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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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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 complete catalogue is provided for the type specimens of lacertid lizards in the herpetological collection of the Zoological Museum, Berlin, as of December, 1993. The collection contains a total of 514 type specimens, representing 63 taxa, of which 42 are currently regarded as valid at the specific or subspecific level. Types representing an additional four taxa appear to have been lost from the collection. The collections are especially rich in African lacertid types and in historically significant specimens collected early in the Nineteenth Century by Pallas, Eversmann, and Hemprich & Ehrenberg. Also present are the type series of many subspecies of Podarcis lilfordi and P. pityusensis described by Eisentraut.

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The Koanaka South locality of western Ngamiland, Botswana, is a Plio-Pleistocene cave deposit. While this deposit has produced numerous reptile and amphibian fossils, a lack of comparative osteological material from the region has hampered taxonomic diagnosis, particularly below the level of family. In addition, the lack of a published account of the modern herpetofauna from the area prevents documenting how the reptile and amphibian faunas have changed over the last two million years. A collecting trip to Koanaka South in the winter dry season (19–30 June 2008) resulted in the collection of 38 specimens of nine species belonging to seven squamate families (Agamidae, Chamaeleonidae, Gekkonidae, Lacertidae, Scincidae, Viperidae). Two additional species, the gekkonid Ptenopus garrulous and the elapid snake Dendroaspis polylepis are documented from sound and sight records, respectively, and one additional lacertid, Heliobolus lugubris, is vouchered by older museum material. No amphibians were observed during the survey. Nine taxa are explicitly reported from the Koanaka Hills or in quarter degree square 2021 Aa for the first time and a range extension and size record are reported for Pedioplanis namaquensis and Ichnotropis squamulosa, respectively. Based on collections made in the surrounding quarter degree square (2021 Aa), as well as published range maps, we provide a list of 39 additional reptiles and amphibians expected, but not yet documented, in the vicinity of Koanaka South.

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A list of 60 species of amphibians and reptiles found during a six-week survey in western Zambia is presented. Two species of amphibians are newly reported for Zambia: Amietia chapini and an undescribed species of Tomopterna, previously known to occur in the Democratic Republic of Congo and in Namibia, respectively. Some of the material collected could not be confidently identified to species level because of the taxonomic complexity and uncertainty of some groups (e.g., Phrynobatrachus, Ptychadena), even with the use of DNA barcoding. This list is a small contribution to the growing knowledge of Zambian and African herpetology.

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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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Reptiles are gonochorists (with the exception of a few parthenogenetic lizards and a single snake) and have relatively few young. Hermaphroditism is absent, possibly due to the existence of internal fertilisation and the complexity of the associated genitalia. Environmental sex determination (ESD) is known in 2 lizards, most chelonians and all crocodilians so far studied. Its significance is obscure. Previous explanations, based on presumed selective advantages of sex-related hatchling size differences, seem improbable due to both groups slow attainment of sexual maturity. It is proposed that a more likely advantage is the ability to produce highly skewed sex ratios by behavioural selection for nesting site choice. Both orders are the most fecund reptiles and suffer high juvenile mortality. The direction of sex determination differs between crocodilians and chelonians (high incubation temperatures produce males and females, respectively.) The evolution of heteromorphic sex chromosomes has occurred independently many times in squamates, and in one chelonian, and this may be correlated with the undesirability of ESD in short-lived species with low fecundity. Parental care is almost completely absent, reaching its highest expression among crocodilians and certain anguid lizards. All young, including those of species showing parental care, are precocial and immediately feed exogenously. The absence of altricial young is possibly due to the difficulty of food handling between adults and young. Viviparity is found only among squamates, where it has evolved independently on numerous occasions. Its evolution is usually associated with cold climates, although certain other traits (e.g. the possession of venom and/or the existence of maternal brooding) may serve as pre-adaptations. Analysis of the effects of size and phylogeny on patterns of co-variation in certain squamate life-history traits reveals that although many variables scale allometrically with body size, significant variation in clutch size and age at maturity remains at order, family and generic level. The size and mass of females and their clutches may vary between populations and years, reflecting phenotypic plasticity to proximate environmental factors. Relative Clutch Mass (RCM — the ratio of female body mass to clutch mass) is correlated with foraging mode and predator escape tactics in lizards (but not in snakes) and with reproductive mode (i.e. viviparity) in snakes.

