus appears to be continuous through species, represented by 508 eyeballs. The Afghanistan, Iran, West Pakistan, and range of variation is 13 to 17, with a mean of Turkestan. 14.0 and 0.2 average deviation of the means GEKKONINAE (GROUP II): Group II con- of the genera (fig. 4). sists of two genera, Stenodactylus and Terato- Stenodactylus lumsdenii, S. orientalis, and scincus, of which 12 species and subspecies, S. maynardi belong to Group I and are re- represented by 40 eyeballs, have been ex- ferred to the genus Crossobamon. Crossobamon, amined. The range of variation in number of with these three forms included, has a great ossicles is 15 to 28, with a mean of 21.7 and deal of external morphological and osteo- 3.4 average deviation of the means of the logical uniformity, almost certainly indica- genera (fig. 4). The ossicle number was not tive of a natural assemblage of species. The determined for Stenodactylus arabicus genus is characterized by (1) straight, undi- (=haasi), but, on the basis of its external lated digits, with a lateral fringe or denticula- morphological similarity and geographical tion of pointed scales, subdigital surfaces proximity (Haas, 1957; Anderson, 1896), it covered with transverse lamellae; (2) nasal also appears to belong to this group. region not noticeably swollen; (3) dorsal body All the species thus far examined in Group scalation heterogeneous, consisting of gran- II exhibit some similarity in the shape and ules and scattered, enlarged, keeled tubercles; scalation of the digits, as well as in an in- (4) preanal pores almost invariably present creased ossicle number. These characters 24 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 taken together seem to indicate that the now contains a well-circumscribed group of species form a natural group. The increased species restricted to the Sahara Desert and ossicle number found in this assemblage may eastern coast of Africa, as far south as Kenya, have arisen directly from that of the Euble- to Arabia, Iraq, Israel, Jordan, Lebanon, and pharinae and Diplodactylinae. The presence Syria. of the angular in Teratoscincus (a primitive SPHAERODACTYLINAE: All the five genera gekkonid feature found elsewhere only in the that are referred to this subfamily have been Eublepharinae) strongly supports this con- examined. This includes 20 species and sub- tention. If confirmed, the absence of a calci- species, represented by 67 eyeballs. The fied postcranial extension of the endolym- range of variation of the number of ossicles is phatic apparatus from Teratoscincus (al- 12 to 15, with a mean of 14.0 and 0.1 as the though present in Stenodactylus) can also be average deviation of the means of the genera cited as additional evidence. The correlation (fig. 4). between the largest ossicle number of Group In summary, it appears that the primitive II and that of the Eublepharinae and that of scleral ossicle number in gekkonid lizards was the more primitive diplodactyline genera in the low- to mid-twenties; this condition has (Crenadactylus, Eurydactylodes, Heteropholis, been retained in three distinct evolutionary Hoplodactylus, Naultinus, and Phyllurus; see lines. The more primitive eublepharines, table 1) is considered significant. Aeluroscalabotes and Eublepharis, seem to The two genera that belong to Group II have retained the primitive number, whereas (Stenodactylus and Teratoscincus) are easily the other genera in the subfamily (particu- distinguished from each other osteologically. larly the specialized Coleonyx) exhibit step- The angular is absent from the former genus wise reductions in ossicle numbers. In con- and present in the latter, and the squamosal trast to this trend in the Eublepharinae, the is present in the former genus and absent more specialized genera in the Diplodacty- from the latter (see subfamilial diagnostic linae (second evolutionary line)show a marked character discussions of the angular and increase in ossicle number which culminates squamosal). These osteological differences in 40 per eyeball. The gekkonine Group II, suggest that the group, if a natural one, has which includes only Stenodactylus and Terato- been isolated for a relatively long period of scincus, represents the third evolutionary time. line. The significantly lower ossicle numbers On the basis of their large number of ex- found in the Gekkoninae (Group I) and Sphae- ternal (meristic and mensural) and internal rodactyl-inae were probably derived from an morphological similarities, I have transferred ancestral condition in the low- to mid- Ceramodactylus major, Pseudoceramodactylus twenties. The trend in the reduction of the khobarensis, and Trigonodactylus arabicus to number of ossicles in the Eublepharinae may Stenodactylus (see table 1). Stenodactylus indicate the steps by which the Gekkoninae arabicus Haas (1957, p. 56) is preoccupied by (Group I) and Sphaerodactylinae reverted to Stenodactylus (Trigonodactylus) arabicus Haas near the "standard" lacertilian number of 14. (1957, p. 51). I here propose the name haasi, The selective pressure that holds the Gek- nomen novum for arabicus Haas (1957, p. 56). koninae and Sphaerodactylinae to this lower Stenodactylus is now defined by the following number may not be so strong as that acting characters: (1) digits relatively long, straight, on most other non-gekkonid lizards, as in- variable in width, bordered by lateral fringe ferred from the degree of ossicle variation of pointed scales, subdigital scales small, found in the two subfamilies. carinate or triangular, transverse lamellae absent; (2) nasal region usually markedly i-I. CLOACAL SACS AND BONES swollen; (3) dorsal body scalation homo- Cloacal sacs are moderately large, paired geneous, consisting of smooth or pointed invaginations situated slightly posterior to granules; (4) preanal pores almost invariably the vent. The distance between the external absent from males; (5) scleral ossicles 20 or orifice of the sac and the vent varies mark- more; (6) angular absent; and (7) squamosal edly in different species. These pockets are present. Geographically, this expanded genus unique to the Gekkota. They are invariably 1967 KLUGE: GEKKONID LIZARDS 25 TABLE 1 THE NUMBER OF SCLERAL OSSICLES PER EYEBALL IN THE SUBFAMILIES EUBLEPHARINAE, DIPLODACTYLINAE, GEKKONINAE, AND SPHAERODACTYLINAE No. of Scleral Ossicles No. of Eyeballs (Range and Mean) Eublepharinae Aeluroscalabotes dorsalis dorsalis 4 23-25 (23.8) felinus 1 25 Coleonyx brevis 16 15-18 (16.3) elegans elegans 2 16 mitratus 2 14-15 (14.5) variegatus" 76 13-19 (16.1) Eublepharis hardwickii 2 17-18 (17.5) macularius 5 15-19 (17.6) Hemitheconyx caudicinctus 1 18 Holodactylus africanus 2 18-22 (20.0) Diplodactylinae Bavayia cyclura 3 32-33 (32.7) sauvagii 2 31-34 (32.5) Carphodactylus laevis 4 30-33 (31.8) Crenadactylus ocellatus 16 22-27 (24.3) Diplodactylus alboguttatus 2 33-34 (33.5) byrnei 2 32 ciliaris ciliaris 5 33-37 (35.0) ciliaris intermedius 20 30-34 (31.4) conspicillatus 4 31-34 (32.0) damaeus 14 37-40 (37.9) elderi 2 30 maini 4 32-33 (32.8) pulcher 10 30-38 (34.3) savagei 2 25-27 (26.0) spinigerus 9 31-36 (33.3) steindachneri 2 32 stenodactylus 16 34-39 (36.6) strophurus 4 31-32 (31.5) taenicauda 6 30-35 (33.1) tessellatus 5 34-38 (36.8) vittatus 24 33-38 (36.3) williamsi 6 29-35 (32.7) Eurydactylodes vieilardi 1 27 Heteropholis tuberculatus 2 21-22 (21.5) Hoplodactylus duvaucelii 6 24-26 (25.0) granulatus 8 23-27 (25.4) 26 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 TABLE 1-(Continued) No. of Scieral Ossicles No. of Eyeballs (Range and Mean) pacificus 6 26-29 (27.2) Naultinus elegans 4 22-23 (22.5) Nephrurus asper 4 30-33 (31.5) laevissimus 2 29-33 (31.0) levis levis 10 32-36 (34.6) wheeleri wheeleri 2 32-33 (32.5) Oedura lesueurii lesueurii 4 32-34 (32.5) marmorata 2 34-35 (34.5) monilis 2 32-34 (33.0) robusta 2 31-32 (31.5) tryoni 2 29-30 (29.5) Phyllurus cornutus 4 25-27 (26.0) milii 20 28-31 (29.4) platurus 4 25-28 (26.5) sphyrurus 2 27-29 (28.0) Pseudothecadactylus australis 2 31-32 (31.5) Rhacodactylus auriculatus 2 29-30 (29.5) Rhynchoedura ornata 8 32-37 (34.6) Gekkoninae (Group I) Afroedura pondolia pondolia 2 14 transvaalica platyceps 2 14-15 (14.5) Agamura persica 3 14 Ailuronyx seychellensis 2 14 Alsophylax pipiens 1 14 Aristelliger cochranae barbouri 4 14 praesignis praesignis 6 14 Blaesodactylus boivini 2 14 Bogertia lutzae 1 14 Briba brasiliana 3 14 Bunopus tuberculatus 2 14 Calodactylodes aureus 2 14 Chondrodactylus angulifer 2 15-16 (15.5) Cnemaspis affinis 1 14 africana 1 14 1967 KLUGE: GEKKONID LIZARDS 27 TABLE 1-(Continued) No. of Scleral Ossicles No. of Eyeballs (Range and Mean) boulengersii 1 14 indica 1 14 kandiana 3 14 kendallii 2 14 nigridius 1 14 ornata 1 14 quattuorsersata quattuorseriata 2 14 siamensis 2 14 wynadensis 2 14 Cobpus wahlbergii 3 14-15 (14.7) Cosymbotus platyurus 2 14 Crossobamon eversmanni 2 14 lumsdenii 1 14 maynardi 3 14-15 (14.3) orientalis 4 14-15 (14.3) Crytodactylus agusanensis 1 14 angularis 1 14 annulatus 3 14 baluensis 1 14 brevipalmatus 1 14 caspius 1 14 cavernicolus 1 14 collegalensis 1 14 condorensis 1 14 consobrinus 1 14 darmandvillei 1 14 feae 1 14 fedtschenkoi 1 14 fraenatus 2 14 fumosus subsp. 1 14 intermedius 1 14 irregularis 1 14 jellesmae 1 14 kachhensis watsoni 2 14-15 (14.5) khasiensis subsp. 1 14 kirmanensis 1 14 kotschyi subsp. 1 14 kotschyi oertzeni 1 14 lateralis 1 14 lawderanus 1 14 loriae 1 14 louisiadensis 2 14 malayanus 1 14 malcolmsmithi 1 14 marmoratus 2 14 mimikanus 1 14 nebulosus 1 14 oldhami 1 14 papuensis 1 14 28 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VIOL. 135 TABLE 1-(Continued) No. of Scleral Ossicles No. of Eyeballs (Range and Mean) peguensis subsp. 1 14 pelagicus pelagicus 2 13-14 (13.5) philippinicus 1 14 pubisulcus 1 14 pulchellus 1 14 redimiculus 1 14 rubidus 1 14 russowii 1 14 scaber 2 14 serpensinsula 1 14 stoliczkai 1 14 triedrus 1 14 vankampeni 1 14 wetariensis 1 14 Dravidogecko anamallensis 1 14 Ebenavia inunguis 2 14 Geckolepis maculata 2 14-15 (14.5) Geckonia chazaliae 2 14 Gehyra austratis 2 14 mutilata 6 14 oceanica 4 14 punctata 20 13-16 (14.2) variegata 20 14-16 (14.3) Gekko athymus 1 14 chinensis 1 14 gecko gecko 5 14 japonicus 1 14 mindorensis 1 14 monarchus 1 14 palawanensis 1 14 palmatus 1 14 smithii 2 14 subpalmatus 1 14 swinhonis 1 14 vittatus 4 14 Gymnodactylus geckoides geckoides 2 14 Hemidactylus brookii brookii 4 14 brookii angulatus 2 14 brookii haitianus 10 14-15 (14.3) flaviviridis 2 14 frenatus 12 14 garnotii 2 14 giganteus 2 14 karenorum 2 14 leschenaultii 2 14-15 (14.5) 1967 KLUGE: GEKKONID LIZARDS 29 TABLE 1-(Continued)

