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Morphologic diversity was studied in 129 species of lacertid lizards and their relationship with ecology by means of comparative analysis on seven linear morphometric measurements. Body size is the most important variable determining, a continuum among small bodied species and larger ones independently evolved through the lacertid phylogeny. This variable is strongly and positively correlated with the others masking the patterns of morphologic diversity. Multivariate analysis on size-adjusted variables show a negative covariation among relative tail and limb length. Remarkably, arboreal and semiarboreal species (Takydromus and the Equatorial African clade) appeared two times independently during the evolution of lacertids and are characterized by extremely long tails, and relatively long forelimbs in comparison with hindlimb length. The arboreal and glider lizard Holaspis with their short tail constitute the only exception. Another case of convergence is found by some species dwelling into dense vegetation or grass (Tropidosaura, Lacerta agilis, Takydromus amurensis or Zootoca) which have long tails and short limbs. On the opposite, species living in deserts, steppes or scrublands with scarce vegetation isolated into extended open areas have developed long hindlimbs and short forelimbs to achieve higher speed and maneuverability This is especially the case of Acanthodactylus and Eremias.

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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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In this paper we deal on the ultraviolet color (invisible to us): where we can find it, the capability of animals to see it and the advantages that this color perception offers to them. As the simplest way to detect it is the photography, we describe and review how to photograph the UV, as a result of 15 years of amateur experience, searching and testing nearly in complete blindness due to the lack of practical information about “how to do it”. We describe the different kinds of photography (chemical and digital); the cameras and objectives suitable (both astronomically expensive ones and cheap options); what are the best characteristics that the objectives should have for this purpose; the films suitable for their use in chemical photography; the different filters (current or discontinued) manufactured along the years; and the subtle combinations among the different materials to obtain pure UV photographs. This kind of scientific photography is mainly used in forensics, forgery detection, art dermatology and less in Natural History, despite the fact that a great part of animals see this color and use it in important questions of their biology as the social behavior, mate choice or the food search.

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Animals communicate via a variety of sensory channels and signals. Studies on acoustic and visual communication systems suggest that differences in the physical environment contribute to the variety of signalling behaviour, with species investing in those signals that are transmitted best under the local conditions. Whether or not environmental tuning also occurs in chemical communication systems has received much less attention. In the present study, we examined the effect of several aspects of the physical environment on the chemical communication system of lacertid lizards (family Lacertidae). The numbers of femoral pores are used as a proxy reflecting how much a particular species invests in and relies upon chemical signalling. Femoral pores are specialized epidermal structures that function as a secretion channel for the waxy substance produced by glands. In some lacertid species, the secretion carries infochemicals that play an important role in social communication. The number of femoral pores varies considerably among species. We have compiled data on femoral pore numbers for 162 species and tested for the effects of climate and substrate use. After correcting for body size and taking the phylogenetic relationships among the species into account, we found no effect of climate conditions or latitude on species pore numbers. Substrate use did affect pore numbers: shrub-climbing species tended to have fewer femoral pores than species inhabiting other substrates.

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1. The signals that animals use to communicate often differ considerably among species. Part of this variation in signal design may derive from differential natural selection on signal efficacy: the ability of the signal to travel efficiently through the environment and attract the receiver`s attention. For the visual and acoustic modalities, the effect of the physical environment on signal efficacy is a well-studied selective force. Still, very little is known on its impact on chemical signals. 2. Here, we took a broad, phylogenetic comparative approach to test for a relationship between animals` signal chemistry and properties of their natural environment. Our study focused on lizards from the Lacertidae family. 3. We sampled 64 species across three continents and determined the lipophilic composition of their glandular signalling secretions using gas chromatography-mass spectrometry. For each species, an array of environmental variables of high temporal and spatial resolution was obtained from climate databases. 4. Species varied considerably in the overall richness (number of constituents) of their secretions, as well as in the relative contribution of the major chemical compound classes. Signal richness and the relative contribution of the respective compounds exhibited little evidence of phylogenetic relatedness, suggesting that chemical signals may change very rapidly. Neither insularity nor substrate use affected chemical signal composition, however, we found a strong statistical relationship between the chemistry of the lizards` secretions and aspects of the thermal and hydric environment they inhabit. 5. Species from `xeric` milieus contained high proportions of stable fatty acid esters and high molecular weight alcohols in their glandular secretions, which likely increase the persistence of secretion scent-marks. In contrast, species inhabiting `mesic` environments produced secretions of a high chemical richness comprising high levels of aldehydes and low molecular weight alcohols. This chemical mix probably creates a volatile-rich signal that can be used for long-distance airborne communication. 6. We argue that the observed variation in signal design results from differential natural selection, optimizing signal efficacy under contrasting environmental conditions.

