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Algyroides fitzingeri, Algyroides marchi, Algyroides moreoticus, Algyroides nigropunctatus, Lacerta agilis, Lacerta lepida, Lacerta princeps, Lacerta schreiberi, Lacerta strigata, Lacerta trilineata, Lacerta viridis, Lacerta andreanszkyi, Lacerta armeniaca, Lacerta bedriagae, Lacerta brandtii, Lacerta cappadocica, Lacerta caucasica, Lacerta chlorogaster, Lacerta cyanura, Lacerta danfordi, Lacerta derjugini, Lacerta dugesii, Lacerta fraasii, Lacerta graeca, Lacerta horvathi, Lacerta jayakari, Lacerta laevis, Lacerta monticola, Lacerta mosorensis, Lacerta oxycephala, Lacerta parva, Lacerta perspicillata, Lacerta praticola, Lacerta rudis, Lacerta saxicola, Lacerta vivipara, Gallotia atlantica, Gallotia galloti, Gallotia simonyi, Podarcis erhardii, Podarcis filfolensis, Podarcis hispanica, Podarcis lilfordi, Podarcis melisellensis, Podarcis milensis, Podarcis muralis, Podarcis peloponnesiaca, Podarcis pityusensis, Podarcis sicula, Podarcis taurica, Podarcis tiliguerta, Podarcis wagleriana, Psammodromus algirus, Psammodromus blanci, Psammodromus hispanicus, Psammodromus microdactylus.

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The basic anatomy of the lacertid hemipenis (intromittent organ) and methods for its investigation are described. In many members of the Lacertidae, the hemipenis has a structure quite unlike that of other squamate reptiles: the distal lobes of the retracted organ are complexly folded and there is a well-defined supporting structure of dense connective tissue, the armature. This incorporates blood sinuses and has an intramuscular portion embedded in the m. retractor penis magnus and two club-shaped bodies, the clavulae, that support the lobes in the erect organ. Unarmatured hemipenes occur in some lacertids and, like those of other squamates, possess sac-like lobes in the retracted state, but they are singular in having the lobes invested by the m. retractor penis magnus. It is argued that many of these apparently primitive hemipenes are in fact secondary derivatives of the armatured type. There is considerable inter-specific variation in hemipenial structure which is described systematically. In some cases this involves differences in size, asymmetry and simplification, which may arise as physical isolating mechanisms and is useful in distinguishing otherwise very similar species, particularly in the genus Mesalina (p. 1253). Other shared derived hemipenial features provide useful information about relationships between species and higher taxa and a summary of the hypotheses that they support is given (p. 1254).

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Differences in surface structure (ober- hautchen) of body scales of lacertid lizards involve cell size, shape and surface profile, presence or absence of fine pitting, form of cell margins, and the occurrence of longitudinal ridges and pustular projections. Phylogenetic information indicates that the primitive pattern involved narrow strap-shaped cells, with low posteriorly overlapping edges and relatively smooth surfaces. Deviations from this condition produce a more sculptured surface and have developed many times, although subsequent overt reversals are uncommon. Like variations in scale shape, different patterns of dorsal body microornamentation appear to confer different and conflicting performance advantages. The primitive pattern may reduce friction during locomotion and also enhances dirt shedding, especially in ground-dwelling forms from moist habitats. However, this smooth microornamentation generates shine that may compromise cryptic coloration, especially when scales are large. Many derived features show correlation with such large scales and appear to suppress shine. They occur most frequently in forms from dry habitats or forms that climb in vegetation away from the ground, situations where dirt adhesion is less of a problem. Microornamentation differences involving other parts of the body and other squamate groups tend to corroborate this functional interpretation. Microornamentation features can develop on lineages in different orders and appear to act additively in reducing shine. In some cases different combinations may be optimal solutions in particular environments, but lineage effects, such as limited reversibility and different developmental proclivities, may also be important in their genesis. The fine pits often found on cell surfaces are unconnected with shine reduction, as they are smaller than the wavelengths of most visible light.