No. of Eyeballs No.(Rangeof Scleraland Mean)Ossicles persicus 2 14 turcicus turcicus 2 14-15 (14.5) Hemiphyllodactylus typus typus 8 14-16 (14.8) yunnanensis 5 14 Heteronotia binoei 20 14-15 (14.1) spelea 2 14-15 (14.5) Homonota darwinii 4 13-14 (13.8) gaudichaudii 4 13-14 (13.5) horrida 10 14 Homopholis fasciata subsp. 2 14 wahlbergii 2 14 Lepidodactylus brevipes 2 14 guppyi 3 14-15 (14.3) listeri 1 14 lugubris 10 14-16 (14.3) manni 14 naujanensis 1 14 oorti 1 14 planicaudus 1 14 pumilus 5 14 shebae 2 14 woodfordi 2 14 Luperosaurus joloensis 1 14 macgregori 1 14 Lygodactylus capensis 4 14 conraui 2 14 picturatus picturatus 2 14 Microgecko helenae 4 14 Millotisaurus mirabilis 3 14 Narudasia festiva 3 14 Pachydactylus bibronii bibronji 5 14 capensis capensis 2 14 geitje 2 14 Palmatogecko rangei 4 14 Paragehyra petiti 1 14b Perochirus guentheri 4 14 Phelsuma barbouri 2 14 cepediana 4 13-14 (13.8) 30 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 TABLE 1-(Continued) No. of Scleral Ossicles No. of Eyeballs (Range and Mean) laticauda 2 14 lineata subsp. 2 14 madagascariensis kochi 2 14 Phyllodactylus guentheri 2 14 homolepidurus homolepidurus 3 14-15 (14.3) inexpectatus 1 14 julieni 2 14 lanei subsp. 2 14 marmoratus 20 13-15 (13.9) palmatus 1 14 peringueyi 1 15 porphyreus porphyreus 2 14 tuberculosus tuberculosus 4 14 unctus 2 14 wolterstorffli 1 14 xanti nocticolus 2 14 Phyllopezus pollicaris poflicaris 3 14 pollicaris przewalskii 4 14-15 (14.2) Pristurus carteri collaris 2 14 crucifer 4 14 flavipunctatus flavipunctatus 6 14-16 (14.5) sokotranus 2 14 Pseudogekko compressicorpus 1 14 smaragdinus 1 14 Ptenopus garrulus 2 15-17 (16.0) Ptychozoon kuhli 2 14 Plyodactylus hasselquistii hasselquistii 2 14 hasselquistii ourdii 2 14 Quedenfeldtia trachyblepharus 8 14 Rhoptropella ocellata 2 13-14 (13.5) Rhoptropus afer 2 14 bradfieldi bradfieldi 2 14-15 (14.5) Saurodactylus fasciatus 4 14 mauritanicus brosseti 8 14 Tarentola americana 2 14 annularis 2 14 mauritanica mauritanica 5 14 neglecta 2 14 Teratolepis albofasciata 6 14 fasciata 15 13-14 (13.9) 1967 KLUGE: GEKKONID LIZARDS 31 TABLE 1-(Continued) No. of Scleral Ossicles No. of Eyeballs (Range and Mean) Thecadactylus rapicauda 2 14 Trachydactylus jolensis 1 14b Tropiocolotes tripolitanus algericus 2 14 Uroplatus fimbriatus fimbriatus 2 15 Gekkoninae (Group II) Stenodactylus arabicus 1 20 doriae 2 27-28 (27.5) grandiceps 1 24 khobarensis 1 28 major 1 26 petrii 3 20-22 (21.0) pulcher 1 24 slevini 1 26 sthenodactylus sthenodactylus 12 22-26 (24.0) sthenodactylus mauritanicus 2 26-27 (26.5) Teratoscincus microlepis 8 17-21 (19.4) scincus 7 15-16 (15.3) Sphaerodactylinae Coleodactylus amazonicus 4 12-14 (13.5) Gonatodes albogularis albogularis 4 14 albogularis fuscus 4 14 albogularis notatus 2 14 antillensis 2 14 atricucullaris 6 14-15 (14.3) humeralis 2 13-14 (13.5) vittatus vittatus 4 14 Lepidoblepharis microlepis 4 13-14 (13.8) Pseudogonatodes barbouri 2 14 Sphaerodactylus argus henriquesi 6 14 cinereus 4 14 difficilis 4 14-15 (14.3) goniorhynchus 3 14 inaguae 4 14 macrolepis macrolepis 4 13-14 (13.5) mariguanae 2 14 mertensi 2 14 parkeri 2 14-15 (14.5) torrei 2 14-15 (14.5)

a Includes Coleonyx variegatus variegatus and Coleonyx variegatus sonoriensis. b Count approximate because of damaged eye. 32 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 found in both sexes of a species, although swung back by the final copulatory thrust of Wiedersheim (1876) reported them to be the male. These observations rule out the absent from females of Phyllodactylus euro- possible function ascribed to the sacs by paeus (present in males). Brongersma (1934) Noble and Bradley (1933). has since corrected Wiedersheim's error. It Cloacal bones are subcutaneous subcaudal appears that the sacs are, in general, much elements found in almost all Gekkonoidea larger in males than in females. Noble and and in the xantusiid lizard genus Xantusia. Bradley (1933) studied sections of these The problem of homology has not been con- peculiar structures and found no evidence of sidered for these two widely different groups glandular activity in the squamous epithe- of lizards. The bones are restricted to males in lium lining the invagination. However, M. A. the Gekkonoidea and are invariably found in Smith (1933) stated that he found definite close association with the cloacal sacs. There glandular cells in the wall of the sac but could is either one pair or there are two pairs of not find any secretion in living or preserved these elements; the innermost is consistently specimens. The question of glandular activity present and borders the anterior, and gen- in the cloacal sac is still unanswered. Noble erally the lateral, margins of the sac. It has and Bradley noted that the lining of the been suggested that the inner element aids in pocket is shed during the regular molting enlarging the aperature of the sac. The ab- process and that the loose skin within the sence of cloacal bones from females and the recess can be pulled out without any apparent negative response to sexual stimulation, with discomfort to the animal. From these obser- regard to the size of the orifice and depth of vations, the authors were led to the conclu- the comparatively smaller sacs, may indicate sion that the sac has no sensory function. that the sacs are without function in this sex. Noble and Bradley (1933) performed a few The outer pair of bones varies from small, simple experiments on the sacs of living simple, and platelike to large, elaborate (as in Tarentola which give some insight into their Palmatogecko), and strongly projecting be- possible function. Sexual excitement ap- yond the surface of the tail. These outer ele- peared to cause the orifice of the sac to in- ments when well developed definitely aid the crease in diameter and the over-all depth of males of some species in increasing the size of the sac to increase in length, producing a the cloaca of the female during copulation slight vacuum. Noble and Bradley inferred (Greenberg, 1943; Pope, 1956). from this change in shape that the sacs act as The presence of both cloacal sacs and as- stimulating organs that tend to quiet the fe- sociated bones appears to represent the primi- male during copulation. M. A. Smith's (1933) tive character-state in the Gekkonidae as in- conjecture that the sacs are homologous with ferred from their wide distribution within the the sex or scent gland of crocodiles and snakes family. The following observations strongly has not been supported by any embryological indicate that the loss of the cloacal bones is or experimental data. Greenberg's (1943) correlated with the loss of the closely associ- study on the social behavior of Coleonyx pro- ated sacs. vides the best evidence of their function. He Cloacal sacs are present in all of the Euble- stated that when the male rubs his cloacal pharinae and all of the Diplodactylinae. spur across the cloaca of the female, the sacs These invaginations are present in all gek- of the male do not touch the female. When konine genera except the following: Aristel- the spur becomes embedded in the cloaca of liger, Lygodactylus (variable?), Millotisaurus, the female, the sac on the same side becomes Narudasia, Pristurus, Quedenfeldtia, and Sau- obliterated by a folding of the skin, while the rodactylus. In addition, M. A. Smith (1933) sac on the other side everts and becomes stated that both Phyllodactylus riebeckii and swollen. Greenberg suggested that the ever- P. elisae lack sacs and bones. Ailuronyx and sion of this sac acts to relieve pressure on the Perochirus require re-examination before inactive hemipenis that remains swollen and their condition can be stated with certainty. sheathed. He further suggested that the other Postcloacal sacs are absent from all of the sac may provide freedom of rotation for the Sphaerodactylinae. expanded base of the spur when the latter is Two pairs of cloacal bones are present in all 1967 KLUGE: GEKKONID LIZARDS 33 of the Eublepharinae and one or two pairs in bone, see character j-J (Angular Bone). The all of the Diplodactylinae. One or two pairs of splenial is present in the Eublepharinae and bones are present in the Gekkoninae with the Diplodactylinae. It is absent from only two exception of the following genera: Aristelliger, gekkonine genera, Pristurus and Ptyodactylus, Lygodactylus (variable?), Millotisaurus, Na- and from all of the Sphaerodactylinae. The rudasia, Pristurus, Quedenfeldtia, and Sauro- loss of the splenial in Pristurus and Ptyo- dactylus. The following genera have not been dactylus probably occurred in parallel as in- examined: Ailuronyx, Chondrodactylus, Lup- ferred from their numerous morphological erosaurus, Ptenopus, Rhotropella, and Rhop- differences (compare the generic diagnoses tropus. The bones are absent from all Sphaero- given by Loveridge, 1947, pp. 71, 273, re- dactylinae. It is interesting to note that all spectively). The many similarities between the genera in the Gekkoninae that lack sacs Pristurus and the Sphaerodactylinae besides and bones are African (Madagascar included) the loss of the splenial, such as the (1) pres- in distribution with the exception of Aristel- ence of diurnal or shade activity, (2) presence liger (West Indies and mainland of Central of sexual dichromatism, (3) presence of round America). This correlation may indicate the pupil in life, (4) presence of an eyelid which is section of the Gekkoninae that gave rise to more or less distinctly formed by a circumor- the New World sphaerodactyline line. The bital ring of tissue, (5) presence of simple, absence of sacs and bones from the Gek- undilated digits, as in the more primitive konidae is considered as having occurred only sphaerodactyline Gonatodes, (6) small adult once, until evidence to the contrary is size, and (7) absence of preanal organs, may presented. indicate a close relationship. It is for this rea- son that the loss of the splenial in Pristurus j-J. ANGULAR BONE and the Sphaerodactylinae is not considered The lower jaw in primitive reptiles con- as having occurred in parallel (see table 2). sisted of the following seven elements (Romer, The most primitive lower-jaw condition in 1956): dentary, coronoid, splenial, angular, gekkonid lizards consists of the dentary, prearticular, articular, and surangular. In the articular-prearticular-surangular, unreduced generalized lower jaw of the lizard all these coronoid, splenial, and angular as exhibited elements are present, but the articular and by the Eublepharinae and Teratoscincus. The prearticular are frequently fused. In addition, most advanced condition is represented by the surangular may fuse with the articular- the Sphaerodactylinae in which only the prearticular complex, and the splenial and dentary, articular - prearticular-surangular, angular may be lost or fused to the remaining and coronoid persist, with the last element bones (fig. 6). being extremely reduced and in some species The dentary, coronoid, and articular- almost lost (fig. 6). prearticular-surangular complex are consis- tently present in gekkonid lizzards. The angu- I-L. FRONTAL BONE lar is present in the Eublepharinae in all The frontal is the long, prominent, dermal, species except Coleonyx brevis and C. cranial element that usually forms the dorsal variegatus. The angular is absent from the margin of the orbit. The descending lateral Diplodactylinae and Sphaerodactylinae. In processes of the frontal meet ventrally and the Gekkoninae, it is present only in Terato- surround the olfactory lobes of the forebrain scincus. The presence of the angular, the in- in the Gekkota. The frontal is almost invari- crease in scleral ossicle number, the absence ably single in the Ascalabota, with the excep- of a calcified postcranial endolymphatic ap- tion of the Xantusiidae. Some ardeosaurids paratus, if confirmed, and the single parietal exhibit the paired form as well, but that they (as exhibited by Teratoscincus microlepis) do so is apparently owing to the preadult de- may indicate that Teratoscincus evolved di- velopmental stage of the fossil material rectly from the eublepharine stock. (Hoffstetter, 1964). From the widespread oc- currence of the single type of frontal through- k-K. SPLENIAL BONE out the Ascalabota, particularly among the For introductory remarks on the splenial more primitive gekkos, it is believed to be the 34 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135

