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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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A large number of reptiles from the Central African Republic (CAR) were collected during recent surveys conducted over six years (October 1990 to June 1996) and deposited at the Paris Natural History Museum (MNHN). This large collection of 4873 specimens comprises 86 terrapins and tortois- es, five crocodiles, 1814 lizards, 38 amphisbaenids and 2930 snakes, totalling 183 species from 78 local- ities within the CAR. A total of 62 taxa were recorded for the first time in the CAR, the occurrence of numerous others was confirmed, and the known distribution of several taxa is greatly extended. Based on this material and an additional six species known to occur in, or immediately adjacent to, the coun- try from other sources, we present a biogeographical analysis of the 189 species of reptiles in the CAR.

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In March 1990 Poromera fordii was seen on the ground of a rainforest near Dehane Cameroun.

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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 reptiles of Mt Nlonako, a mountain at the southeastern edge of the Cameroon mountain range (`Dorsale camerounaise`), were inventoried continually over a six year period from 1998 to 2004. This area encompasses 150 km2 of lowland, submontane and montane rainforest with an elevation up to 1,825 m. Accounts of 89 species are provided based on collected and photo-documented material. This inventory proved Mt Nlonako to be the most species rich single-locality area in reptilian fauna in Africa. With 63 snake species Mt Nlonako exhibits the greatest number of species in Africa and possibly worldwide. Analysis showed the reptilian species composition to be most similar within Cameroon with that of Korup National Park followed by the Dja Faunal Reserve in the south. Relative to the snake composition the Korup NP and the Dimonika region in Congo-Brazzaville show the highest resemblance. In an African context the reptile fauna of Mt Nlonako is characterized by species which occur in both West and Central Africa as opposed to the mountain`s amphibian species which more closely resemble Central African fauna. The high species richness and endemicity is discussed from a paleoclimatic perspective. Conservation status and threats to the reptiles are noted.

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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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A lizard specimen recently collected from Gabon can not be assigned to any known species for the country. It is identified as Ichnotropis bivittata, a lacertid previouslnot reported for the country. The specimen is described in details and compared to related species. An older specimen examined by Boulenger (1921) was collected in the same area but not identified as from Gabon since the country was not always with the same borders and under the name `Congo français`.

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In the framework of a broad study of the vertebrate diversity at Monte Alen National Park (Río Muni, Equatorial Guinea), we identified 16 families, 47 genera, and 65 species of reptiles and seven families, 29 genera, and 56 species of amphibians. 21 species of reptiles and four species of amphibians represent new records for the Río Muni region. We present the preliminary inventory of the herpetofauna as well as some ecological comments. Monte Alén is considered one of the most diverse protected areas in central Africa from a herpetological standpoint.

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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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This paper presents the composition of the lizard fauna of Maringa-Lopori-Wamba landscape in the western portion of the central Congo basin in the Democratic Republic of the Congo and its weak similarity with the lizard fauna of Gaboon and Ituri faunal areas. It also fills a gap of knowledge in a region where no previous research on Sauria has been undertaken and signals the presence of Leptosiaphos hylophilus and Lygodactylus n. sp. The paper mentions the finding of a subspecies of Gastropholis echinata. These data are important since collected for the first time in a spot where no herpetological research on lizards has previously been undertaken.

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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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Data deficiency in tropical regions is still a major problem in herpetofaunistic research. During the last few years we conducted several field expeditions to Central Africa, including the Congo Basin. In 2012 we visited four sites in the westernmost part of the Democratic Republic of the Congo. These included the Mangroves National Park in the region of the Congo River estuary as well as the Mayombe region characterized by low mountains covered by rainforest, all north of the Congo River, and an additional site south of the Congo River with savannah habitats. Remarkably, no recent herpetological research was done in this part of the country. We surveyed a wide spectrum of habitats including mangroves, savannah, forests, village surroundings and agricultural sites. Approximately 22 species (or representatives of species complexes) of amphibian and 23 species of reptile have been recorded.

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We provide an updated, commented list of the reptiles of Gabon, with their occurrence in the country’s protected areas, national parks and reserves. This list is part of a book describing the current status of knowledge of the biodiversity of Gabon, including detailed descriptions and abundant illustrations of its ecosystems and protected areas.

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A synthesis of the current state-of-knowledge of herpetofaunal diversity in the recently-created Gabonese national park system is provided. A provisional reptile list is currently available for only four of the 13 parks: Crystal Mountains, Loango, Lopé and Moukalaba-Doudou. Representation of endemic, near-endemic and legally-protected Gabonese reptiles in the parks is analyzed. Only one of the seven (near-)endemic species is recorded from a national park. Among non-park sites, Mount Iboundji and the Rabi oil field (including Lake Divangui) were shown to be of high herpetological interest, enough to constitute adequate biodiversity sanctuaries. Enforcement and revision of protection laws, especially regarding sea turtles, softshell turtles and crocodiles, is urgently needed.

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Based on our field surveys and literature records, we provide a preliminary list of the reptile fauna of the Chaillu Mountains, central-southern Gabon. The list includes 50 species: 2 crocodilians (Crocodylus cataphractus and Osteolaemus tetraspis), 2 chelonians (Pelusios castaneus and Kinixys erosa), 14 lacertilians (including a Hemidactylus new to Science) and 32 ophidians (including a Typhlopid new to Science, and the first record for Gabon of the freshwater snake Hydraethiops laevis), representing 15 families and 39 genera. The list is accompanied by local vernacular names, biological and ethnozoological data.

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We performed surveys at several lower elevation sites surrounding Mt. Kupe, a mountain at the southern edge of the Cameroonian Highlands. This work resulted in the sampling of 48 species, including 38 amphibian and 10 reptile species. By combining our data with prior survey results from higher elevation zones, we produce a checklist of 108 species for the greater Mt. Kupe region including 72 frog species, 21 lizard species, and 15 species of snakes. Our work adds 30 species of frogs at lower elevations, many of which are associated with breeding in pools or ponds that are absent from the slopes of Mt. Kupe. We provide taxonomic accounts, including museum specimen data and associated molecular data, for all species encountered. Finally, we compare the levels of biodiversity of Mt. Kupe to other regions, discuss biogeographic ties to other montane systems, and note current conservation threats.

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Includes bibliographical references and index. Introduction. List of localities. New genus. List of new species and type localities. Preliminary note on the distribution of African lizards. Note on the distribution of African turtles -- Testudinata. Testudinae. Kinixys Bell. Pelomedusidae. Pelusios Wagler. Pelomedusa Wagler -- Loricata (Crocodilia). Crocodylidae. Crocodylus Laurenti. Osteoblepharon, new genus. Ecological notes on Congo crocodiles -- Squamata. Lacertilia. Geckonidae. Gonatodes Fitzinger. Hemidactylus Cuvier. Lygodactylus Gray. Agamidae. Agama Daudin. Varanidae. Varanus Merrem. Lacertidae. Lacerta Linnaeus. Bedriagaia Boulenger. Algiroides Fitzinger. Ichnotropis Peters. Eremias Wiegmann. Holaspis Gray. Gerrhosauridae. Gerrhosaurus Wiegmann. Scincidae. Mabuya Fitzinger. Lygosoma Gray. Ablepharus Fitzinger. Anelytropidae. Feylinia Gray. Chamaeleontidae. Chamaeleon Gronovius. Rhampholeon Günther -- Appendix A: Lists of the turtles, crocodiles, lizards, and chameleons of the rain forest and of the Sudanese subprovince -- Appendix B: Notes on the types of Hallowell`s West African species in the Academy of Natural Sciences of Philadelphia.