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Abstract The Equatorial African group of lacertids comprises nine species which share a number of derived features and appear to constitute a holophyletic assemblage. Revision of the group using morphological characters analyzed by parsimony and compatibility methods results in the following taxonomic changes: Lacerta jacksoni = Adolfus jacksoni, Lacerta echinata = Gastropholis echinata, Bedriagaia tropidopholis = Gastropholis tropidopholis, Bedriagaia moreavi = Gastropholis prasina, the latter species being validated and removed from the synonymy of Gastropholis vittata. Adolfus jacksoni has most features in common with the hypothetical ancestor of the group, while Holaspis guentheri and the species of Gastropholis are the most derived forms. Geographical variation in Adolfus alleni is described and what is known of the ecology of the Equatorial group summarized. Most are forest dwellers with the majority of the more primitive forms living on tree boles and among litter and timber on the forest floor (Adolfus jacksoni, A. africanus, A. vauereselli). Another, Holaspis guentheri, is confined to tree boles but glides between them, while the species of Gastropholis appear to be climbers in flimsy vegetation and Adolfus alleni is ground-dwelling above the tree line. Many of the morphological features characterizing these lizards appear to be functionally related to their particular habitats.

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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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Currently, four species of the lacertid lizard genus Adolfus are known from Central and East Africa. We sequenced up to 2825 bp of two mitochondrial [16S and cytochrome b (cyt b)] and two nuclear [(c-mos (oocyte maturation factor) and RAG1 (recombination activating gene 1)] genes from 41 samples of Adolfus (representing every species), two species each of Gastropholis and Holaspis, and in separate analyses combined these data with GenBank sequences of all other Eremiadini genera and four Lacertini outgroups. Data from DNA sequences were analysed with maximum parsimony (PAUP), maximum-likelihood (RAxML) and Bayesian inference (MrBayes) criteria. Results demonstrated that Adolfus is not monophyletic: Adolfus africanus (type species), Adolfus alleni, and Adolfus jacksoni are sister taxa, whereas Adolfus vauereselli and a new species from the Itombwe Plateau of Democratic Republic of the Congo are in a separate lineage. Holaspis and Gastropholis were recovered in separate clades. Based on these molecular data, relatively substantial sequence divergence, and multiple morphological differences, we describe a new genus of lacertid for the lineage including A. vauereselli and the new Itombwe species. The recognition of this new, endemic genus underscores the conservation importance of the Albertine Rift, especially the Itombwe Plateau, a unique region that is severely threatened by unchecked deforestation, mining, and poaching.

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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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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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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.

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This checklist records the 99 species of lizards known at present from Kenya, and which are divided amongst eight families: Gekkonidae 33 species, Agamidae seven, Chamaeleonidae 17, Scincidae 22, Lacertidae 12, Cordylidae five, Varanidae two, Amphisbaenidae one. Brief data on the distribution of all species is given, with some localities, details of habitat and (in some cases) status of subspecies. Some taxonomic notes on certain problematic species/genera are included, plus a brief discussion of the zoogeography of Kenya`s lizards, and a gazetteer of localities.

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The genus Adolfus Sternfeld, 1912 currently contains three species from Equatorial Africa. Two of these occur in widespread, low- to mid-elevation habitats, but Adolfus alleni is only known from four montane peaks (Aberdares, Mt. Kenya, Cherangani Hills, Mt. Elgon) in Kenya and Uganda. An integrative approach using 58 morphological characters and genetic analyses of mitochondrial (16S and cyt b) and nuclear (c-mos and RAG1) DNA sequence data revealed differences between these populations, and indicated that A. alleni is a complex of at least two cryptic species. Herein, we describe the populations from the Aberdares and Mount Elgon as a new species, and restrict A. alleni to Mount Kenya. This action underscores the importance of conservation strategies to protect these montane peaks, which may harbour additional, unique evolutionary lineages.