SURANGULAR FORAMEN POSTERIOR MYLOHYOID FORAMEN OST4ERIOR . SURANGULAR FORAMEN

ORDER OF EVOLUTIONARY CHANGE

1. ANGULAR - LOST 2. SPLENIAL - LOST 3. CORONOID - EXTREMELY REDUCED 4. ARTICULAR- SLIGHTLY REDUCED

5. SURANGULAR - UNMODIFIED 6. DENTARY- UNMODIFIED FIG. 6. Evolution of the lower jaw in the Gekkonidae. Lateral (above) and medial (below) views of the jaw of a hypothetical primitive gekko, with the bony elements and other points of reference indicated. The order of evolutionary change from primitive to advanced is indicated below the drawing. primitive character-state in the Gekkonidae. tionship to the other gekkonine genera that The frontal is single in all of the Euble- possess paired frontals (see characters h-H, pharinae, Diplodactylinae, and Sphaero- j-J, and r-R), and it seems likely that the dactylinae and in most of the Gekkoninae. condition has evolved at least twice within The following gekkonine genera exhibit paired that subfamily. The paired frontals found in frontals: Ailuronyx, Homopholis, Phelsuma, the Gekkoninae may be secondarily derived Rhoptropella, Saurodactylus, and Teratoscin- from the single form by arrested development cus (paired in T. scincus, fused in young and and the retention of the embryonic condition. adult T. microlepis). The single frontal found i'n a few species of Phelsuma was probably m-M. NASAL BONES derived from the paired state by an extensive The nasals are almost invariably moder- filling in of bony material with age. The con- ately large, paired, dermal elements cover- dition of the frontal in Blaesodactylus requires ing the dorsal surface of the nasal capsule in further study. Teratoscincus shows little rela- the Squamata. Paired nasals are considered 1967 KLUGE: GEKKONID LIZARDS 35 primitive in the Gekkonidae (fusion being after hatching. A single parietal is found in advanced), as is inferred from the paired con- almost all adult non-gekkonid lizards and is dition found in the ancestral ardeosaurids. considered the primitive lacertilian condition The nasals are paired in all of the Euble- (Romer, 1956). It seems likely that the single pharinae, Diplodactylinae, and Sphaero- parietal of the Ardeosauridae is directly an- dactylinae. They are also paired in all Gek- cestral to that condition found in primitive koninae with the exception of adults of the gekkonids. following genera: Ailuronyx, Afroedura, Blae- The following remarks concerning the state sodactylus, Cnemaspis (africana, boulengerii, of the parietal in gekkonid lizards apply only kandiana, nigridius, q. quatturoseriata, sia- to adults, unless otherwise noted. The parietal mensis, and wynadensis; all other species is single in the Eublepharinae and paired in listed in table 1 have paired nasals), Cyrto- all of the Diplodactylinae and Sphaerodacty- dactylus (p. pelagicus, serpensinsula and linae. It is paired in all gekkonine genera vankampeni; all other species listed in table 1 except Perochirus (only guentheri examined) have paired nasals), Ebenavia, Hemiphyllo- and possibly Pachydactylus b. bibronii; in the dactylus, Lepidodactylus, Lygodactylus, Pero- latter species the extensive cranial orna- chirus, Phelsuma, Phyllodactylus (guentheri, mentation probably obscures the suture. The marmorata, and p. porphyreus), Pseudogekko, parietals were found to be fused in the largest Microgecko, and Uroplatus. adults of the sphaerodactyline Gonatodes Although the number of forms with fused antillensis and the gekkonine Gehyra var- nasals in the Gekkoninae is large, the condi- iegata, G. pilbara (fide Mitchell, 1965), Ter- tion in most genera appears to be associated atoscincus microlepis, and some species of with what are believed to be at least two Phyllodactylus and Phelsuma. The fusion natural groups within the subfamily. Ailur- of the parietals in these forms appears to have onyx, Afroedura, Blaesodactylus, Ebenavia, been the result of the filling in of bony ma- Lygodactylus, Phelsuma, and Uroplatus form terial with age. one group of relatively closely related genera It seems that the paired condition of the restricted to the Ethiopian Region (with the parietals, found in the majority of gekkos, exception of Phelsuma andamanensis of the has been derived from the primitive fused Andaman Islands). The second group, con- gekkonid type represented by the Euble- sisting of Hemiphyllodactylus, Lepidodactylus, pharinae and the ancestral Ardeosauridae. Pseudogekko, and possibly Perochirus, may The paired condition may be a neotenic be related and are essentially restricted to the feature of the Gekkonidae (Stephenson, eastern Oriental and the Oceanic regions. The 1960). The single parietal of Perochirus is former two assemblages of genera, if natural considered to be a reversion to the primitive ones, seem to be unrelated and indicate that form and therefore is treated as a specialized fusion of the nasals has occurred in parallel at character-state in the Gekkoninae (see table least twice within the Gekkoninae. Cnemaspis, 2). Cyrtodactylus, Phyllodactylus, and Microgecko which also have fused nasals cannot be placed o-O. AMPHICOELOUS OR PROCOELOUS satisfactorily in either group at this time nor PRESACRAL VERTEBRAE do they form a very clearly defined assem- All Squamata have procoelous presacral blage of their own. The fact that Cnemaspis, vertebrae, with the exception of many gek- Cyrtodactylus, and Phyllodactylus are inter- konid lizards. The occurrence of both pro- specifically variable in this character sug- coely and amphicoely has been used by gests a case of multiple parallelism. Only for most herpetologists as a major systematic the convenience of coding are the four genera character within the Gekkonidae. Underwood treated as one group. (1954) stated that the amphicoelous condi- tion, found in most gekkos, was secondarily n-N. PARIETAL BONE derived from a procoelous type, although he In general, in the Squamata the parietal is was later dissuaded from this viewpoint initially paired, and during ontogeny it fuses (Underwood, 1955) by the discoveries of to form a single element, normally shortly supposedly definitive amphicoelous Triassic 36 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 lizards. It now appears that this group of Parker, 1926). The other sphaerodactyline Mesozoic reptiles (Kuehneosaurus Robin- genera, which are all procoelous, have prob- son, 1962) actually formed a separate radia- ably evolved from a Gonatodes-like ancestor. tion and were not directly ancestral to lizards Noble (1921) was the first to recognize this as Underwood and others were led to believe. morphogenetic sequence in the Sphaerodacty- I agree with Underwood (1954) and Romer linae. Noble's observations strongly support (1956) in considering procoely the primitive the view that procoely has developed secon- presacral vertebral form in lizards. The fact darily in the Sphaerodactylinae. that the Ardeosaurinae have procoelous vertebrae supports this thesis for gekkonid p-P*. HYOID ARCH lizards. I have not found the arguments pre- The reptilian hyoid apparatus is an ex- sented by Camp (1923) and Holder (1960) to tremely complex structure which was de- be of sufficient weight to consider amphicoely rived from the ancestral amphibian hyoid the primitive condition. arch and two posterior visceral arches. The All of the Eublepharinae are procoelous. apparatus lies in the floor of the mouth and In the Diplodactylinae typical amphicoely pharynx and is closely associated with the predominates except for the following genera: musculature of those regions. The apparatus Carphodactylus, Crenadactylus, Diplodactylus, functions in supporting and moving the Oedura, and Phyllurus. In these diplodacty- tongue and larynx. Three complete (un- line genera there is a tendency toward pro- broken) arches are considered the primitive coely; however, no specimen examined at- saurian condition (Romer, 1956). The hyoid tained the typical saurian form. All Gek- nomenclature used here follows that of Kluge koninae are amphicoelous with the single (1962). exception of Ebenavia which exhibits a typ- In the Eublepharinae, the hyoid cornu, the ical procoelous condition. In the Sphae- large, winglike projection at the hypohyal- rodactylinae only Gonatodes is amphicoel- ceratohyal union, is constant in shape and ous; all other genera are procoelous. similar to that shown for Coleonyx (Kluge, It appears that the primitive gekkonid 1962). Apparently the inner proximal cer- vertebral type was procoelous, as exhibited atohyal projection is absent from all genera. today by the Eublepharinae and derived The Diplodactylinae exhibit a large and vari- from the Jurassic Ardeosaurinae. On the ably shaped hyoid cornu. The inner proximal basis of the development of procoelous ver- ceratohyal projection was found in only the tebrae, as discussed by Romer (1956, p. 255) following genera: Carphodactylus, Naultinus, and Holder (1960, pp. 302-7), it seems Nephrurus, and Phyllurus. The gekkonine likely that the amphicoelous condition found hyoid cornu varies in shape and size and is in the majority of the gekkos could have been absent only from Tropiocolotes. The hypohyal- derived from the procoelous type by arrested ceratohyal union is very tenuous in the latter development and retention of the embryonic genus. The inner proximal ceratohyal projec- form. The tendency toward procoely, as tion is present in or absent from the Gek- exhibited by some diplodactyline genera, koninae. In the Sphaerodactylinae, the hyoid could have evolved secondarily by suppres- cornu is relatively large in Gonatodes and sion of the neotenic process, or it might sim- Lepidoblepharis, slightly less developed in ply be a reflection of the primitive genetic Sphaerodactylus, almost completely absent background of the subfamily. The gekkonine from Pseudogonatodes, and entirely lacking in genus Ebenavia probably followed the former Coleodactylus. The hypohyal-ceratohyal course. union is interrupted in the last-mentioned There appears to be little doubt that the genus. The hyoid arch of the gekkonine genus amphicoelous Gonatodes is the most primitive Tropiocolotes has gone slightly beyond the member of the Sphaerodactylinae; e.g., it evolutionarystate reached by Pseudogonatodes possesses (1) a large, unreduced coronoid, and approaches that of Coleodactylus (fig. 7). (2) a large squamosal, (3) a large, unreduced, The discontinuation of the hypohyal-cer- paroccipital process of the opisthotic, and atohyal union is almost certainly associated (4) a primitive type of digit (Noble, 1921; with the loss of the hyoid cornu. The evolu- 1967 KLUGE: GEKKONID LIZARDS 37