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DNA sequence indicates the Lacertidae contain two subfamilies, Gallotiinae and Lacertinae, the latter comprising two monophyletic tribes, the Eremiadini of Africa and arid southwest and central Asia, and the Lacertini of Europe, northwest Africa and southwest and east Asia. Relationships within the 108 species of Lacertini are explored using mtDNA (291 bp cytochrome b; 329 bp 12S rRNA for 59 nominal species, and reanalysis of the data of Harris et al. 1998, and Fu 2000). The morphology of the tribe is reviewed and 64 of its characters (equivalent to 83 binary ones) also used to assess relationships. The Lacertini are assigned to 19 monophyletic units of 1 to 27 species, recognised here as the following genera (contents are indicated in brackets): Algyroides, Anatololacerta gen. nov. (L. danfordi group), Apathya (L. cappadocica group), Archaeolacerta (L. bedriagae), Dalmatolacerta gen. nov. (L. oxycephala), Darevskia (L. saxicola group), Dinarolacerta gen. nov. (L. mosorensis), Hellenolacerta gen. nov. (L. graeca), Iberolacerta (L. monticola group), Iranolacerta gen. nov. (L. brandtii and L. zagrosica), Lacerta s. str. (sand and green lizards, L. agilis group), Parvilacerta gen. nov. (L. parva and L. fraasii), Phoenicolacerta gen. nov. (L. laevis group), Podarcis (wall lizards), Scelarcis (L. perspicillata), Takydromus (Asian grass lizards), Teira (L. dugesii), Timon (ocellated lizards, L. lepida group) and Zootoca (L. vivipara). Both mtDNA and morphology indicate that Lacerta and Timon are sister taxa, and DNA suggests further possible relationships among genera (Fig. 1, p. 6). Neither DNA nor morphology indicates that the archaeolacertas (sometimes formalised as Archaeolacerta sens. lat.) form a clade. Instead, they are representatives of an ecomorph associated with living on rock exposures and using the narrow crevices that these contain. The Lacertidae probably arose in the European area, with the Gallotiinae later reaching Northwest Africa and the Canary Islands, and the ancestor of the Eremiadini invading Africa in the mid-Miocene. The Lacertini spread through much of their present European range and diversified, perhaps largely by repeated vicariance, around 12–16 My ago, producing the ancestors of the present mainly small-bodied genera, which then underwent often modest speciation. Three units spread more widely: the Lacerta-Timon clade of large-bodied lizards probably dispersed earliest, followed by Algyroides and then Podarcis. Overall, European Lacertidae show a pattern of repeated spread, often accompanied by restriction of previous groups. Expansion of Lacertini may have displaced earlier lacertid lineages from all or much of Europe; while spread of Podarcis may have restricted many other genera of Lacertini. The earlier expansion of the Lacerta-Timon clade probably did not have this effect, as difference in adult body size restricted competitive interaction with other forms. Several invasions of more distant areas also occurred: of East Asia by Takydromus over 10 My ago, and more recently of northwest Africa by Podarcis, Scelarcis and Timon, and Madeira by Teira. Relationships within the Eremiadini estimated from both mtDNA, and nDNA differ considerably from those based on morphology. They indicate relatively mesic forms may have diversified widely across Africa and given rise to at least three independent invasions of arid habitats. MtDNA also indicates that Lacerta andreanskyi belongs in the Eremiadini and may occupy a basal position there. It is assigned to a further new genus, Atlantolacerta gen. nov.

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Archaeolacerta s. l., in the currently utilized sense results to be a polyphyletic taxon, composed of three monophyletic and phylogenetically well differentiated taxa: a)-Archaeolacerta (s. str.) Mertens, 1921, which includes three species: A. bedriagae, A. oxycephala, and A. mosorensis, distributed by the northern part of the Central Mediterranean (Corsica, Sardinia, and west Balcanic Peninsula). His most related genera seem to be Teira (his adelphotaxon in our study), Apathya, and Omanosaura. b)-Iberolacerta gen. nov., with two subgenera: Iberolacerta s. str. and Pyrenesaura subgen. nov. includes six species: I. monticola, I. cyreni, I. bonnali, I. aranica, I. aurelioi, and I. horvathi. They are distributed by the mountains of Western Europe (Iberian Peninsula, Pyrenees, Central and Eastern Alps and the north of the Dinaric Chains). His adelphotaxon are the Caucasian and Near East species of Darevskia gen. nov. c)-The third taxa is Darevskia gen. nov., which includes the species of the `L.` saxicola complex besides `L.` derjugini, `L.` praticola, and `L.` chlorogaster. They are distributed by Eastern Europe, Caucasus, and Near East. Other clear relationships among some taxa of the Eurasian Radiation [= `Eurasische linie` from (Mayer and Benyr, 1994)] have been found: Algyroides seems to be the sister group of the species considered of uncertain phylogenetic relationships belonging to the `L.` danfordi-laevis group and of Podarcis. `L.` brandtii seems to be a very primitive species within the Eurasian Radiation. Omanosaura and Apathya appear as sister taxa. `L.` graeca occupies a very basal position in the sister group of Podarcis and relatives (see above). `L.` andreanskyi is the sister species of the Darevskia nov. and Iberolacerta nov. clade. The assimilation of `L.` andreanskyi to Teira is very problematic. Also the `L.` parva group seems to be related to Timon. Some groups of species like `L.` brandtii, `L.` parva-fraasii and `L.` danfordi-laevis probably merit generic rank, but it is necessary a more deep study before to take a decision.