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This review summarises the current status of our knowledge of Angolan reptile diversity, and places it into a historical context of understanding and growth. It is compared and contrasted with known diversity in adjacent regions to allow insight into taxonomic status and biogeographic patterns. Over 67% of Angolan reptiles were described by the end of the nineteenth century. Studies stagnated dur- ing the twentieth century but have increased in the last decade. At least 278 reptiles are currently known, but numerous new discoveries have been made during recent surveys, and many novelties await description. Although lizard and snake diversity is currently almost equal, most new discoveries occur in lizards, particularly geckos and lacertids. Poorly known Angolan reptiles and others from adjacent regions that may occur in the country are highlighted. Most endemic Angolan reptiles are lizards and are associated with the escarpment and southwest arid region. Identification of reptile diversity hotspots are resolving but require targeted surveys for their delimitation and to enable protection. These include the Kaokoveld Centre of Endemism, Angolan Escarpment and the Congo forests of the north. The fauna of Angola remains poorly known and under-appreciated, but it is already evident that it forms an important centre of African reptile diversity and endemism.

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A fourteen-month marking/recapture study of the sympatric lacertids Ichnotropis squamulosa and I. capensis (Sauria.Lacertidae) was carried out at Zimunya township near Umtali. This confirmed that these lizards have staggered life cycles and that individuals rarely live for more than 12 months, thus reducing competition for food between similar-sized lizards of the two species.

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This review looks at available literature on the reptiles (including terrapins, tortoises, lizards, amphisbaenians, crocodiles) and amphibians of the Four Corners trans-frontier area, which covers both wetland and dryland habitats. The zoogeography of these groups is outlined. This is followed by an annotated list of the 178 species recorded to date. Particular species ands sites of conservation interest are briefly outlined. The herpetofauna of the Four Corners area is a comparatively well studied group, although the Hwange District in northwestern Zimbabwe has received the most attention.

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We discuss three aspects of the thermal biology of lacertid lizards. First, we provide an overview of the available data on field body temperatures (Tb), the thermal sensitivity of various performance functions and selected body temperatures in different species of lacertid lizards. We also briefly summarise information on the mechanisms of thermoregulation. Second, we discuss recent developments to estimate the »precision« of thermoregulation, and the contribution of distinct behavioural mechanisms. Finally, we revise available evidence for the existence of evolutionary adjustments of thermal characteristics in lacertid lizards. Existing studies have mainly dealt with within- and among-species differences in thermoregulatory behaviour (selected temperatures) and thermal physiology of adults (optimal temperatures, heating rates). Available data provide only limited evidence for clear-cut evolutionary shifts in thermal physiology characteristics along climatic gradients.

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Angola`s herpetofauna has been neglected for many years, but recent surveys have revealed unknown diversity and a consequent increase in the number of species recorded for the country. Most historical Angola surveys focused on the northeastern and southwestern parts of the country, with the southeast , now comprising the Kuando-Kubango Province, neglected. To address this gap a series of rapid biodiversity surveys of the upper Cubango-Okavango basin were conducted from 2012‒2015. This report presents the results of these surveys, together with a herpetological checklist of current and historical records for the Angolan drainage of the Cubango, Cuito, and Cuando Rivers. In summary 111 species are known from the region, comprising 38 snakes, 32 lizards, five chelonians, a single crocodile and 34 amphibians. The Cubango is the most western catchment and has the greatest herpetofaunal diversity (54 species). This is a reflection of both its easier access, and thus greatest number of historical records, and also the greater habitat and topographical diversity associated with the rocky headwaters. As a result of these surveys, five new species records were added to the Cubango catchment, 17 to the Cuito catchment, and nine to the Cuando catchment. Seven of the records for the eastern catchments, including three for the Cuito and four for the Cuando, were also new for Angola. Resumo.—A herpetofauna de Angola foi negligenciada durante muitos anos, mas vários levantamentos realizados recentemente revelaram uma diversidade desconhecia e um consequente aumento no número de espécies registadas para o país. A maior parte dos levantamentos históricos realizados em Angola focaram-se no nordeste e sudoeste do país, sendo o sudeste, que agora abrange a província do Kuando-Kubango, bastante negligenciado. Para preencher esta lacuna, foram realizados vários levantamentos de biodiversidade na bacia superior do Cubango-Okavango entre 2012 e 2016. Neste relatório são apresentados os resultados destes levantamentos, bem como uma lista de registos herpetológicos recentes e históricos para as bacias dos rios Cubango, Cuito, e Cuando. Resumidamente, conhecem-se 111 espécies para a região, incluindo 39 espécies de cobras, 32 espécies de lagartos, 5 espécies de quelónios, apenas um crocodilo, e 34 espécies de anfíbios. A bacia hidrográfica do Cubango é a que está localizada mais a oeste, e tem a maior diversidade de herpetofauna (54 espécies). Isto reflecte por um lado a sua maior acessibilidade, e consequentemente um maior número de registos históricos, e ainda a maior diversidade topográfica e de habitat, associada às nascentes rochosas. Como resultado destes levantamentos, foram adicionadas cinco novas espécies à bacia do Cubango, 17 à do Cuito, e nove à do Cuando. Sete dos registos para as bacias a este, incluindo trois para o Cuito e quatro para o Cuando, são também novos registos para Angola.