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New and additional distribution records are given for 12 amphibian, 25 lizard, one amphisbaenian, and five snake taxa from the Cape Province, South Africa. Some of the new records represent large range extensions, whereas others fill in gaps or confirm the occurrence of taxa in the region.

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The taxonomic status, distribution and ecology of the herpetofauna of the Orange Free State are discussed, based on the examination of 10 096 specimens housed in various southern African museums. The majority of specimens were collected during the years 1972 - 1978 and 1983 - 1992, and are housed at the National Museum, Bloemfontein. A total of 25 amphibian and 95 reptilian (one translocated species) forms have been determined as occurring in the Orange Free State, 12 (three amphibians, nine reptiles) of which are new (or recently published) records for the province. An additional 10 amphibian and 28 reptilian forms have been determined as occurring nearby but extralimitally to the O.F.S., and several of these forms are expected to occur in the province. New distributional records have resulted in the amendment of the ranges of several species. Detailed taxonomic data on new material, including rare species, have been given. Some problem areas in the taxonomy of O.F.S. taxa have been higlighted. An analysis of habit utilization indicated that 84,0% of amphibians and 61,1% of reptiles are terricolous, whereas up to 21,5% of reptiles are rupicolous. The majority of snakes (72,2%) are terrestrial in habits, but 13,9% are fossorial. More than half of all lizards (52,8%) are terrestrial, although 34,6% are rupicolous. A total of six amphibian and 27 reptile forms utilize inactive termitaria as a microhabitat, including several basically terrestrial forms. Snake forms were particularly well represented in termitaria, 60,6% of all forms known from the O.F.S. having been recorded from inactive termitaria. General features of the ecology of O.F.S. amphibians and reptiles have also been discussed. The biogeographical analysis indicated that O.F.S. amphibian forms can be classified into one of nine range clusters (common patterns of distribution), and reptiles into 13 such cluster groups. By testing these classifications by means of a transect through the northern O.F.S. (from eastern to western borders), it was determined that a fairly distinct east-west subtraction of amphibian and reptilian species and subspecies occurs in the O.F.S. Clustering of range boundaries and high species and subspecies diversity at the western and eastern ends of the transect zone suggest dynamic biogeographical situations occurring in those areas - the western group being associated with the transition from grassland to bushveld, and the eastern group associated with the transition from Highveld Grassland to Drakensberg Mountains. The general eastern and western groupings of taxa appear to be associated with the cooler, wetter and mountainous east vs the warmer, drier and lowerlying west, respectively. Despite a great deal of collecting having been conducted in the O.F.S. from 1972 to 1992, an analysis of the number of taxa collected in each quarter-degree unit in `the O.F.S. indicated that additional collecting would be required in order to conduct effectively a mathematically-based biogeographical analysis.

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A checklist of the lizards of the Cape Province, South Africa is presented. A total of 143 species and subspecies is recognized. The taxonomic status of no less than 84 (59,1%) of these has changed since the last review of the Cape lizards by FitzSimons (1943). Comments on the distribution and taxonomic status of problematic groups are included.

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An annotated check list of the herpetofauna of the Tsitsikamma National Parks is given. A total of 38 species, comprising 6 chelonians (2 tortoises, 4 sea turtles), 8 lizards, 11 snakes and 13 amphibians have been collected within the parks. The diversity of the Tsitsikamma Coastal National Park is greater than that of the Tsitsikamma Forest National Park. This is due to a number of factors, including more intensive collecting, greater area and habitat diversity, and the presence of 5 marine species. The parks are important reserves for a number of species endemic to the southern coastal region, including Bradypodion damaranum, Cordylus coeruleopunctatus, Breviceps fuscus and Afrixalus knysnae. An appendix lists a number of additional species that can still be expected to occur within the parks.