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The microornamentation of the scales (oberhautchen) has been studied by means of enamel casts (in negative), or with detached skin pieces (positive cast in the upper face or negative in their lower face of the scales) and its observation by transparency with optical microscopy at 40x, 400x and 1000x. In this study we have found a remarkable uniformity in all genera of Lacertini studied (already known, although significantly expanding the number of species previously studied). In light of the results obtained, it seems that the use of the microornamentation of the scales in taxonomy is limited. There is a remarkable degree of variation and probably of homoplasy, as it happens in so many characters of Lacertini. Nor is it clearly linked to certain conditions of the environment, although it may have a certain importance in mechanisms such as evapotranspiration and perhaps in the crypsis through its influence on the reflectance of the scales. These scales can present protuberances (like small tubercles) on their surface (derived character) in Algyroides (the four species), and in the case of Algyroides marchi also seems to present small pits on its scale surface. In most lacertids the cells of the “oberhautchen” are usually narrow (or short anteroposteriorly, if preferred), between 1 and 4 μm, having the appearance of ribbons or transverse straps. Smaller sizes (derivated) appear more or less marked in Algyroides spp, Darevskia praticola complex, Parvilacerta spp and in Dinarolacerta mosorensis (although not in D. montenegrina) and is difficult to interpret. Except in Dinarolacerta, in the other species it coincides that they are ground or ground-rock interface species, and the coarser stripes could have to do with reflectance (imitating the vegetation or the medium between which they move, according to the hypothesis of Allam et al.). In the case of Dinarolacerta, very saxicolous, it is probably the sister group of Algyroides and the common morphology could have a phylogenetic origin linked to its relationship with Algyroides. There is also no relationship with moisture since some come from dry places and others are from very wet areas. The posterior flange of the cells may be slightly mounted in the next cell (primitive character) but appears quite raised (derived character) in Algyroides nigropunctatus (much less in A. moreoticus and A. marchi, and apparently little or nothing in A. fitzingeri). The rear flange of the cells can be smooth, corrugated or notched. In our samples, irregular (and even dentate) posterior ridges appear in numerous Darevskia such as D. derjugini, D. parvula, D. raddei complex [D. raddei raddei, D. r. vanensis and D. nairensis], in part of the group of D. rudis [D. rudis sspp. and D. bithynica sspp.], several Iberolacerta (I. bonnali, I. horvathi and I. monticola astur), as well as in Teira dugesii. The character appears, although less marked in Algyroides (more in A. moreoticus, but less marked or barely visible in the others), in Hellenolacerta graeca, and other Iberolacerta (I. aurelioi, I. martinezricai, and scarcely marked in I. cyreni). Very little marked in Darevskia mixta, somewhat more in D. dryada and none in D. clarkorum, and also appears in the group of D. saxicola (D. saxicola, D. brauneri brauneri, D. b. darevskii, D. lindholdmi, D. szczerbaki), Dalmatolacerta oxycephala, Dinarolacerta mosorensis (only in the Biokovo sample, and not in Durmitor or D. montenegrina), Apathya cappadocica, in some places of the scales of Parvilacerta fraasii (but not in P. parva) and very little in D. (p) hungarica; also in the remaining group of D. rudis (D. valentini valentini, D. v. lantzicyreni, D. rudis bolkardaghica, D. portschinskii), and some parthenogenetic species (D. armeniaca, D. dahli, D. rostombekowi) but not in D. unisexualis, D. uzzelli, D. sapphirina, D. bendimahiensis or in the triploid hybrid between D. unisexualis and D. nairensis. In these parthenogenetic species it seems a general rule that the character of the crenulation or irregularity of the posterior flange of the cells resembles that of the paternal rather than the maternal species. The exception is the triploid hybrid [arisen from the hybridization of D. unisexualis (parthenogenetic female, without the character) and a male of D. nairensis (with fairly developed character)] that lacks character, and in this case is more similar to the maternal species of which has two genetic sets compared to only one of the paternal one.