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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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Molecular phylogenetic analyses of southern African lacertid lizards (Eremiadini) using mitochondrial and nuclear markers revealed two examples of generic assignments incompatible with monophyletic clades. Australolacerta Arnold 1989, a genus endemic to South Africa and to which two isolated species have been referred, is paraphyletic at the generic level. In addition, the species Ichnotropis squamulosa Peters 1854 was found to be embedded within the genus Meroles. To resolve the paraphyly in Australolacerta we erect a new genus, Vhembelacerta Edwards, Branch, Herrel, Vanhooydonck, Measey, & Tolley, gen. nov., to accommodate Lacerta rupicola FitzSimons 1933. To maintain a monophyletic Ichnotropis Peters 1854, Ichnotropis squamulosa Peters 1854 is transferred to Meroles Gray 1838, now named Meroles squamulosus comb. nov. Where necessary the genera affected by these actions are re-characterized.

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Survival, in part, depends on an individual`s ability to evade predators. In desert regions some lizard species have evolved head-first sand-diving strategies to escape predators. To facilitate this behaviour, a distinctive head morphology that facilitates sand-diving has evolved. This specialised head morphology may, however, come at a cost to other ecologically relevant functions, particularly bite force. Here, we investigated the relationship between morphology and function in a southern African lacertid lizard genus, Meroles, which consists of eight species that utilise different escape strategies, including sand-diving and running for cover. It was hypothesized that the specialised head morphology of diving species would negatively affect bite force capacity. We found that species from each escape strategy category differed significantly in head shape, but not bite force performance. A phylogenetic tree of the genus was constructed using two mitochondrial and two nuclear genes, and we conducted phylogenetic comparative analyses. One aspect of the head shape differed between the escape strategies once phylogeny was taken into account. We found that bite force may have co-evolved with head morphology, but that there was no trade-off between biting capacity and escape strategy in Meroles.

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Convergent evolution can explain similarity in morphology between species, due to selection on a fitness-enhancing phenotype in response to local environmental conditions. As selective pressures on body morphology may be strong, these have confounded our understanding of the evolutionary relationships between species. Within the speciose African radiation of lacertid lizards (Eremiadini), some species occupy a narrow habitat range (e.g. open habitat, cluttered habitat, strictly rupicolous, or strictly psammophilic), which may exert strong selective pressures on lizard body morphology. Here we show that the overall body plan is unrelated to shared ancestry in the African radiation of Eremiadini, but is instead coupled to habitat use. Comprehensive Bayesian and likelihood phylogenies using multiple representatives from all genera (2 nuclear, 2 mitochondrial markers) show that morphologically convergent species thought to represent sister taxa within the same genus are distantly related evolutionary lineages (Ichnotropis squamulosa and Ichnotropis spp.; Australolacerta rupicola and A. australis). Hierarchical clustering and multivariate analysis of morphological characters suggest that body, and head, width and height (stockiness), all of which are ecologically relevant with respect to movement through habitat, are similar between the genetically distant species. Our data show that convergence in morphology, due to adaptation to similar environments, has confounded the assignment of species leading to misidentification of the taxonomic position of I. squamulosa and the Australolacerta species.

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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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Climatic conditions changing over time and space shape the evolution of organisms at multiple levels, including temperate lizards in the family Lacertidae. Here we reconstruct a dated phylogenetic tree of 262 lacertid species based on a supermatrix relying on novel phylogenomic datasets and fossil calibrations. Diversification of lacertids was accompanied by an increasing disparity among occupied bioclimatic niches, especially in the last 10 Ma, during a period of progressive global cooling. Temperate species also underwent a genome- wide slowdown in molecular substitution rates compared to tropical and desert-adapted lacertids. Evaporative water loss and preferred temperature are correlated with bioclimatic parameters, indicating physiological adaptations to climate. Tropical, but also some popu- lations of cool-adapted species experience maximum temperatures close to their preferred temperatures. We hypothesize these species-specific physiological preferences may con- stitute a handicap to prevail under rapid global warming, and contribute to explaining local lizard extinctions in cool and humid climates.