SECOND CERAT(

ORDER OF EVOLUTIONARY CHANGE

I I I plI

FIG. 7. Evolution of the branchial apparatus in the Gekkonidae. Ventral view of the primitive branchial apparatus of Coleonyx v. variegatus. The order of evolutionary change from primitive to advanced can be visualized from the schematic diagrams by following the course of the arrows (only the right side of the apparatus is shown). 38 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 tionary trend toward the loss of the hyoid is interrupted. The ends of the long cerato- cornu and the interruption of the hypohyal- branchial and epibranchial approach each ceratohyal union has probably been estab- other very closely (in one specimen of lished independently in the Gekkoninae and Sphaerodactylus parkeri they overlapped, and Sphaerodactylinae; the conditions in Tro- in one specimen of Gonatodes v. vittatus they piocolotes and Pseudogonatodes are treated as secondarily fused; apparently both specimens the same character-state but as having were abnormal). The second epibranchial is evolved in parallel. The inner proximal present in all genera except Coleodactylus. ceratohyal projection is present in Gonatodes, The loss of the epibranchial appears to be Lepidoblepharis, and Sphaerodactylus. The correlated with shortening and the ultimate loss of this projection in Pseudogonatodes and loss of the paroccipital process of the Coleodactylus appears to be associated with opisthotic in this genus, as well as in the the trend toward a discontinuous hyoid arch. gekkonine genus Pristurus (fig. 7). The loss It seems likely that the inner proximal pro- of the epibranchial in the most advanced jection of the ceratohyal has been lost in- sphaerodactyline genus Coleodactylus and in dependently in each of the four subfamilies. Pristurus is interpreted as having occurred It is also possible that this process has in parallel. evolved more than once within the Gek- The following evolutionary trends in the konidae. morphology of the hyoid apparatus of gek- konid lizards are readily perceived (fig. 7). q-Q****. SECOND VISCERAL ARCH Primitively, three complete arches were For introductory remarks on the hyoid present. Departures from the primitive con- apparatus, see character p-P* (Hyoid Arch). dition involve successive discontinuities in In the Eublepharinae, Coleonyx exhibits three the second visceral arch and then in the hyoid complete visceral arches which represent a arch. After the second visceral arch is inter- unique condition in modern lizards (Kluge, rupted, the ceratobranchial is frequently lost. 1962). The second visceral arch is separated The second epibranchial is usually retained; in all other eublepharine genera, but the however, it is reduced, and in some genera it ceratobranchial and epibranchial parts form is lost along with the reduction and ultimate an extensive secondary zone of unfused con- loss of the paroccipital process of the opistho- tact. The second visceral arch is invariably tic. discontinuous in the Diplodactylinae, and the long ceratobranchial and epibranchial parts r-R. SQUAMOSAL BONE are normally separated by moderate to large For introductory remarks on the squamosal distances, with the exception of Rhyn- bone, see character g-G (Supratemporal choedura. The ceratobranchial and epi- Bone). The squamosal is consistently present branchial overlap in the latter genus but do in all Eublepharinae and Diplodactylinae. In not come into contact. Stephenson and the Gekkoninae, the squamosal is absent only Stephenson (1956) stated that Naultinus had from Lygodactylus, Saurodactylus mauri- three complete arches. My material of this tanicus brosseti (although present in S. genus indicates an interruption in the second fasciatus), and Teratoscincus. The squamosal visceral arch. The ceratobranchial is moder- is present in all Sphaerodactylinae except ately long to very long in all diplodactyline Coleodactylus. genera. The second visceral arch appears to The loss of the squamosal appears to be be consistently broken in the Gekkoninae. correlated with the reduction of the paroc- The second ceratobranchial was completely cipital process of the opisthotic except in absent from 60 per cent of the genera ex- Teratoscincus. As the paroccipital process amined (the advanced condition), and in the shortens, and the squamosal is lost, the remaining 40 per cent it ranged from being quadrate moves medially under the cranial moderately long to being very long. The complex and eventually articulates with the second epibranchial was present in all genera prootic. In Teratoscincus the quadrate artic- with the exception of Pristurus. In all of the ulates loosely with the large paroccipital Sphaerodactylinae, the second visceral arch process. It appears that the squamosal has 1967 KLUGE: GEKKONID LIZARDS 39 been lost independently in the Gekkoninae Character h-H: Number of scleral ossicles per and the Sphaerodactylinae (i.e., Coleodactylus eyeball (2 character-states) is the most highly evolved sphaerodactyline h. Significantly more than 14 (primitive); and does not share any other diagnostic weight 1 features with more generalized Gekkoninae). H. Approximately 14 (advanced); weight 2 Character i-I: Cloacal sacs and bones (2 character- Within the Gekkoninae there is some mor- states) phological similarity between Lygodactylus i. Present (primitive); weight 1 and Saurodactylus; however, Teratoscincus I. Absent (advanced); weight 2 appears to be totally unrelated (see other Character j-J: Angular bone (2 character-states) character discussions). The loss of the squa- j. Present (primitive); weight 1 mosal within the Gekkoninae is therefore J. Absent (advanced); weight 2 inferred as having occurred in parallel (fig. 3). Character k-K: Splenial bone (2 character-states) k. Present (primitive); weight 1 EVOLUTION OF THE SUBFAMILIES K. Absent (advanced); weight 2 K. Absent (advanced-independent of K); The coding and weighting of the char- weight 2 acters discussed above are necessary prelim- Character l-L: Frontal bone (2 character-states) inaries to the delimitation of natural assem- 1. Single (primitive); weight 1 blages of genera by the method used here L. Paired (advanced); weight 2 and the calculation of advancement (diver- L. Paired (advanced-independent of L); gence) indexes for the recognized taxa (tables weight 2 2 and 3). The following list indicates the Character m-M: Nasal bones (2 character-states) letter symbols and number of character- m. Paired (primitive); weight 1 states of each character, the primitive or ad- M. Fused (advanced); weight 2 vanced condition of each state and its numer- M. Fused (advanced-independent of M and ical weight, and suggested parallelisms. M); weight 2 M. Fused (advanced-independent of M and Character a-A: True eyelids or spectacle (2 char- = M); weight 2 acter-states) Character n-N: Parietal bone (2 character-states) a. True eyelids present (primitive); weight 1 n. Single (primitive); weight 1 A. Spectacle present (advanced); weight 2 N. Paired (advanced); weight 2 Character b-B: Development of premaxillary n. Single (advanced-reversion to primitive bone (2 character-states) condition); weight 3 b. From two centers of ossification (primitive); Character o-O: Type of presacral vertebrae (2 weight 1 character-states) B. From one center of ossification (advanced); o. Procoelous (primitive); weight 1 weight 2 0. Amphicoelous (advanced); weight 2 Character c-C: Postcranial endolymphatic ap- o. Procoelous (advanced-reversion to primi- paratus (2 character-states) tive condition, independent of g); weight 3 c. Calcified sac absent (primitive); weight 1 o. Procoelous (advanced-reversion to primi- C. Calcified sac present (advanced); weight 2 tive condition, independent of oJ; weight 3 Character d-D: Distribution of escutcheon scales Character p-P*: Hyoid arch (3 character-states) (2 character-states) p. Hyoid cornu large, hypohyal-ceratohyal d. Absent (primitive); weight 1 union not tenuous (primitive); weight 1 D. Present (advanced); weight 2 P. Hyoid cornu small, hypohyal-ceratohyal Character e-E: Ability to vocalize (2 character- union tenuous (advanced); weight 2 states) P*. Hyoid cornu absent, hypohyal-ceratohyal e. Present (primitive); weight 1 union broken (more advanced than P); E. Absent (advanced); weight 2 weight 3 Character f-F: Number of eggs laid (2 character- P. Hyoid cornu small, hypohyal-ceratohyal states) union tenuous (advanced-independent of f. Two (primitive); weight 1 P); weight 2 F. One (advanced); weight 2 Character q-Q****: Second visceral arch (5 char- Character g-G: Supratemporal bone (2 character- acter-states) states) q. Ceratobranchial-epibranchial union con- g. Present (primitive); weight 1 tinuous (primitive); weight 1 G. Absent (advanced); weight 2 Q. Ceratobranchial-epibranchial union broken, 'I I I I I '-4w '. ' 9 -

'.4 *e * *

0 bzz 86~~ ~ ~

co --

44~~~~~~~~~~~~~~~~~~~~~~.