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Near Ayoun Assiman (Sannin Mountains) Lacerta fraasii was relatively abundant with at least one individual per 30 m2 Among melting snow patches most animals were found close to, or in the Astralagus bushes growing on the stony slopes, which they often shared with one or more Mabuya vittata. Temperatures ranged from near freezing to 25,8°C. Since snow covers the area again in October, the lizards have an active season of maximally six months. Analysis of faecal pellets revealed a varied diet, with spiders and beetles as main components. The calm L, fraasii adapt easily to life in terraria and prove to be surprisingly active diggers, although they also climb well. High teperatures are avoided.

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Based on observations at a previously unsurveyed locality at 1950 m in ahitude in the Sannin Mountains (Ayoun Assiman). Lacerta fraasii proved to he much more abundant than was previously assumed. A conservative pre- liminary estimate is one lizard per 30m! in this area. although the density is probably much higher. The tirst observations were made May 9th between 8h30 and 12h00. during which time 23 animals were caught and measured: the first just after 9h00. Most lizards were found close to, or in, the very prickly, cushion-like Astralagus bushes that grow on the stony slopes. Each bush appeared to be inhabited by at least two L. fraasii, and often also by one or more Mahuya vittata. In general, vegetation was very scarce. The snow had just started to melt, and some animals sunned themselves only centimetres away from the snow. Tem- peratures ranged from slightly above freezing early in the morning, to 10.4oc in the shade and 25.8°C in the sun around noon. Presuma- bly the lizards had very recently come out of hibernation, as also indicated by the higher number of males (13), in comparison to females (8) and subadults (2). Because snow begins to fall again in October, the lizards have an active season of six months or less. An analysis of faecal pellets revealed a remarkably varied diet of arthropods in early spring, however spiders and beetles were the main components. Although lateral spots appear blue in alcohol-preserved specimens, and are report- ed as such in the literature, most spots have an unmistakable green tinge and the smaller posterior ones are often yellow on living males. The greenish-blue spots are frequently paler or missing on females. Both sexes may be yellow or white ventrally. A bright band of green and yellow with black spots occurs in the transition zone between the dorsals and ventrals of males. Males reach a longer head-body length (55 nun) than females (51 mm). Male tail lengths were also longer (105 mm) than those of females (76 mm). Lebanese mountain lizards maintained in terraria are calm and not overly shy. They are surprisingly active dig- gers, although they also climb well. High temperatures are avoided.

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An as yet undiagnosed illness of lacertid lizards of the genera Algyroides, Gallotia, Lacerta, and Algyroides is described. The main symptoms are runny eyes, apathy, food und water refusal. The illness is almost always fatal. Antibiotics like tetracyclines and sulphathiazole had no effect. It is not known whether the disease is contagious. Some species like green lizards seem to be more susceptible. Stress is thought to possibly play an important role in this disease.

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The interspecific relationships among female size, clutch size, egg size, and hatchling size were examined for 64 European lacertids. The eggs of all species increased linearly in both linear dimensions and mass during incubation. Across species initial egg mass was positively correlated with juvenile mass, with an allometric relationship exponent of 0.87. Initial egg mass across species increased proportionally with female mass to the power of 0.57. Moreover, an increase in maternal mass was also accompanied by an increase in clutch size. The number of eggs per clutch across species scaled with female mass to the power of 0.39. Removing the effect of female mass resulted in a negative correlation between egg mass and clutch size. Species for which the average egg size was lower than expected on the basis of female mass, tended to have larger relative clutch size. The total egg mass per clutch was about one third of female mass (exponent 0.94).