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The reproductive cycle of the common rough-scaled lizard, Ichnotropis squamulosa from southern Africa was studied from a histological examination of gonads. The smallest reproductively active male and female I. squamulosa measured 47 mm and 58 mm SVL, respectively. Males began (spermiogenesis) sperm production and females began yolk deposition in February (summer). The reproductive cycle of I. squamulosa differs from that of other lacertid lizards from southern Africa which typically begin sperm production in late winter or early spring concurrent with the onset of yolk deposition. This difference in timing of reproduction may enhance survival of I. squamulosa as its young appear in spring by which time neonates of other lacertid species are larger and have different dietary preferences.

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An annotated checklist of indigenous and potentially indigenous Namibian terrestrial, aquatic and marine reptiles is presented. The purpose is to serve as an interim description of Namibian reptile diversity, to establish a taxonomic and biogeographical baseline, and as a preliminary review of the conservation status of Namibian reptiles. Two hundred and forty species of indigenous reptiles are presently known to occur in Namibia. These species comprise an array of approximately 265 described (but not always recognized) taxa, several of which are probably unwarranted. Species accounts are presented for all these species. Four accounts are for new species currently being described. Nineteen species have not yet been recorded from Namibia, but are expected to (accounts given) and another 6 species are less likely to occur (no accounts given). Full accounts are given for the 17 species which have been formally recorded in the past, but the lack of recent evidence suggests that the species is now locally extinct, the original report erroneous, or the species’ occurred as vagrants. Four additional species had been included on various published lists in the past, but have never been formally documented, no specimens are known to exist, and it is unlikely that the species would occur today even as vagrants (no accounts given). In total, 276 species-accounts are presented. Each account cites the original reference and type locality for each taxon, and a short description of the Namibian distribution. Emphasis is placed on Namibian and international legal and conservation status. Eighty-five species (33%) were found to be of local conservation concern. Gaps in knowledge (e.g. taxonomy, biogeography, and conservation status), where future research should be directed, are noted.

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The herpetofauna of the southern Kalahari has mixed affinities, as this area lies on a rainfall gradient in a critical area where a transition between the arid south-west and the moister north-east takes place. As the variation in substrate type is relatively limited, the effect of the rainfall gradient appears to influence and determine the range limits of many taxa in both directions, resulting in an area in which of 55 recorded reptiles, 11 western taxa overlap or form a parapatric zone with 25 eastern taxa, while the remaining taxa are endemic or wideranging.

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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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Namibia is mostly an arid and semi-arid country with a high number of reptile and fewer amphibian species. We review the herpetological literature dealing with Namibian species over the past fifty years, and provide up-to-date amphibian and reptile accounts using a widely accepted taxonomy and nomenclature. We critically discuss species accounts, draw attention to the historical development of species inventories for the country, and indicate species endemism for Namibia and the Namib Desert. In Namibia, the lizard families Gekkonidae, Lacertidae, and Scincidae have undergone adaptive radiations and are species-rich. This also applies to the snake family Psammophiidae. Areas of herpetological research that have received most attention are systematics (with its disciplines faunistics (area inventories), taxonomy, and phylogeny), ecology, and physiology. The former is indicative of early stages of herpetological research such as area inventories and the subsequent analyzes of the collections. The latter two were largely enabled by (1) species highly adapted to life in the hyper-arid Namib Desert, and (2) by the accessibility of these species in the Namib Desert through the infrastructure provided by the Gobabeb Research and Training Center. The majority of the eco-physiological research has focused on three highly psammophilus, diurnal lizard species; Meroles anchietae, M. cuneirostris, and Gerrhosaurus skoogi, whilst diverse geckos form the basis of eco-morphological studies. The concentration of research localities around cities and the Gobabeb Research and Training Center is characteristic for opportunistic research. Geographic centers of herpetological research have been the central Namib Desert (i.e. Gobabeb), and areas around Swakopmund and Windhoek. Extensive parts of Namibia remain barely touched. Herpetological publication frequency has been approximately the same since its beginning in the early 1800`s until the 1970`s. The period between 1986 and 2003 experienced a remarkable increase of publication activity that has slightly subsided around 2004 and picked up again in recent years. Recent conservation related studies investigate the impact of overgrazing with land degradation and water related issues such as canals and hydroelectric dam projects on herpetological communities. In the near future the impact of mining, especially Uranium mining in the Namib Desert, and the effects of climate change with the predicted drying and warming will demand increased attention. Advances in biotechnology with ever-increasing amounts of data and decreasing cost have and will progressively enable advances in traditional disciplines like taxonomy, phylogeny, and systematics. Additionally, these technologies will increasingly empower the newer disciplines of molecular ecology and conservation biology in Namibia. Annotated, updated species checklists highlight Namibian and Namib diversity and endemicity, and also direct researchers to the numerous taxonomic problems that still confound full understanding of the region`s herpetofauna.