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A phylogenetic-comparative approach was used to assess and refine existing secondary structure models for a frequently studied region of the mitochondrial encoded large subunit (16S) rRNA in two large lizard lineages within the Scincomorpha, namely the Scincidae and the Lacertidae. Potential pairings and mutual information were analyzed to identify site interactions present within each lineage and provide consensus secondary structures. Many of the interactions proposed by previous models were supported, but several refinements were possible. The consensus structures allowed a detailed analysis of rRNA sequence evolution. Phylogenetic trees were inferred from Bayesian analyses of all sites, and the topologies used for maximum likelihood estimation of sequence evolution parameters. Assigning gamma-distributed relative rate categories to all interacting sites that were homologous between lineages revealed substantial differences between helices. In both lineages, sites within helix G2 were mostly conserved, while those within helix E18 evolved rapidly. Clear evidence of substantial site-specific rate variation (covarion-like evolution) was also detected, although this was not strongly associated with specific helices. This study, in conjunction with comparable findings on different, higher-level taxa, supports the ubiquitous nature of site-specific rate variation in this gene and justifies the incorporation of covarion models in phylogenetic inference.

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The phenotype of an individual has often been used as the descriminating factor in distinguishing species. However, with the advent of more precise molecular techniques, the genotype of species is increasingly being used as the preferred method in taxonomic classifications. Many taxa have recently been demonstrated to be incongruent in terms of their genetic and morphological groupings, and this may due to the influence that the environment may have on the morphological and functional aspects of a species. Selective pressures often act upon the performance of a species within a particular habitat first, and then selection for the morphological characters that allow for optimal performance occurs. Should genetically disparate species inhabit a particular environment, convergence in morphologies and performance may evolve. Historically, lizard species descriptions were based primarily on external morphologies, and thus misclassfication of species may have occurred due to mistakenly grouping species with convergent morphologies together. In the current dissertation, the links between morphology, performance capacities, diet and behaviour is explored in comparison to the environment and genetic relationships of southern African lacertid lizards. The performance capacities and associated morphological traits were expected to be more closely linked with the environment, and not closely linked with genetic relationships. To investigate these expectations, a multidisciplinary approach was taken, and genetic, morphological and performance analyses were done and compared with dietary behavioural and environmental analyses. In the first chapter, the link between habitat openness and the lizard bauplans is investigated and the presence of convergent morphologies within this group of lizards is uncovered. These convergences are shown to have resulted in misclassification of two lacertid species, and taxonomic revisions within the family are discussed. The second chapter explores the link between performance and associated morphological traits, and the dietary composition of the members of the Nucras genus. The third chapter identifies the link between the predator escape strategies employed by the members of the Meroles genus, and their morphologies and performance capacities. The fourth chapter explores the intraspecific, inter-population differences in morphologies and investigates the link between the morphological groupings and the population genetic groupings within Pedioplanis lineoocellata. The final chapter identifies whether adaptation to a novel habitat can occur over a relatively short period of time, and the morphological traits, functional aspects, and population genetic structure is investigated in conjunction with environmental analyses of vegetation and substrate between the populations of Meroles knoxii. It was concluded that the morphological and functional aspects of the southern African lacertid lizards are more closely related to the environment, particularly the microhabitat structure, than to their genetic relationships, and that future work using this group of lizards should involve a multidisplinary approach as different selective pressures are playing a role in shaping the morphologies and performance capacities of these lizards, compared to those that are acting upon the genotypes of the lizards.