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In recent years there has been an exponential increase in the amount of published DNA sequences, as it has become one of the most popular sources of data for reconstructing phylogenies. A number of studies have attempted to resolve the relationships of groups of lacertids using mitochondrial DNA sequence data, in particular Podarcis and Gallotia (e.g. THORPE et al., 1994; 1996; GONZALEZ et al., 1996; FU et al., 1997; HARRIS, 1997; HARRIS et al., 1998a; 1999; CASTILLA et al., 1999a,b). Reassessment of these data suggest some alternative phylogenies to those previously published, and also highlight possible problems. Two studies have attempted to unravel the phylogeny of the whole family using mitochondrial DNA sequences (FU, 1998; HARRIS et al., 1998b). By combining these essentially congruent data sets, and reanalysing levels of support for the phylogenies produced, a more complete estimate of relationships across the family is produced. This is then compared to alternative sources of evidence, primarily morphological (ARNOLD, 1989), biochemical (MAYER & BENYR, 1994) and karyological (OLMO et al., 1993). Reasons for discrepencies are discussed, as are the relative advantages and disadvantages of the different sources of phylogenetic inference.

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DNA sequences from parts of the 12S, 16S and cytochrome b mitochondrial genes, which totalled 1049 aligned base pairs, were used to estimate the relationships of 49 species of Lacertidae, including representatives of 19 out of the 23 recognized genera and 23 species of the paraphyletic genus Lacerta. These data were used, together with morphological information, to estimate the relationships within the family. Molecular evidence corroborates the monophyletic status of many genera and species groups originally based on morphology. It indicates that Psammodromus forms a clade with Gallotia, which is the sister taxon of all other lacertids. These comprise three units: the primarily Afrotropical armatured group; the largely Oriental Takydromus; and the west Palaearctic Lacerta and its derivatives, Podarcis and Algyroides. Morphology also supports the first three assemblages, but suggests that they are derived from a paraphyletic Lacerta. Within Lacerta and its allies, DNA sequence analysis corroborates the affinity of some members of each of the subgenera Lacerta s. str. and Timon, and of the L. saxicola group. It also supports the relationship of L. monticola, L. bonnali and L. horvathi, and suggests that the L. parva–L. fraasi clade and L. brandti are not related to Psammodromus–Gallotia, as morphology indicates, but instead are associated respectively with the L. danfordi and L. saxicola groups. DNA sequence data provide additional evidence that the eastern Arabian `Lacerta` jayakari and `L.` cyanura are members of the armatured clade and also sister species. Our analysis supports an origin for present lacertids in west Eurasia. The armatured clade invaded Africa, probably in the mid-Miocene, spreading widely and evolving increasingly xeric-adapted forms, one lineage of which later moved back into the Palaearctic. `Lacerta` jayakari and `L.` cyanura are assigned to Omanosaura, Lutz and Mayer 1986. The name Gallotiinae Cano, Baez, Lopez-Jurado and Ortega, 1984 is available for the Gallotia–Psammodromus clade, Eremiainae Shcherbak 1975 for the armatured clade and Lacertinae for Lacerta, Podarcis and Algyroides. Two new subgenera of Lacerta are proposed here: Caucasilacerta for L. saxicola and its allies, and Parvilacerta for L. parva and L. fraasi.

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The evolutionary diversification of many terrestrial vertebrate groups is strongly linked to climatic events in the Cenozoic, the period from 65 Million years ago to today when modern animals first appeared. I investigated the effects of Cenozoic climate change on the taxonomic and morphological diversification of the Old World lizard family Lacertidae, with particular emphasis on the African radiation. African lacertids exhibit an unusual pattern of diversification, in which their highest species richness occurs in deserts north and south of the equator, despite being spread throughout the continent. This disparity is particularly surprising given that desert lacertids are thought to be evolutionarily younger than their mesic-dwelling relatives, suggesting increased diversification rates in arid habitats. To identify the evolutionary factors underlying this pattern, I use a combination of phylogenetic, morphological and ecological techniques. In Chapter 1, I apply Bayesian methods and fossil-based calibrations to molecular sequence data to construct a time-calibrated phylogeny for Lacertidae. I estimate that the family arose in the early Cenozoic, with the majority of their African radiation occurring in the Eocene and Oligocene. In Chapter 2, I describe changes in lacertid body shape across biomes and substrates, and find widespread morphological convergence in similar habitat types. I suggest that in addition to foraging demands, fluctuating and extreme climatic conditions, largely driven by precipitation and temperature, contribute to morphological convergence across independent arid-dwelling clades. Finally, I test if ancestral transitions in ecology, morphology, and rates of diversification temporally coincide with paleoclimatic events in the Cenozoic. I use High Resolution X-ray Computed Tomography to characterize changes in the skull related to life in arid habitats, and apply maximum likelihood methods to test if the origins of those traits temporally coincide with significant shifts in habitat, diversification rates and climatic changes. My results show that African lacertids experienced three major peaks in diversification, accompanied by the evolution of suites of arid-adapted morphological traits. These changes coincide with climatic shifts in Africa, including the transition from closed forests to open grasslands and savanna in the late Oligocene, prior to the peak temperatures of the mid-Miocene Climatic Optimum, and following the formation of the Benguela current leading to hyper-aridity in southern Africa. I conclude that deserts are important centers for reptile evolution, but that expected changes in climate due to global warming may outpace the ability of arid-dwelling species to adapt and persist in the future.