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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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We discuss seasonal variation in thermoregulatory behavior and its consequences on body temperature for 12 species of diurnal lizards in the southern Kalahari semidesert of Africa and also evaluate several methods of attempting to document thermoregulatory behavior using a descriptive data base. Lizards vary time of activity among seasons, which limits the variation in ambient conditions actually experienced. Ground-dwelling lizards and probably arboreal lizards move nonrandomly with respect to sun and shade; thus the percentage of lizards in sun in inversely proportional to air temperature. Arboreal lizards shift to higher perches at midday in summer and to logs or ground in winter thus decreasing and increasing incident heat loads, respectively. Both juveniles and adults of 3 species, only juveniles of 2 species, and only adults in 1 species are active in winter: both adults and juveniles of 6 species brumate [= hibernate]. Mean body temperature (T`b) varies within days and among months and is positively correlated with corresponding mean air temperature (T`a) in almost all species. Nonetheless, correlation and regression analysis suggests that thermoregulatory behaviors reduce the impact of variations in ambient conditions on Kalahari lizards. The mean T`b of different species reflect evolutionary relationships. In summer, mean T`b is proportional to the percentage of lizards in sun and with the tendency of lizards to be active only in summer. Thus, lizards with inferred low optimal temperatures are active during more months of the year.

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Desert lizards are typically either widely foraging or sit-and-wait predators, and these foraging modes are correlated with major differences in ecology. Foraging mode is related to the type of prey eaten by lizards. Widely foraging lizards in the Kalahari desert, the Western Australian desert, and the North American desert generally eat more prey that are sedentary, unpredictably distributed, and clumped (e.g., termites) or that are large and inaccessible (inactive scorpions) than do sit-and-wait lizards. In contrast, sit-and-wait lizards eat more prey that are active. Foraging mode also appears to influence the types of predators that in turn eat the lizards. For example, a sit-and-wait snake eats predominately widely foraging lizards. Crossovers in foraging mode thus exist between trophic levels. Widely foraging lizards may also encounter predators more frequently, as suggested by analyses of relative tail lengths; but tail break frequencies are ambiguous. Daily maintenance energetic expenditures of widely foraging lizards appear to be about 1.3-1.5 times greater than those of sit-and-wait lizards in the same habitats, but gross food gains are about 1.3-2.1 times greater. Widely foraging species also have lower relative clutch volumes, apparently in response to enhanced risks of predation. Foraging mode within one species varies with changes in food availability. Physiology, morphology, and risk of predation might generally restrict the flexibility of foraging mode. Because foraging mode constrains numerous important aspects of ecology, any general model of foraging velocity must be complex.

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The performance of ectotherms integrated over time depends in part on the position and shape of the distribution of body temperatures (Tb) experienced during activity. For several complementary reasons, physiological ecologists have long expected that Tb distributions during activity should have a long left tail (left‐skewed), but only infrequently have they quantified the magnitude and direction of Tb skewness in nature. To evaluate whether left‐skewed Tb distributions are general for diurnal desert lizards, we compiled and analysed Tb (∑ = 9,023 temperatures) from our own prior studies of active desert lizards in three continents (25 species in Western Australia, 10 in the Kalahari Desert of Africa and 10 species in western North America). We gathered these data over several decades, using standardized techniques. Many species showed significantly left‐skewed Tb distributions, even when records were restricted to summer months. However, magnitudes of skewness were always small, such that mean Tb were never more than 1°C lower than median Tb. The significance of Tb skewness was sensitive to sample size, and power tests reinforced this sensitivity. The magnitude of skewness was not obviously related to phylogeny, desert, body size or median body temperature. Moreover, a formal phylogenetic analysis is inappropriate because geography and phylogeny are confounded (i.e. are highly collinear). Skewness might be limited if lizards pre‐warm inside retreats before emerging in the morning, emerge only when operative temperatures are high enough to speed warming to activity Tb, or if cold lizards are especially wary and difficult to spot or catch. Telemetry studies may help evaluate these possibilities.