40 1967 KLUGE: GEKKONID LIZARDS 41 elements overlap and remain in close asso- scales absent; voice present; two eggs laid; ciation (advanced); weight 2 supratemporal present or absent; scleral Q*. Ceratobranchial-epibranchial union broken ossicles 13 to 25 (mean 16.7; average devi- and elements widely separated (more ad- ation of the means of the genera 2.7); cloacal vanced than Q); weight 3 bones present; Q**. Ceratobranchial lost, epibranchial present sacs and two pairs of cloacal (more advanced than Q*); weight 4 angular rarely absent; splenial present; Q***. Ceratobranchial present, epibranchial frontal single; nasals paired; parietal single; lost (more advanced than Q*-independent vertebrae procoelous; hyoid cornu present; of Q**); weight 4 inner proximal ceratohyal projection absent; Q****. Ceratobranchial lost, epibranchial lost second visceral arch continuous or inter- (more advanced than Q** and Q***); weight rupted; if second visceral arch is interrupted, 5 ceratobranchial and epibranchial forming Q. Ceratobranchial-epibranchial union broken, extensive zone of unfused contact; squamosal elements overlap and remain in close associ- present. ation (advanced-independent of Q); weight 2 RANGE: A discontinuous distribution; two Character r-R: Squamosal bone (2 character- genera restricted to the Oriental Region, two states) to the Ethiopian Region, and one to southern r. Present (primitive); weight 1 North America and Central America (map 1). R. Absent (advanced); weight 2 GENERA EXAMINED: A eluroscalabotes R. Absent (advanced-independent of R and Boulenger; Coleonyx Gray; Eublepharis Gray; B); weight 2 Hemitheconyx Stejneger; Holodactylus Boett- R. Absent (advanced-independent of R and ger. B:); weight 2 SUBFAMILY DIPLODACTYLINAE I have grouped the 82 genera that were examined in this study into four subfamilies DIAGNOSIS: True eyelids absent, spectacle (Eublepharinae, Diplodactylinae, Gekkon- present; premaxilla developing from two cen- inae, and Sphaerodactylinae) on the basis of ters of ossification, paired condition persisting the greatest number of shared or unshared in some adults; calcified endolymphatic sacs characters and least number of parallelisms in postcranial region absent; preanal organs (table 2; fig. 8). The use of these criteria generally present, escutcheon scales absent; with multiple characters, both internal and voice present; two eggs laid, or bearing living external, and the fact that the taxonomic young; supratemporal absent; scleral ossicles products are consistent with present zoogeo- 21 to 40 (mean 31.9; average deviation of the graphical concepts strongly suggest that the means of the genera 3.8); cloacal sacs and one recognized subfamilies are natural ones. The or two pairs of cloacal bones present; angular distribution of the character-states in each absent; splenial present; frontal single; subfamily (reduced from a generic table for nasals paired; parietal paired; vertebrae gen- the sake of brevity) is easily visualized when erally amphicoelous, some tendency toward table 2 is read horizontally; when table 2 is procoely; hyoid cornu present; inner proximal read vertically the evolutionary trend or ceratohyal projection rarely present; second trends of each character are indicated relative visceral arch interrupted; ceratobranchial to the taxa. The genera that compose the long, normally separated from epibranchial subfamilies are listed below, following an ex- by moderate to large distance; squamosal panded definition of the higher taxa and a present. brief description of their geographical range. RANGE: Restricted to Australia (excluding Tasmania), New Caledonia and the Loyalty SUBFAMILY EUBLEPHARINAE Islands, and New Zealand (map 1). DIAGNOSIS: True eyelids present, spectacle GENERA EXAMINED: Bavayia Roux; Car- absent; premaxilla developing from two cen- phodactylus Gunther; Crenadactylus Dixon ters of ossification, paired condition persist- and Kluge; Diplodactylus Gray; Eurydacty- ing in some adults; calcified endolymphatic lodes Wermuth; Heteropholis Fischer; Hop- sacs in postcranial region absent; preanal lodactylus Fitzinger; Naultinus Gray; Ne- organs almost invariably present, escutcheon phrurus Gunther; Oedura Gray; Phyllurus 42 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 Schinz; Pseudothecadactylus Brongersma; enger; Lepidodactylus Fitzinger; Lupero- Rhacodactylus Fitzinger; Rhynchoedura Gun- saurus Gray; Lygodactylus Gray; Microgecko ther. Nikolsky; Millotisaurus Pasteur; Naruda- sia Methuen and Hewitt; Pachydactylus SUBFAMILY GEKKONINAE Wiegmann; Palmatogecko Anderson; Para- DIAGNOSIS: True eyelids absent, spectacle gehyra Angel; Perochirus Boulenger; Phel- present; premaxilla developing from single suma Gray; Phyllodactylus Gray; Phyllopezus center of ossification, paired condition absent Peters; Pristurus Ruppell; Pseudogekko Tay- from adults; calcified endolymphatic sacs lor; Ptenopus Gray; Ptychozoon Kuhl; Pty- present in postcranial region; preanal organs odactylus Goldfuss; Quedenfeldtia Boettger; either present or absent, escutcheon scales Rhoptropella Hewitt; Rhoptropus Peters; absent; voice present; two eggs laid; supra- Saurodactylus Fitzinger; Stenodactylus Fitz- temporal absent; scleral ossicles in Group I 13 inger; Tarentola Gray; Teratolepis Gunther; to 17 (mean 14.0; average deviation of the Teratoscincus Strauch; Thecadactylus Gold- means of the genera 0.2), in Group II 15 fuss; Trachydactylus Haas and Battersby; to 28 (mean 21.7; average deviation of Tropiocolotes Peters; Uroplatus Dumeril. the means of the genera 3.4); cloacal sacs and bones (either one or two pairs) variable, SUBFAMILY SPHAERODACTYLINAE present in 86 per cent, absent from 14 per DIAGNOSIS: True eyelids absent, spectacle cent; angular almost invariably absent; sple- present; premaxilla developing from single nial rarely absent; frontal variable, single in center of ossification, paired condition absent 87 per cent, paired in 13 per cent; nasals vari- from adults; calcified endolymphatic sacs able, paired in 72 per cent, single in 28 per present in postcranial region; preanal organs cent; parietal paired (single exception); verte- absent, escutcheon scales present; voice ab- brae amphicoelous (single exception); hyoid sent; single egg laid; supratemporal absent; cornu almost invariably present; inner proxi- scleral ossicles 12 to 15 (mean 14.0; average mal ceratohyal projection either present or deviation of the means of the genera 0.1); absent; second visceral arch interrupted; cloacal sacs and bones absent; angular absent; ceratobranchial variably present in 40 per splenial absent; frontal single; nasals paired; cent, absent from 60 per cent; ceratobran- vertebrae generally procoelous; hyoid cornu chial, if present, separated from epibranchial variable, rarely absent; hyoid arch almost in- by moderate to large distance; epibranchial variably continuous; inner proximal cerato- present (single exception); squamosal rarely hyal projection variable, eithber present or absent. absent; second visceral arch interrupted; RANGE: Circumglobal; New World be- ceratobranchial long, normally separated tween latitude 480 S. and latitude 350 N.; from epibranchial by small distance; second Old World between latitude 40° S. and lat- epibranchial rarely absent; squamosal rarely itude 500 N. (map 1). Found on all major land absent. masses and almost all oceanic islands. RANGE: Confined to New World tropics, GENERA EXAMINED: Afroedura Loveridge; between latitude 220 S. and latitude 260 N. Agamura Blanford; Ailuronyx Fitzinger; Al- Known from both the Cocos and Galapagos sophylax Fitzinger; Aristelliger Cope; Blaes- Islands in the Pacific and generally present odactylus Boettger; Bogertia Loveridge; Briba throughout the West Indies (map 1). Amaral; Bunopus Blanford; Calodactylodes GENERA EXAMINED: Coleodactylus Parker; Strand; Chondrodactylus Peters; Cnemaspis Gonatodes Fitzinger; Lepidoblepharis Peracca; Strauch; Colopus Peters; Cosymbotus Fitz- Pseudogonatodes Ruthven; Sphaerodactylus inger; Crossobamon Boettger; Cyrtodactylus Wagler. Gray; Dravidogecko Smith; Ebenavia Boett- In table 3, the numerical values that indi- ger; Geckolepis Grandidier; Geckonia Moc- cate the primitive or advanced states replace quard; Gehyra Gray; Gekko Laurenti; Gym- letter symbols. The relative degree of diver- nodactylus Spix; Hemidactylus Oken; gence (advancement index) for each family Hemiphyllodactylus Bleeker; Heteronotia Wer- is the total of their numerical values (last muth; Homonota Gray; Homopholis Boul- column, table 3). Fractions of whole numbers % 0 0 0%~~~~~~~~~~0

U) %0C40 I- 0 0 000 0

0 0 0 0 * 0 0 ~~~~4 0% 00 U)~~C 00 0 *eq %0 - ~~~~~~~~ ~ ~#)% -NO0 I 0- 0 eq -~~~~~~eq0K ~~~

* 00 000 z ~~~~~0% 0 4 % co5 .