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Background: Although current molecular clock methods offer greater flexibility in modelling evolutionary events, calibration of the clock with dates from the fossil record is still problematic for many groups. Here we implement several new approaches in molecular dating to estimate the evolutionary ages of Lacertidae, an Old World family of lizards with a poor fossil record and uncertain phylogeny. Four different models of rate variation are tested in a new program for Bayesian phylogenetic analysis called TreeTime, based on a combination of mitochondrial and nuclear gene sequences. We incorporate paleontological uncertainty into divergence estimates by expressing multiple calibration dates as a range of probabilistic distributions. We also test the reliability of our proposed calibrations by exploring effects of individual priors on posterior estimates. Results: According to the most reliable model, as indicated by Bayes factor comparison, modern lacertids arose shortly after the K/T transition and entered Africa about 45 million years ago, with the majority of their African radiation occurring in the Eocene and Oligocene. Our findings indicate much earlier origins for these clades than previously reported, and we discuss our results in light of paleogeographic trends during the Cenozoic. Conclusion: This study represents the first attempt to estimate evolutionary ages of a specific group of reptiles exhibiting uncertain phylogenetic relationships, molecular rate variation and a poor fossil record. Our results emphasize the sensitivity of molecular divergence dates to fossil calibrations, and support the use of combined molecular data sets and multiple, well-spaced dates from the fossil record as minimum node constraints. The bioinformatics program used here, TreeTime, is publicly available, and we recommend its use for molecular dating of taxa faced with similar challenges.

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This paper reports more than 400 original data on the Lebanese herpetofauna (covering 5 amphibians and 44 reptiles), deriving from museum collections and recent field observations. The most interesting data concern: (a) Cyrtopodion amictopholis, a species known only from Mt. Hermon, reported for the first time from Mt. Lebanon Range; (b) Lacerta fraasi, previously con- sidered endemic to the Mount Lebanon Range, also recorded from Antilebanon; (c) the occur- rence of Macrovipera lebetina is confirmed with certainty from two localities in the north. New records are given for many species known in Lebanon only on the basis of very few and often old reports.

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Several recent papers have reviewed the life and work of French herpetologist Louis Amédée Lantz. They have detailed the composition of his collections deposited in several museums. However, since then, several other important specimens from his collections deposited at the Natural History Museum (NHM, UK) have come to light and we here present all of them in detail. We discovered paralectotypes of Lacerta saxicola obscura Lantz & Cyrén (BMNH 1918.11.21.5–7), syntypes of Lacerta boemica Sukhov (BMNH 1960.1.4.26–30, BMNH 1965.337–342) and Lacerta viridis media Lantz & Cyrén (BMNH 1960.1.4.25, 1966.512). We also identified numerous specimens from the French Mediterranean islands in Lantz’s collection deposited at the NHM, some of which represent the first reported specimens of their species from certain islands. We here provide data on all these specimens. We also place the Mediterranean island specimens from the Lantz collection in their historical context and emphasize the historical and taxonomic value of these collections.