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We discuss seasonal variation in thermoregulatory behavior and its consequences on body temperature for 12 species of diurnal lizards in the southern Kalahari semidesert of Africa and also evaluate several methods of attempting to document thermoregulatory behavior using a descriptive data base. Lizards vary time of activity among seasons, which limits the variation in ambient conditions actually experienced. Ground-dwelling lizards and probably arboreal lizards move nonrandomly with respect to sun and shade; thus the percentage of lizards in sun is inversely proportional to air temperature. Arboreal lizards shift to higher perches at midday in summer and to logs or ground in winter thus decreasing and increasing incident heat loads, respectively. Both juveniles and adults of 3 species, only juveniles of 2 species, and only adults in I species are active in winter: both adults and juveniles of 6 species brumate [= hibernate]. Mean body temperature (T,) varies within days and among months and is positively correlated with corresponding mean air temperature (T,) in almost all species. Nonetheless, correlation and regression analysis suggests that thermoregulatory behaviors reduce the impact of variations in ambient conditions on Kalahari lizards. The mean Tb of different species reflect evolutionary relationships. In summer, mean T i s proportional to the percentage of lizards in sun and with the tendency of lizards to be active only in summer. Thus, lizards with inferred low optimal temperatures are active during more months of the year.

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A survey of the distribution, status and general ecology of amphibians, reptiles and mammals was undertaken on the Nylsvley Nature Reserve, Transvaal from mid-1974 to mid-1977 as part of the South African Savanna Ecosystem Project. A total of 18 frog, 3 tortoise, 1 terrapin, 23 lizard, 1 amphisbaenid, 29 snake and 62 mammal species were recorded on the Reserve. As new additions continued to be made late in the survey, it is clear that the checklist is not yet complete.

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The staggered life cycles of I. squamulosa and the related species I. capensis are ascribed by Broadley (1979) to avoidance of competition. This paper dicusses this theory in the light of size, temporal and spatial distribution of the two species. Discussions on clutch size, time of laying and incubation period are incorporated.

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This paper reports on and discusses the findings of a herpetofaunal survey of the San Sebastian Peninsula, Vilankulo, Mozambique. A total of 39 reptile and 20 amphibian species were recorded including new records for Mozambique, range extensions and taxa previously considered endemic to the Bazaruto Archipelago.

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In Chapter 11 population structure was discussed in relation to reproduction. Reproduction is a major factor in changes in density, which in turn influence reproductive rates; this is one of the best known density-dependent phenomena. The density of a population reflects the interaction of communal physical and biotic elements. This chapter describes some examples of the relationships between community structure, exogenous factors and fluctuations in density.

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Ngamiland is one of the most remote regions in Botswana, and its herpetofauna is largely under-surveyed. This study documents the herpetofauna of the Koanaka Hills (KH) in Ngamiland in 2009 following extensive fire destruction and compares it to the pre-fire herpetofauna collected in 2008. We also provide new records for the region for three amphibian and six reptile species, and document vouchers for two taxa that were sighted but not collected in 2008. During 2009, 14 reptile and three amphibian species were collected, bringing the total number of confirmed herpetofaunal taxa near the KH to three amphibian and 19 reptile species. For seven species this is the first published occurrence in quarter degree square 2021 Aa. Analyses measuring changes in the KH herpetofauna following the fire are inconclusive due to differences in collection effort and weather conditions. However, these data suggest that fire impact was minimal.

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Several specimens of different genera of Lacertid lizards were collected during a 4-week-trip into the Limpopo Province of South Africa. Depending on their habitat members of the different species occurred within different reptile species assemblages. On the Soutpansberg specimens of Nucras intertexta were recorded in unusual habitat and a genetic study shall resolve their systematic position. No Lacertids were recorded in the high altitudes of the Blouberg and Wolkberg, which is most probably attributed to sampling artifacts.