o %~~~~~~~~~~~~~~~0%0 0

u 1 ~ ~ ~ o

eq U) U)~~~~e

t6.-

5000~~~~

4.1~~~ ~ ~~~~~~~4c

43 44 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135

FIG. 8. Phylogeny of the Gekkonidae expressed in the form of a dendrogram which is superimposed on a background of advancement indexes. Open circles indicate the presently recognized subfamilies, Eublepharinae, Diplodactylinae, Gekkoninae, and Sphaerodactylinae; closed circles suggest hypothetical intermediate taxa. Numbers refer to degrees of advancement from the primitive number based, on 18 characters. The letters (a to m) correspond to the characters as they are coded on pages 39-41. Once the character-state changes (e.g., from a to A, or from g to g-G), the reader can assume that all derived taxa (hypothetical or extant) also exhibit that state. were used in cases in which there was more be of equal taxonomic rank (subfamilies) than one character-state within a taxon. The because of the nearly uniform increase in the fractions were determined by dividing the total advancement index from group to group numerical value by the percentage of the (table 3): advancement index, 5.57 between total number of genera examined (and species the Eublepharinae and Diplodactylinae, 4.38 if intragenerically variable) that exhibited between the Diplodactylinae and Gekkoninae, that particular state. and 4.69 between the Gekkoninae and The phylogenetic relationships are ex- Sphaerodactylinae. pressed in the form of a dendrogram (fig. 8) which is superimposed on a background of ZOOGEOGRAPHICAL HISTORY advancement indexes similar to that used by OF THE SUBFAMILIES W. H. Wagner, Jr., and his students at the I can comment on the fundamental zoo- University of Michigan (Hardin, 1957; geographical features of the Gekkonidae, Wagner, 1961; Scora, 1966; see Lellinger, using as a basis for the discussion our knowl- MS, for critical review of the method). Those edge of the present geographical distribution characters that exhibit intersubfamilial paral- of the subfamilies, their proposed relation- lelisms (n-N to r-R; table 2) were not used in ships, and their probable course of evolution the construction of the dendrogram, but the (maps 1, 2; fig. 8). A general understanding of numerical values for all 18 characters (table the zoogeography of the family is a necessary 3) were employed in determining the ad- preliminary to more detailed studies on the vancement index of each subfamily. subfamilies which are in preparation. The generic assemblages are considered to The Gekkonidae almost certainly evolved 1967 KLUGE: GEKKONID LIZARDS 45 from the basic Gekkota stock some time in distribution of the allopatric species of the Mesozoic, probably during Upper Juras- Eublepharis (see following discussion for sic-Lower Cretaceous. Jurassic-Cretaceous details) and the fact that this genus appears age seems appropriate on the basis of the to be more closely related to Aeluroscalabotes relationships of the Gekkonidae to the neo- than does any other (see individual discus- Jurassic Ardeosauridae and the time prob- sions of subfamilial diagnostic characters) ably required for the Gekkonidae to have also suggest southeast Asia as the center of reached the morphological stage of evolution early gekkonid evolution. exhibited by the early and middle Tertiary Additional support for southeast Asia as a fossils known from France, Morocco, and the place of origin of gekkonid lizards can be United States (Hoffstetter, 1946, 1961; Estes, taken from the Diplodactylinae. This rel- 1963). atively primitive subfamily is restricted to The circumglobal disjunct distribution of the Australian Region (Kluge, MS). The fact the Eublepharinae (all genera are allopatric; that the most likely course of entry into the map 1) and the large number of primitive region was via the Indo-Australian archipel- characters retained by this subfamily (see ago and the rather well-established relation- tables 2 and 3; the divergence index is ships with the Eublepharinae also indicate only 1.36 from the hypothetical primitive southeast Asia as the place of origin for the form on the basis of 18 characters) suggest family. that it is represented today by a group of The possibility of an eastward dispersal of primitive relict genera. The genus Aeluro- the Eublepharinae in the direction of the scalabotes is restricted to Malaya, southern Australian land mass by way of the Indo- Thailand, Sumatra, Borneo, and the Soela Australianarchipelagoisstrongly suggestedby Islands (probably Sanana). It is very distinct the geographical proximity of Aeluroscal- morphologically from all related genera, and, abotes to that region (a subspecies, A. dorsalis on the basis of the following skeletal fea- multituberculatus, is known from the Soela tures, it appears to be the most primitive Islands, probably Sanana, only 350 miles genus in the subfamily and therefore in the west of New Guinea). If the Eublepharinae entire family: the splenial and angular in the migrated to the New Guinea-Australian land lower jaw and the squamosal and supra- mass (Termier and Termier, 1952), possibly temporal in the temporal region are invari- they were replaced by the major diplodacty- ably present, and the scleral ossicle number is line radiation that centered in that region in the mid-twenties (23 to 25). The mas- (Kluge, MS). siveness of the platelike interclavicle and The arboreal habit of the straight-toed clavicles, which are almost invariably imper- Aeluroscalabotes, in contrast to its straight- forate, also strongly suggests a primitive form toed terrestrial subfamilial counterparts, can (Camp, 1923, pp. 366-369). Almost without be interpreted either as a specialization or as exception, Aeluroscalabotes has been found at a vestige of the primitive gekkonid mode of night in tropical forests on vegetation (from life. The digits of Aeluroscalabotes are short, ground level to 10 feet high) usually associ- straight, and thick and do not appear to be ated with watercourses (Taylor, 1963; Robert supplied with specialized microscopic cling- F. Inger and F. Wayne King, personal com- ing structures. The only digital feature that munications). All other genera in this primi- might be associated with arboreal life is the tive subfamily inhabit more arid areas and nearly zygodactylous position of the digits therefore more recently evolved floral hab- and the enlarged palmar scales (Rooij, 1915, itats, because the early period of gekkonid p. 27, fig. 16). The body of Aeluroscalabotes evolution took place in association with the is long and relatively slender, and the tail is Late Mesozoic and Tropical Tertiary Geo- prehensile (F. Wayne King, personal com- floras (Axelrod, 1959, 1960). From the above munication), as is typical of many arboreal evidence it appears that southeast Asia may lizards, but the limbs are relatively short and have been the place of origin and early evolu- stout (round in cross section) and do not ap- tion of the Eublepharinae and possibly of all pear to be well suited for climbing, partic- gekkonid lizards. The- peculiar geographical ularly in tropical vegetation. Their slow, 46 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 deliberate movements are similar to those of juvenile color pattern, and many skeletal fea- chameleons. The contrasting arboreal and tures (Kluge, 1962), the southern group of non-arboreal features of Aeluroscalabotes may species appears to be more closely related to be indicative of the generalized (primitive) the present-day Eublepharis (particularly condition of the family. macularius and hardwickii) than do any of the The genus Eublepharis appears to be much species of the northern group which are con- more closely related to Aeluroscalabotes than siderably closer geographically to the pro- do the other eublepharine genera (see indi- posed route of entry into the New World. vidual discussions of the subfamilial diag- The southern group occurs in what is believed nostic characters, and Kluge, 1962) and prob- to be a derivative of the ancestral tropical ably evolved from an Aeluroscalabotes-like flora of the New World in which the genus stock in southeast Asia. This phase of evolved. The much more highly evolved eublepharine evolution probably occurred in northern group of species occupies primarily the late Cretaceous, but convincing evidence the North American deserts which geolog- in support of this point of view is lacking for ically and floristically have had a relatively the most part. As discussed below, the early recent and varied evolution (Axelrod, 1958). Tertiary dispersal of a Coleonyx-like form to These facts may explain the marked differ- the New World necessitates a pre-Tertiary ences between the two species groups in origin of Eublepharis. Doubtless, the ances- morphologic divergence from the primitive tral Eublepharis had a much wider geograph- form and the degree of subspecific differentia- ical range in the past, as can be inferred from tion (Klauber, 1945). the present-day disjunct distribution of the An interesting point arises from a consid- genus (southwestern Asia, Norway Islands, eration of the development of the desert Gulf of Tongkin, Hainan, and the Riu Kiu habitat preference of the northern species Islands). From the widespread ancestral group in Coleonyx and of the Old World gen- Eublepharis group it appears that there were era that belong to the subfamily. The Sonora, at least two separate lines of evolution: (1) a Mojave, Chihuahua, and other associated New World group, now represented by deserts arose during the expansion of a re- Coleonyx, and (2) an African radiation rep- gional dry climate following the Eocene resented by two genera, Holodactylus and (Axelrod, 1960). With most of the deserts of Hemitheconyx. The single New World euble- the Old World, the Sahara, Pakistan, and pharine genus Coleonyx almost certainly Indian, also developing at this time, it must originated from a Eublepharis-like ancestor be assumed that multiple parallelism in hab- (Kluge, 1962) and probably arrived in North itat preference evolved in all the genera of the America by way of the Bering land bridge Eublepharinae, with the exception of the through the continuous Paleocene Sub- primitive forest type, Aeluroscalabotes. It ap- tropical floral belt (Axelrod, 1952, 1958). The pears that the ancestral stock of the northern present distribution of Coleonyx (Klauber, species group of Coleonyx was present in the 1945) suggests that the genus did not enter pre-desert habitat and, as deserts became South America. This interpretation is con- available, the various groups as we know sistent with the fact that North and South them today moved into arid regions (Axelrod, America were isolated by seaways of varying 1950). The occurrence of some of the more breadth throughout almost all of the Tertiary primitive forms of the northern species group (Simpson, 1953). Coleonyx is represented (C. variegatus abbotti and C. v. peninsularis; today by two very different groups of species Klauber, 1945) in chaparral and subtropical (Kluge, 1962): (1) a northern group consist- scrub may be indicative of the pre-desert ing of variegatus (including fasciatus) and habitat of the ancestral stock of the northern brevis, and (2) a southern group consisting of group (Savage, 1960). mitratus and elegans (the placement of re- The two African genera (Holodactylus and ticulatus, known only from a single specimen, Hemitheconyx) are morphologically very dif- in either group remains problematical until ferent from each other and probably did not additional material can be studied). On the evolve in situ from an ancestral form by sim- basis of the similar heterogeneous scalation, ple geographical splitting. The magnitude of 1967 KLUGE: GEKKONID LIZARDS 47 the morphological differences seems to sug- ago (map 2). Glaessner (1962) postulated gest two independent and temporally well- that during the Upper Cretaceous (more pre- spaced lines of evolution from the wide-rang- cisely at the end of the Maestrichtian stage) ing Eublepharis ancestor of southern Asia. a "wide-open" land connection existed be- This thesis is best exemplified by the distri- tween Australia and southeast Asia. He bution of the supratemporal among the three stated that extensive, long-term, land con- genera: present in Holodactylus and Euble- nections between these two areas existed only pharis macularius and E. kuroiwae orientalis, at the end of the Cretaceous. If the Dip- absent from Hemitheconyx and E. hardwickii. lodactylinae migrated toward Australia over The absence of the Eublepharinae from the this particular land bridge at this time, it more arid parts of southern Africa today may follows that the subfamily must have orig- be due to replacement by the major gek- inated in southeast Asia at an earlier time in konine radiation that centered in that region the Mesozoic. This thesis is in accord with the (Loveridge, 1947). Another explanation time and place postulated for the evolution might be that both African eublepharine of the family. It is important to note that the genera evolved in the xeric environment of Upper Cretaceous has also been recognized as the lower-middle latitude of the Northern the epoch in which the proto-Australian mar- Hemisphere (map 1), which began to de- supial stock migrated into the region by way velop in the early Tertiary, and that they of the Indo-Australian land bridge (David, have been unable to cross the more mesic 1950; Glaessner, 1962; Simpson, 1961). equatorial tropics into the Southern Hemi- It is generally accepted that following the sphere. Mesozoic, during the Paleocene (map 2), the The theory of continental drift is not con- sea inundated the land, and a major water sidered germane to a discussion of the zoo- barrier was formed between southeast Asia geography of the Gekkonidae, particularly and Australia (Termier and Termier, 1952). the Diplodactylinae. Fairbridge (1953) has It has been suggested by Burbidge (1960) shown in his studies on the Sahul Shelf (map that floral and faunal migrational advances 2) that the Wegenerian hypothesis of the from southeast Asia to Australia over this drifting northward of Australia during the water barrier might have been permitted in Mesozoic and Tertiary is geologically unten- the early Tertiary by way of "insular step- able. Glaessner (1962) stated that New ping stones." The Sahul Shelf (map 2) may Guinea has maintained its position relative to have been exposed completely or in part at Australia since the Jurassic. On the basis of different times during this period, and it faunal and floral evidence, Irving (1958), seems likely that it would at least have re- Burbidge (1960), Fleming (1962), and others duced the effect of the ocean as a barrier to have cast considerable doubt on the possi- migration. The possibility that the dip- bility of continental movement in the Aus- lodactyline ancestor migrated to the Aus- tralian Region during the Mesozoic and Ter- tralian Region during the early Tertiary by tiary. "island hopping," as Simpson (1961) pro- It appears that the Diplodactylinae posed for marsupials, should not be totally evolved from the primitive gekkonid stock discounted in view of the well-known rafting in the tropics of southeast Asia some time abilities of modern gekkonines (McCann, during the late Mesozoic. The modern Dip- 1953, 1955; Brown and Alcala, 1957). This lodactylinae are restricted to the Australian time is, however, somewhat in conflict with Region (Australia, New Caledonia, Loyalty the early and middle Tertiary periods pos- Islands, and New Zealand; see map 1) and do tulated for the evolution and dispersal of the not appear to have radiated outside this bio- subfamily (see previous discussion, and geographic area (Darlington, 1957). It ap- Kluge, MS). pears that the ancestral diplodactyline stock, The proposed route by which the dip- following its probable origin in southeast lodactyline ancestor moved into the region Asia from a eublepharine ancestor, dispersed of Australia coincides with the Sumatran in the direction of Australia through the gen- Migration Tract postulated by van Steenis eral region of the Indo-Australian archipel- (1934a, 1934b, 1936) on the basis of his lIN74 z