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Eremiadinae, one of three subfamilies of Lacertidae, are distributed throughout Asia and Africa. Previous phylogenetic studies suggested that one of the main groups of Eremiadinae (the Ethiopian clade) consist of two clades with predominately East-African and South-African distribution. Yet, especially the latter one, which includes the genera Pedioplanis, Meroles, Ichnotropis, Tropidosaura and Australolacerta, was not well supported in the molecular phylogenetic analysis. In this study, we analysed the phylogenetic relationships among the genera of the ‘South African clade’ to assess whether this group actually forms a highly supported clade and to address questions concerning the monophyly of the genera. We sequenced sections of the widely used mitochondrial genes coding for 16S rRNA, 12S rRNA and cytochrome b (altogether 2045 bp) as well as the nuclear genes c-mos, RAG-1, PRLR, KIF24, EXPH5 and RAG-2 (altogether 4473 bp). The combined data set increased the support values for several nodes considerably. Yet, the relationships among five major lineages within the ‘South African clade’ are not clearly resolved even with this large data set. We interpret this as a ‘hard polytomy’ due to fast radiation within the South African lacertids. The combined tree based on nine marker genes provides strong support for the ‘South African Clade’ and its sister group relationship with the ‘East African Clade’. Our results confirm the genus Tropidosaura as a monophylum, while Ichnotropis is paraphyletic in our trees: Ichnotropis squamulosa appears more closely related to Meroles than to Ichnotropis capensis. Furthermore, the monophyly of Meroles is questionable as well. Based on our results, I. squamulosa should be transferred from Ichnotropis into the genus Meroles. Also, the two species of Australolacerta (A. australis and A. rupicola) are very distantly related and the genus is perhaps paraphyletic, too. Finally we propose a phylogeographical scenario in the context of palaeoclimatic data and compare it with a previously postulated hypothesis.

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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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While global variation in taxonomic diversity is strongly linked to latitude, the extent to which morphological disparity follows geographical gradients is less well known. We estimated patterns of lineage diversification, morphological disparity and rates of phenotypic evolution in the Old World lizard family Lacertidae, which displays a nearly inverse latitudinal diversity gradient with decreasing species richness towards the tropics. We found that lacertids exhibit relatively constant rates of lineage accumulation over time, although the majority of morphological variation appears to have originated during recent divergence events, resulting in increased partitioning of disparity within subclades. Among subclades, tropical arboreal taxa exhibited the fastest rates of shape change while temperate European taxa were the slowest, resulting in an inverse relationship between latitudinal diversity and rates of phenotypic evolution. This pattern demonstrates a compelling counterexample to the ecological opportunity theory of diversification, suggesting an uncoupling of the processes generating species diversity and morphological differentiation across spatial scales.

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the Lacertidae is one of the most diverse and widespread lizard families throughout Eurasia and Africa. Several studies so far have attempted to unravel the phylogeny of Lacertidae using morphological and mole- cular data. However, the intra-family relationships remain unclear. in an effort to explore the phylogenetic relationships within the family Lacertidae, a concatenated dataset of 5727 bp from six genes (two nuclear and four mitochondrial) and 40 genera was assembled based on GenBank database. Phylogenetic inference analy- ses were conducted using Maximum Parsimony (MP), Bayesian inference (Bi) and Maximum Likelihood (ML), revealing that even a combined dataset of both mitochondrial and nuclear genes is not able to resolve the phylogenetic relationships of the Lacertidae family under the tribe level.

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The dangers of helminth infestations for lizards, particularly infestations with nematodes und cestodes, are reported. Infection routes, diagnoses, und treatments are described.