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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 present work constitutes an historical atlas of all known bibliographic records of amphib- ians and reptiles of Angola. It is the first attempt to compile in a single document all the records scattered through hundreds of publications, published from the first half of the nineteenth century to the present day, and provide a critical taxonomic revision of the herpetofauna of the country. An introductory text discusses the Angolan socio-political and physiographic landscape, the history of herpetological research in the country, and the diversity, distribution and endemism of Angolan her- petofauna. It also provides a summary of the conservation concerns surrounding the herpetological fauna. For each taxon noted in the literature we provide a detailed taxonomic account, including data on the original description, its IUCN assessment status, global distribution, georeferenced records for each known occurrence in Angola (accompanied by a point locality map), and taxo- nomic and distributional notes. A synoptic list of all documented Angolan amphibian and reptile species is provided as are lists of taxa previously erroneously assigned to the Angolan fauna. We recognize 117 species of frogs and 278 species of reptiles as occurring in Angola, although many of these represent species complexes or are currently recognized under names of convenience pending taxonomic evaluation. In one instance we provide a replacement name, Trachylepis monardi nom. nov., to deal with an instance of secondary homonymy. The Atlas is intended to be a working reference for both current research and conservation planning, as well as a catalyst for future work.The interest shown by specialists in the study of Angolan specimens dates back more than one hundred years. Since the nineteenth century, books and papers have been published on the topic as the result of these investigations. The first major bibliographic reference about the Angolan herpetofauna, Herpétologie d’Angola et du Congo by José Vicente Barbosa du Bocage, dates from 1895. Many researchers and publications followed, greatly enriching the scientific bibliography on the topic. However, the scattered nature of the published works, as well as the dearth of available specimens from earlier times, has made it difficult for researchers, scholars or curious amateurs to access to this information. Because of these difficulties, and to facilitate the access to available data on the Angolan herpetofauna, the Ministry of Environment, through its National Institute of Biodiversity and Conservation Areas, decided to present, in a single volume, all the available scientific records published so far on the diversity of amphibians and reptiles. Such a task, which has its basis in the National Strategy and Action Plan for Biodiversity and Conservation Areas of Angola, was dependent upon the helpful collaboration of important international partners. The present Atlas will be of inestimable assistance to the study of the Natural History of Ango- la, not only because of its standardized taxonomic and geographical accounts with distribution maps for all of the amphibians and reptiles known in Angola, but also because of its competent approach to the physiography, climate, biomes, historical herpetological research in Angola, conservation, and other topics. The thoughtful way the book is arranged, with straightforward text, clear tables and interesting figures, makes it easy for even laymen to read and understand. At 501 pages long, profusely documented and richly illustrated, this Atlas provides a grand guided tour through the diversity of the Angolan herpetofauna, from the most remote and spectac- ular places of the country. Through mountains and escarpments, plains and valleys, savannas and dense forests, rivers and streams, lakes and lagoons, this work encompasses the entire country, aking us on an enlightening tour of knowledge. The methodical labor and persistence of the specialists who produced the present work, ensure that it not only contributes to scientific history, through its compilation of research already completed, but also suggests future directions for researchers and scholars devoted to the topic. Further, this substantial volume will also inform the national authorities with respect to environ- ment protection and conservation policies. Given all this, one can see that the present work, reflecting the contributions of the men and women who created it, is destined to become a standard reference to the scientific literature of the country, especially in regard to this part of its fauna. The quality of the scientific information poured into the following pages certainly qualifies the authors of this accurate work as leading herpetologists and places them among the important researchers to have served Angola in the course of its scientific history.

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13 species of the genera Aporosaura, Meroles, Pedioplanis, and Heliobolus horn Namibia and additionally Pedioplanis burcheUi from the Republic of South-Africa have been investigated proteinelectrophoretically concerning 14 genetic loci. Pedioplanis and Meroles turned out to be sister groups, Heliobolus and Aporosaura are standing further apart. The su bgenera of Meroles (Meroles s. str. and Saurites) could not be parted distinctly. The morphological correspondence between Aporosaura and Saurites has been interpreted as convergent adaptions to their habitat.

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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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Aim Temperature influences most components of animal ecology and life history – but what kind of temperature? Physiologists usually examine the influence of body temperatures, while biogeographers and macroecologists tend to focus on environmental temperatures. We aim to examine the relationship between these two measures, to determine the factors that affect lizard body temperatures and to test the effect of both temperature measures on lizard life history. Location World-wide. Methods We used a large (861 species) global dataset of lizard body temperatures, and the mean annual temperatures across their geographic ranges to examine the relationships between body and mean annual temperatures.We then examined factors influencing body temperatures, and tested for the influence of both on ecological and life-history traits while accounting for the influence of shared ancestry. Results Body temperatures and mean annual temperatures are uncorrelated. However, accounting for activity time (nocturnal species have low body temperatures), use of space (fossorial and semi-aquatic species are ‘colder’), insularity (mainland species are ‘hotter’) and phylogeny, the two temperatures are positively correlated. High body temperatures are only associated with larger hatchlings and increased rates of biomass production. Annual temperatures are positively correlated with clutch frequency and annual longevity, and negatively correlated with clutch size, age at first reproduction and longevity. Main conclusions Lizards with low body temperatures do not seem to have ‘slower’ life-history attributes than species with high body temperatures. The longer seasons prevalent in warm regions, and physiological processes that operate while lizards are inactive (but warm enough), make environmental temperatures better predictors of lizard life-history variation than body temperatures. This surprisingly greater effect of environmental temperatures on lizard life histories hints that global warming may have a profound influence on lizard ecology and evolution.