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Aim Body size is instrumental in influencing animal physiology, morphology, ecology and evolution, as well as extinction risk. I examine several hypotheses regarding the influence of body size on lizard evolution and extinction risk, assessing whether body size influences, or is influenced by, species richness, herbivory, island dwelling and extinction risk. Location World-wide. Methods I used literature data and measurements of museum and live specimens to estimate lizard body size distributions. Results I obtained body size data for 99% of the world`s lizard species. The body size–frequency distribution is highly modal and right skewed and similar distributions characterize most lizard families and lizard assemblages across biogeographical realms. There is a strong negative correlation between mean body size within families and species richness. Herbivorous lizards are larger than omnivorous and carnivorous ones, and aquatic lizards are larger than non-aquatic species. Diurnal activity is associated with small body size. Insular lizards tend towards both extremes of the size spectrum. Extinction risk increases with body size of species for which risk has been assessed. Main conclusions Small size seems to promote fast diversification of disparate body plans. The absence of mammalian predators allows insular lizards to attain larger body sizes by means of release from predation and allows them to evolve into the top predator niche. Island living also promotes a high frequency of herbivory, which is also associated with large size. Aquatic and nocturnal lizards probably evolve large size because of thermal constraints. The association between large size and high extinction risk, however, probably reflects a bias in the species in which risk has been studied.

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Lacertinae is one of the three lacertid lizard subfamilies with a geographical distribution confined to the Palaearctic. Several past attempts to reconstruct its phylogeny resulted in unresolved bush-like topologies. We address the question of whether the lack of resolution is due to insufficient data or whether this lack reflects a rapid succession of speciation events. We analyzed four partial and one complete gene sequences from mitochondrial and nuclear genomes, totalling roughly 3600 bp. We included 29 species representing all 19 genera suggested in recent revision of Lacertinae [Arnold, E.N., Arribas, O., Carranza, S., 2007. Systematics of the palaearctic and oriental lizard tribe Lacertini (Squamata: Lacertidae: Lacertinae), with descriptions of eight new genera. Zootaxa 1430, 1–86]. The resulting phylogeny, first, corroborates monophyly at the genus level for the suggested genera, as well as the finding that Atlantolacerta andreanskyi, until recently part of Lacertinae, belongs to the subfamily Eremiadinae. Second, we find that increasing the sequence length and combining multiple nuclear and mitochondrial sequences did not resolve the polytomy, suggesting that the inferred topology indicates a multiple cladogenesis within a short geological period, rather than a methodical artefact. Divergence time estimates, based on previous estimates of several node ages, range from 13.9 to 14.9 million years for the radiation event, however with very broad confidence interval. To associate the radiation with a narrower geological time we consider palaeogeographic and palaeoclimatic data, assuming that the Lacertinae probably evolved in Central Europe andWAsia after the collision of Africa and Eurasia. We suggest that this radiation may date to the late Langhian (ca. 14–13.5 million years) when geological events caused abrupt changes in regional water–land distribution and climate, offering a window of distinct conditions.

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Many animals display complex colour patterns that comprise several adjacent, often contrasting colour patches. Combining patches of complementary colours increases the overall conspicuousness of the complex pattern, enhancing signal detection. Therefore, selection for conspicuousness may act not only on the design of single colour patches, but also on their combination. Contrasting long- and short-wavelength colour patches are located on the ventral and lateral surfaces of many lacertid lizards. As the combination of long- and short-wavelength-based colours generates local chromatic contrast, we hypothesized that selection may favour the co-occurrence of lateral and ventral contrasting patches, resulting in complex colour patterns that maximize the overall conspicuousness of the signal. To test this hypothesis we performed a comparative phylogenetic study using a categorical colour classification based on spectral data and descriptive information on lacertid coloration collected from the literature. Our results demonstrate that conspicuous ventral (long wavelength-based) and lateral (short wavelength-based) colour patches co-occur throughout the lacertid phylogeny more often than expected by chance, especially in the subfamily Lacertini. These results suggest that selection promotes the evolution of the complex pattern rather than the acquisition of a single conspicuous colour patch, possibly due to the increased conspicuousness caused by the combination of colours with contrasting spectral properties.

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The two endangered Lebanese lacertid lizards Phoencilacerta kulzeri and Parvilacerta fraasii are sympatric with the skink Trachylepis vittata in regions of high altitude, between 1900 and 2100m. Field studies were conducted on their habitat use, microhabitat preferences and diet. The results show habitat differences between the three species in terms of physical structure and types of vegetation associated with these habitats. P. kulzeri is mostly scansorial in rocky habitats while T. vittata and P. fraasi are mostly ground-dwelling. The habitats of P. kulzeri is more fragmented than that of the other two species. Trachylepis vittata, which is slightly larger than the two lacertids, tends to eat larger prey but the diet of P. kulzeri is the least diverse. The lacertids continue to be active as long as the weather permits, sometimes until late November but T. vittata virtually disappears as of early October.