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Aim To map and assess the richness patterns of reptiles (and included groups: amphisbaenians, crocodiles, lizards, snakes and turtles) in Africa, quantify the overlap in species richness of reptiles (and included groups) with the other terrestrial vertebrate classes, investigate the environmental correlates underlying these patterns, and evaluate the role of range size on richness patterns. Location Africa. Methods We assembled a data set of distributions of all African reptile species. We tested the spatial congruence of reptile richness with that of amphibians, birds and mammals. We further tested the relative importance of temperature, precipitation, elevation range and net primary productivity for species richness over two spatial scales (ecoregions and 1° grids). We arranged reptile and vertebrate groups into range-size quartiles in order to evaluate the role of range size in producing richness patterns. Results Reptile, amphibian, bird and mammal richness are largely congruent (r = 0.79–0.86) and respond similarly to environmental variables (mainly productivity and precipitation). Ecoregion size accounts for more variation in the richness of reptiles than in that of other groups. Lizard distributions are distinct with several areas of high species richness where other vertebrate groups (including snakes) are species-poor, especially in arid ecoregions. Habitat heterogeneity is the best predictor of narrow-ranging species, but remains relatively important in explaining lizard richness even for species with large range sizes. Main conclusions Reptile richness varies with similar environmental variables as the other vertebrates in Africa, reflecting the disproportionate influence of snakes on reptile richness, a result of their large ranges. Richness gradients of narrow-ranged vertebrates differ from those of widespread taxa, which may demonstrate different centres of endemism for reptile subclades in Africa. Lizard richness varies mostly with habitat heterogeneity independent of range size, which suggests that the difference in response of lizards is due to their ecological characteristics. These results, over two spatial scales and multiple range-size quartiles, allow us to reliably interpret the influence of environmental variables on patterns of reptile richness and congruency.

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The family Lacertidae encompasses more than 250 species distributed in the Palearctis, Ethiopis and Orientalis. Lacertids have been subjected in the past to several morphological and molecular studies to establish their phylogeny. However, the problems of convergent adaptation in morphology and of excessively variable molecular markers have hampered the establishment of well supported deeper phylogenetic relationships. Particularly the adaptations to xeric environments have often been used to establish a scenario for the origin and radiation of major lineages within lacertids. Here we present a molecular phylogenetic study based on two nuclear marker genes and representatives of 37 lacertid genera and distinct species groups (as in the case of the collective genus Lacerta). Roughly 1600 bp of the nuclear rag1 and c-mos genes were sequenced and analyzed. While the results provide good support to the hitherto suggested main subfamilies of Gallotiinae (Gallotia and Psammodromus), Eremiainae and Lacertinae [Harris, D.J., Arnold, E.N., Thomas, R.H., 1998. Relationships of lacertid lizards (Reptilia: Lacertidae) estimated from mitochondrial DNA sequences and morphology. Proc. R. Soc. Lond. B 265, 1939–1948], they also suggest unexpected relationships. In particular, the oriental genus Takydromus, previously considered the sister-group to the three subfamilies, is nested within Lacertinae. Moreover, the genera within the Eremiainae are further divided into two groups, roughly corresponding to their respective geographical distributions in the Ethiopian and the Saharo-Eurasian ranges. The results support an independent origin of adaptations to xeric conditions in different subfamilies. The relationships within the subfamily Lacertinae could not be resolved with the markers used. The species groups of the collective genus Lacerta show a bush-like topology in the inferred Bayesian tree, suggesting rapid radiation. The composition of the subfamilies Eremiainae and Lacertinae as well as their phylogeography are discussed.

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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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Point distribution data were used to evaluate the biogeographical influence of the arid Tankwa Karoo Basin on the distribution of reptiles in the south-western districts of South Africa. Under-representation of the Tankwa Karoo in the dataset required an additional field survey of this region. Prior to the survey, available records from the Tankwa Karoo Basin represented only 13 reptile species. A total of 36 species (24 lizards, nine snakes, three chelonians) was recorded during our survey of this area. Turnover across the Basin is high, species richness is lower than in surrounding mountainous areas and there are no species endemic to the area. The Tankwa Karoo Basin acts as a dispersal barrier for many reptile species occurring in the surrounding more mesic areas. At the same time, the ranges of a number of typical northern, arid-adapted species extend southward along the Tankwa plains. A number of species range extensions in the region are reported.