48 1967 KLUGE: GEKKONID LIZARDS 49 studies on the primitive, tropical, montane of genera, primarily African in distribution. Malaysian flora (map 2). David (1950), con- As an indicator of relationships, Taylor and sidering isolation and all related events, hy- Leonard (1956) stressed the importance of pothesized that the autochthonous Australian the lack of preanal pores in all the endemic fauna developed during the Tertiary. The gekkonine genera of the New World. These Diplodactylinae are believed to be a prime authors apparently overlooked the fact that example of the autochthonous fauna of this preanal pores are present in the genus Briba region. (Amaral, 1935). In any event, the erratic By Upper Eocene time and continuing on distribution of preanal pores in the Gek- into the Pliocene the sea surrounded Aus- koninae precludes the use of that character tralia and covered most of New Guinea with alone as an indicator of relationships. It the exception of its southernmost part seems likely that the New World gekkonine (David, 1950; Glaessner, 1962). The Wes- genera were in most cases independently de- tralian (and associated Timor-East Celebes), rived from Old World ancestors. Occasional Tasman, and Papuan geosynclines appear to trans-Atlantic rafting for gekkos does not have formed the major seaways isolating seem improbable in view of the favorable this region during the Tertiary. It is postu- surface currents and winds (Darlington, lated that the diplodactyline stock was res- 1957) and the time available for the forma- ident in the Australian Region (inclusive of tion of the rather limited New World fauna Australia and New Guinea) by at least (McCann, 1953; Brown and Alcala, 1957; Paleocene-Eocene time (map 2). King, 1962). The present distribution of Tar- Concurrent, or nearly so, with the origin entola (one species in the West Indies and 10 of the Diplodactylinae from a southeast species and subspecies in southern Europe Asian eublepharine ancestor and movement and northern Africa, including the Canary in the direction of the Indo-Australian arch- Islands) is almost certainly a result of trans- ipelago, the Gekkoninae probably dispersed Atlantic rafting. Late Pleistocene material westward through southwestern Asia toward of the species T. americana of the West Indies Africa. There is a moderately large number of substantiates its presence in the New World gekkonine genera in Africa and Madagascar before the arrival of European man and in southwestern Asia that exhibit a few (Etheridge, 1956b; also see Koopman and morphological similarities, such as fused nasals Ruibal, 1955). Hemidactylus brooki is very and paired frontals (see individual discussions widely distributed in Africa and throughout of subfamilial diagnostic characters), and ap- the Greater Antilles and Colombia (=H. pear to be relatively closely related. Terato- leightoni) in the New World. Its distribution scincus (and possibly Stenodactylus) almost in the New World does not appear to be as- certainly formed another evolutionary line sociated with human activities, unlike that on the basis of the increased ossicle num- of the South American and Lesser Antillean ber and presence of an angular in the lower H. mabouia. Another Hemidactylus species jaw. Possibly these groups of genera represent (undescribed) from northwestern South concentrated remnants of the earliest gek- America and a Lygodactylus species (also un- konine radiations. The Oriental, Oceanic, and described) from Brazil may represent some- Australian regions support only "modern ex- what older, independent colonizations from panding dominants" (Underwood, 1957), their Old World congeners. such as Gehyra, Cyrtodactylus, Lepidodactylus, Superimposed both geographically and and Gekko, and more primitive forms do not temporally on the earliest Old World gek- appear to have evolved in the eastern Paleo- konine radiations are a large series of genera tropical areas. that I consider to be recent expanding dom- On the basis of their extreme morphological inants (e.g., Gekko, Gehyra, Hemidactylus, differences, the endemic gekkonine genera of Lepidodactylus, Cyrtodactylus, and Cnem- the New World do not appear to form a nat- aspis). The degree of speciation, the distri- ural group (Kluge, 1964). With few excep- butional patterns, and the morphological tions, each New World genus can be shown specializations of these genera indicate their to be related to an Old World genus, or group recent dominance and to some degree their so BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 close relationship. There are still many gek- on the basis of the common loss of cloacal konine genera that do not appear to be rep- sacs and bones and diurnal habits. It is pos- resentative of either the early or the more sible that the ancestral sphaerodactyline modern radiations. These genera are prob- stock arrived in the New World tropics at an ably remnants of minor splinter groups that early time (probably early Tertiary), by evolved for the most part from separate trans-Atlantic rafting. The strong African stocks of the earlier gekkonine radiations. affinities certainly do not support a concept The Sphaerodactylinae are represented of a migration into the New World via the today by a morphologically and behaviorly Bering land bridge. The dominance of the well-circumscribed series of genera that are Sphaerodactylinae in the New World is pos- primarily restricted to the Neotropical sibly correlated with the absence of a major Region (map 1). The ancestral sphaerodacty- gekkonine radiation. The large number of line doubtless was derived from a gekkonine species of Sphaerodactylus and Gonatodes dem- stock (tables 2 and 3; fig 8), possibly near the onstrates the success of the subfamily in this African Lygodactylus and its relatives (sensu region. lato). This relationship is suggested primarily SUMMARY THE LIZARD FAMILY Gekkonidae consists of (o) presacral vertebrae procoelous or am- 82 genera and approximately 650 species. phicoelous, (p) morphology of the hyoid arch, The family is found on the majority of land (q) morphology of the second visceral arch, masses between latitude 500 N. and lati- and (r) squamosal bone present or absent. tude 500 S. and has adapted to most environ- The number of character-states of each of mental extremes therein. Important aspects the 18 diagnostic characters is discussed, and of the general biology of these lizards are the primitive or advanced condition of each summarized for the first time. The relation- state and their numerical weights are given. ships of the Gekkonidae to other modern liz- Possible parallelisms are also indicated. On ards are briefly discussed, and the family is the basis of the greatest number of shared or characterized in detail on the basis of inter- unshared characters and least number of nal and external morphology. It is suggested parallelisms, the 82 recognized genera are that the limbless lizards of the family Py- grouped into four subfamilies: the Euble- gopodidae evolved directly from the Gek- pharinae, the Sphaerodactylinae, the Dip- konidae. The fossil history of gekkonoids is lodactylinae, and the Gekkoninae. The last reviewed, and it appears that the extinct two subfamilies bear little resemblance to Upper Jurassic family Ardeosauridae is di- the taxa of the most recently proposed classi- rectly ancestral to gekkos. The Ardeosaurinae fication in terms of generic composition. The and the eublepharine gekkos have many relationships of the four subfamilies are ex- characters in common. The Tertiary fossil pressed in the form of a phyletic dendrogram gekkos Rhodanogekko, Caudurcogekko, and which is superimposed on a background of Gerandogekko appear to be more closely re- advancement indexes (extrapolated from the lated to the Gekkoninae than to the other numerical weighting of the character-states). subfamilies as they are defined herein. These The Diplodactylinae appear to have been fossil genera and the Ardeosauridae are very derived directly from the most primitive sub- similar to modern gekkos, which suggests an family, the Eublepharinae, whereas the Gek- Upper Jurassic-Lower Cretaceous origin of koninae probably evolved from a consider- the Gekkonidae. ably more advanced form. The gekkonid The most recently proposed classification subfamily Sphaerodactylinae is the most ad- of gekkonid lizards, based on the shape of the vanced, and it appears to have been derived pupil, does not appear to be a natural one from the evolutionary stock that gave rise to because of the variability of the diagnostic the Gekkoninae. The four generic assem- character. A new subfamilial classification blages are considered to be of equal taxo- is proposed on the basis of an examination of nomic rank (subfamilies), unlike that pro- the morphology of all 82 recognized genera, posed in the most recent classification, and 283 species and subspecies, represented because of the nearly uniform increase in by nearly 1000 specimens. The following the total advancement index from group to characters are used in the diagnoses: (a) true group. eyelids or spectacle present, (b) premaxillary The four taxonomic products are consistent bone developing from one or two centers of with presently recognized zoogeographical ossification, (c) calcified postcranial endo- concepts. It appears that southeastern Asia lymphatic sacs present or absent, (d) preanal was the place of origin and early evolution organs or escutcheon scales present, (e) abil- of the circumglobal, now largely allopatric, ity to vocalize present or absent, (f) number Eublepharinae, and possibly all gekkonid of eggs laid, two or one, (g) supratemporal lizards, some time during the Upper Jurassic- bone present or absent, (h) number of scleral Lower Cretaceous. The eublepharine genus ossicles, (i) cloacal bones and sacs present or Aeluroscalabotes is restricted to this general absent, (j) angular bone present or absent, region and appears to be the most primitive (k) splenial bone present or absent, (1) frontal living genus of gekkos. Eublepharis is con- bone paired or single, (m) nasal bones paired sidered to be the closest living relative of or fused, (n) parietal bones paired or fused, Aeluroscalabotes. From the ancestral Euble- 51 52 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 pharis stock there appear to have been two Gekkoninae evolved and dispersed westward separate lines of evolution within the sub- through southwestern Asia toward Africa. family: (1) a New World stock leading to The Gekkoninae are clearly the dominant Coleonyx, and (2) an African stock that gave gekkos today in terms of speciation, diver- rise to Holodactylus and Hemitheconyx. The sity of biology, and distribution (contin- magnitude of the morphological differences uous circumglobal distribution between ap- between the latter two genera may indicate proximately latitude 500 N. and latitude 500 that they did not evolve from a single ances- S.). Within the Gekkoninae, there appear to tral Eublepharis-like population. The ances- have been at least three levels of evolution tor of Coleonyx probably arrived in the New and radiation. At least two of the earlier World by way of the Bering land bridge gekkonine radiations seem to have centered through the continuous Paleocene Subtrop- in Africa and Madagascar and southwestern ical floral belt. The southern species group in Asia. The eastern part of the Paleotropical Coleonyx (elegans and mitratus) appears to area, in contrast to the west, is dominated by be more closely related to Eublepharis than "modern expanding dominants" that belong is the northern group (brevis and variegatus). primarily to the genera Cyrtodactylus, Ge- The occurrence of some populations of the hyra, Gekko, and Lepidodactylus. The few northern group in chaparral and subtropical endemic gekkonine genera of the New World scrub is probably indicative of the pre-desert do not appear to form a natural group and in habitat preference of the complex. most cases seem to have been independently The relatively primitive Diplodactylinae derived from Old World ancestors, the ma- are restricted to the Australian Region jority of which have an African distribution (today, Australia, New Caledonia and the today. Fortuitous trans-Atlantic rafting is Loyalty Islands, and New Zealand). It seems postulated as the general way in which the likely that the ancestral diplodactyline stock, ancestors of the gekkonine genera dispersed following its origin in southeast Asia from an to the New World. eublepharine ancestor, dispersed in the di- The Sphaerodactylinae are restricted to rection of Australia through the general re- the New World (primarily the Neotropical gion of the Indo-Australian archipelago, Region) and may also have been derived from probably during the late Mesozoic; the an African stock, possibly near the gek- Diplodactylinae are considered a member of konine genus Lygodactylus and its relatives. the autochthonous fauna of the Australian The dominance of the sphaerodactyline gek- Region. kos in the New World may be correlated with Concurrently, or nearly so, with the origin the absence of a single major gekkonine of the Diplodactylinae, it appears that the radiation from that part of its total range. APPENDIX 1 ALL OSTEOLOGICAL DATA presented in this Oedura Gray study were obtained from either cleared and 1. kesueurii (3)., marmorata (1), monilis (1)=, stained specimens or skeletons cleaned by robusta (1), tryoni (1). dermestid beetles of the following genera and Phyllurus Schinz cornutus (2)., milii (11)., platurus (3)x. species, unless otherwise stated in the text. sphyrurus (1) The number of specimens used in the study Pseudothecadactylus Brongersma follows the species name in parentheses. The australis (1) shape of the pupil was studied in living ma- Rhacodactylus Fitzinger terial of those species marked with a subscript auriculatus (1) x. The species marked with an asterisk belong Rhynchoedura Gunther to the Museum of Comparative Zoology, ornata (5)S Harvard University, osteological collection; Gekkoninae the remaining material is in my personal Afroedura Loveridge p. pondolia (1), transvaalica platyceps (1) collection. Agamura Blanford persica (1) Eublepharinae Ailuronyx Fitzinger Aeluroscalabotes Boulenger seychellensis (1) d. dorsalis (2), felinus* (1) Aristelliger Cope Coleonyx Gray cochranae barbouri (2), p. praesignis (4). brevis (15), e. elegans (4), mitratus (2), Blaesodactylus Boettger variegatus (including v. variegatus and v. boivini (1) sonoriensis) (47)s Briba Amaral Eublepharis Gray brasiliana (1) hardwickii (1), macularius (3) Bunopus Blanford Hemitheconyx Stejneger tuberculatus (1) caudicinctus* (1) Calodactylodes Strand Holodactylus Boettger aureus (1) africanus* (1) Chondrodactylus Peters Diplodactylinae angulifer (1) Bavayia Roux Cnemaspis Strauch cyclura (1) boulengerii (1), kandiana (1), kendaUii (1), Carphodactylus Giinther q. quattuorseriata (1), wynadensis (1) laevis (1). Colopus Peters Crenadactylus Dixon and Kluge wahlbergii (1) ocellatus (8)s Cosymbotus Fitzinger Diplodactylus Gray platyurus (1). alboguttatus (1), byrnei (1), c. ciliaris (4)=, c. in- Crossobamon Boettger termedius (10), conspicilatus (2)s, damaeus maynardi (1), orientalis (2) (7)x. elderi (1)=, masni' (2)s, michaetseni (1), Cyrtodactylus Gray pulcher (6)., savagei (1), spinigerus (5)s, annulatus (1), kachhensis watsoni (1), louisi- squarrosus (l)s, steindachneri (1), steno- adensis (1), marmoratus (1), nebulosus (1), dactylus (8)s, strophurus (2), taenicauda p. pelagicus (1)i, scaber (1) (4)., tessellatus (3), vittatus (14),s williamsi Ebenavia Boettger (5)s inunguis (1) Heteropholis Fischer Geckolepis Grandidier tuberculatus (1) maculata (1) Hoplodactylus Fitzinger Geckonia Mocquard duvauceiii (3), granulatus (4), pacificus (3) chazaliae (1) Naultinus Gray Gehyra Gray elegans (2). australis (2)s, mutilata (11)., oceanica (2), Nephrurus Gunther punctata (14)., variegata (16)s asper (2), laevissimus (1)s, 1. levis (5), w. Gekko Laurenti wheeleri (1) g. gecko (6)X, vittatus (2) 53 54 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 135 Gymnodactylus Spix tus (3), sokotranus (1) g. geckoides (1) Ptenopus Gray Hemidactylus Oken garrulus (1) b. brooki (2)s, b. angulatus (1), b. haitianus Ptychozoon Kuhl (5), flaviviridis (1), frenatus (13)., garnotii kuhli (1) (1), giganteus (1), karenorum (5), leschen- Ptyodactylus Goldfuss aultii (1), maculatus (1), persicus (1), t. tur- h. hasselquistii (1), h. ourdii (1) cicus (2). Quedenfeldtia Boettger Hemiphyllodactylus Bleeker trachyblepharus (4) t. typus (3) Rhoptropella Hewitt Heteronotia Wermuth ocellata (1) binoei (11)., spelea (1) Rhoptropus Peters Homonota Gray afer (1), b. bradfieldi (1) darwinii (2), gaudichaudii (3), horrida (7) Saurodactylus Fitzinger Homopholis Boulenger fasciatus (2), mauritanicus brosseti (4) fasciata subsp. (1), wahlbergii (1) Stenodactylus Fitzinger Lepidodactylus Fitzinger petrii (1), s. sthenodactylus (6), s. mauritanicus guppyi (1), lugubris (13)., pumilis (2), wood- (1) fordi (1) Tarentola Gray Lygodactylus Gray americana (1), annularis (1), m. mauritanica capensis (2), conraui (1), p. picturatus (1) (5)., neglecta (1) Microgecko Nikolsky Teratolepis Gunther helenae (2) albofasciata (3), fasciata (7) Millotisaurus Pasteur Teratoscincus Strauch mirabilis (1) microlepis (4)., scincus (5). Narudasia Methuen and Hewitt Thecadactylus Goldfuss festiva (1) rapicauda (2) Pachydactylus Wiegmann Tropiocolotes Peters b. bibronii (7)., b. turneri (1), c. capensis (1), tripolitanus algericus (1) geitje (1) Uroplatus Dum&ril Palmatogecko Anderson f. fimbriatus (1) rangei (2) Sphaerodactylinae Perochirus Boulenger Coleodactylus Parker guentheri (2) amazonicus (2) Phelsuma Gray Gonatodes Fitzinger barbouri (1)=, cepediana (2), laticauda (2)=, a. albogularis (2), a. fuscus (3)s, a. notatus (1), lineata subsp. (1), m. madagascariensis (1), antillensis (3), atricucullaris (3), humeralis m. kochi (1). (2), ocellatus (1), v. vittatus (2) Phyllodactylus Gray Lepidoblepharis Peracca guentheri (1), h. homolepidurus (2)., julieni microlepis (2), (1), lanei subsp. (1), marmoratus (11)., p. Pseudogonatodes Ruthven porphyreus (1), t. tuberculosus (2)., unctus barbouri (2) (1)s, xanti nocticolus (1) Sphaerodactylus Wagler Phyllopezus Peters argus henriquesi (3), cinereus (2), difficilis p. pollicaris (1), p. przewalskii (2) (2), goniorhynchus (2), inaguae (2), m. ma- Pristurus Ruippell crolepis (2), mariguanae (1), mertensi (1), carteri collaris (1), crucifer (2), f. flavipuncta- parkeri (2), richardsonii gossei (1), torrei (1) LITERATURE CITED AMARAL, AFRANIO DO with the description of a new species. 1935. Estudos sobre lacertilio Neotropicos. Cimbebasia, no. 1, pp. 1-18. III Um novo genero e duas novas 1962b. Observations on the temperature toler- especies de geckonideos e uma nova ance of lizards in the central Namib raga de amphisbenido, procedentes do desert, South West Africa. Ibid., no. 4, Brasil Central. Mem. Inst. Butantan, pp. 1-5. vol. 9, pp. 253-256. BRATTSTROM, B. H. ANDERSON, JOHN 1965. Body temperatures of reptiles. Amer. 1896. 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PLATES 1-5