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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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While the stability of sex chromosomes is widely accepted in viviparous mammals and birds, ectothermic vertebrates are still largely viewed as having frequent turnovers in sex determining systems. Frequent changes in sex determining systems in ectotherms could be problematic for field ecological studies as well as for breeding programs, as molecular sexing across a phylogenetically widespread spectrum of ectothermic vertebrates would not be possible. However, we recently documented that sex determining systems in three important reptile lineages (caenophidian snakes, iguanas, and lacertid lizards) are in fact highly conserved. 2.We applied a new molecular procedure to identify sex within each of these three lineages (encompassing altogether around 4,000 species, i.e. nearly 50% of the recent species of reptiles). This technique uses quantitative PCR (qPCR) to compare copy numbers of genes specific for their respective Z (in caenophidian snakes and lacertids) and X (in iguanas) chromosomes between male and female genomes. The DNA samples required can be collected relatively non-invasively. Unlike molecular sexing based on repetitive elements, this technique can be easily applied to previously unstudied species of these lineages, as the number of copies of protein coding genes linked to the differentiated sex chromosomes is evolutionary highly conserved in each. 3.We suggest that qPCR-based molecular sexing using the comparison of gene copy number is a practical choice for non-model species of caenophidian snakes, iguanas and lacertids. Morever, it should also soon be available for other reptile lineages with differentiated sex chromosomes.

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The staggering phenotypic variation among organisms and the striking fit between an organism`s morphology and its environment have fascinated naturalists for centuries. Darwin`s publication of `On the origin of species` was the first to offer an explanation for the apparently perfect form-function relationship. During the past century overly enthousiastic evolutionary biologists interpreted any direct link between an organism`s morphology and ecology as evidence for the theory of evolution by natural selection. However, for morphological variation to be considered adaptive it is necessary to explicitly test how this variation translates into the variation in ecologically relevant performance traits, which in turn translates into ecological (and fitness) variation. Nowadays, performance- based ecomorphological approaches are typically used to test the adaptive nature of phenotypic variation in order to provide a better understanding of the selective pressures operating on organisms. Using an ecomorphological approach, lacertid lizards have been used extensively to test whether and how they are adapted to their environment. The majority of these studies have mainly included European species, leaving African species underrepresented. This is suprising from an evolutionary viewpoint. Compared to European lacertids, African lacertid lizard clades are older and more speciose. Also, lacertid lizard communities on the African continent are more complex than the ones in Europe (i.e. comprising 7-8 species versus 2-3 species). In this talk, we will focus on the phenotypic divergence among African clades and the link with the variation in performance and ecology, and explicitly compare these results to results on European lacertids.

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Shape variation in the vestibular system is often linked to microhabitat structure and locomotor performance. Highly circular and orthogonal semicircular canal pairs are linked to higher motion sensitivity. Here, we use 3D geometric morphometrics to investigate shape variation in the vestibular system within lacertid lizards and its relationship to balance control. We found that lacertids living in complex microhabitats possess narrow but longer vestibular systems, an S-shaped anterior canal, a straightened lateral canal and a short common crus. However, lacertids specialized for simple microhabitats (open areas) possess wider but shorter vestibular systems, more circular anterior and lateral canals, and a longer common crus. Contrary to our expectations, species living in simple microhabitats possess more anatomical adaptations that enhance the sensitivity of their vestibular system. This suggests that species inhabiting open areas may benefit from increased sensitivity given that they are potentially more visibile to predators and have lower shelter availability. Finally, the wider shape of the vestibular system of the open area species may be linked to a wider and potentially flattened skull, which may be related to sand-diving or prey hardness.

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We surveyed six protected areas along the Wild Coast of the Eastern Cape, South Africa, to determine general herpetofaunal diversity as well as the representation of species of special conservation concern. Visual encounter survey methods and standard Y-shape trap arrays were used to conduct surveys from 2011 to 2013. A total of 59 species (22 amphibians and 37 reptiles) were recorded. A number of previously unknown populations of threatened species and one potential novel species were discovered in these protected areas, and the known ranges of several other species were extended. A total of 243 quarter-degree grid-cell unit records were documented, of which 90 (23% amphibians and 50% reptiles) represented the first records for the area. Amphibian and reptile diversity increased along the coast and a number of species of conservation concern were well represented in current protected areas. Our study provides a comprehensive amphibian and reptile checklist for an under-sampled region and highlights the importance of baseline data for improving conservation management. Conservation implications: Small protected areas play an important role in conserving a number of threatened herpetofaunal species along the Wild Coast. The region is currently under significant and increasing pressure from anthropogenic-induced environmental degradation, which affects biodiversity and subsequently the local inhabitants. The information presented here represents an important baseline for future conservation management.