BULLETIN AMER. Mus. NAT. HIST. VOL. 135, PLATE 1

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1. Shape of the gekkonine pupil; Gehyra variegata, from Lowood, Queensland, Australia. Gehyra was placed in the Gekkoninae by Underwood (1954). 2. Shape of the diplodactyline pupil; Phyllurus cornutus, from Mt. Tamborine, Queensland, Australia. Phyllurus was placed in the Diplodactylinae by Underwood (1954) BULLETIN AMER. Mus. NAT. HIST. VOL. 135, PLATE 2

1, 2. Shapes of the gekkonine pupil. 1. Diplodactylus williamsi (emarginations poorly devel- oped), from the Warrumbungle Mountains, New South Wales, Australia. 2. Diplodactylus c. ciliaris, from southern Queensland, Australia. Diplodactylus was placed in the Diplodactylinae by Underwood (1954) BULLETIN AMER. Mus. NAT. HIST. VOL. 135, PLATE 3

1. Shape of the gekkonine pupil; Diplodactylus ciliaris intermedius, from Nymagee, New South Wales, Australia. 2. Shape of the diplodactyline pupil; Diplodactylus conspicillatus, from central Queensland, Australia BULLETIN AMER. Mus. NAT. HIST. VOL. 135, PLATE 4

U.... 1, 2. Shapes of pupils intermediate between the gekkonine type and the diplodactyline type. 1. Teratoscincus scincus,from West Pakistan. 2. Teratoscincus microlepis, from West Pakistan. Teratoscincus was placed in the Diplodactylinae by Underwood (1954) BULLETIN AMER. Mus. NAT. HIST. VOL. 135, PLATE 5

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i I211 tI ,I 3 28 4 1. Shape of the diplodactyline pupil; Naultinus elegans, from New Zealand. Naultinus was placed in the Diplodactylinae by Underwood (1954). 2, 3. Ventral views of the cranium and thoracic regions of Gekko g. gecko, showing the calcified endolymphatic sacs (arrow). 2. Female, sac present. 3. Male, sac absent