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Aim We provide a new quantitative analysis of lizard reproductive ecology. Comparative studies of lizard reproduction to date have usually considered life-history components separately. Instead, we examine the rate of production (productivity hereafter) calculated as the total mass of offspring produced in a year. We test whether productivity is influenced by proxies of adult mortality rates such as insularity and fossorial habits, by measures of temperature such as environmental and body temperatures, mode of reproduction and activity times, and by environmental productivity and diet. We further examine whether low productivity is linked to high extinction risk. Location World-wide. Methods We assembled a database containing 551 lizard species, their phylogenetic relationships and multiple life history and ecological variables from the literature. We use phylogenetically informed statistical models to estimate the factors related to lizard productivity. Results Some, but not all, predictions of metabolic and life-history theories are supported. When analysed separately, clutch size, relative clutch mass and brood frequency are poorly correlated with body mass, but their product – productivity – is well correlated with mass. The allometry of productivity scales similarly to metabolic rate, suggesting that a constant fraction of assimilated energy is allocated to production irrespective of body size. Island species were less productive than continental species.Mass-specific productivity was positively correlated with environmental temperature, but not with body temperature. Viviparous lizards were less productive than egg-laying species. Diet and primary productivity were not associated with productivity in any model. Other effects, including lower productivity of fossorial, nocturnal and active foraging species were confounded with phylogeny. Productivity was not lower in species at risk of extinction. Main conclusions Our analyses show the value of focusing on the rate of annual biomass production (productivity), and generally supported associations between productivity and environmental temperature, factors that affect mortality and the number of broods a lizard can produce in a year, but not with measures of body temperature, environmental productivity or diet.

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From 12 to 18 species of desert lizards occur in ecologic sympatry on 10 study areas in the Kalahari desert of southern Africa. The number of species of diurnal lizards is similar to the number in the North American deserts, while the nocturnal component of the saurofauna is more comparable to that occurring in the Australian deserts. The between-habitat component of species density is similar in the American and the Kalahari deserts, but is markedly greater in the Australian desert. A variety of climatic and vegetational statistics are examined for the 10 areas, and correlations with lizard species density are discussed.

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The herpetofauna of Mozambique remains poorly documented despite several recent surveys. This paper presents additional distribution records for a number of species from Mozambique, based on recent field excursions and older material at the Ditsong National Museum of Natural History. The new records suggest that a number of taxa are more widely distributed in southern Mozambique than is currently known while the additional material suggests that the taxonomy of some species requires further research.

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The herpetofauna of Mozambique remains poorly documented despite recent surveys. We present here the first report on the herpetofauna occurring in Parque Nacional de Banhine in Gaza Province. Four chelonian, 13 snake, one amphisbaenid, 16 lizard and 15 frog species were recorded in the park, while an additional six snake, five lizard and two frog taxa have been recorded in close proximity and probably also occur in the park. Numerous range extensions are recorded, and these are discussed in the light of our present knowledge of the distribution of herpetofauna in Mozambique.

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The herpetofauna of southern Africa is currently receiving an increased amount of attention. The Zoological Society of Southern Africa held a symposium on herpetology and ichthyology in 1975, the proceedings of which have been published in Zoologica Africana, and no less than 17 papers dealt specifically with research carried out recently on southern African amphibians and reptiles. Our aim in this chapter, therefore, can be no more than to sketch the present state of knowledge and thinking in a rapidly changing field.

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Jchnotropis squamulosa is a terrestial lizard of arid and semiarid savannas in Africa. The species is characterized by a remarkable short life period of eight to nine months. Studies on biometrical aspects, growth, reproduction biology, annual rhythms and behaviour of this lizard were carried out within the framework of a population field study in the Northem Province of South Africa. Data on body length and body mass development suggest, that 1. squamulosa is a rather quickly growing species. The growing rate was constant during the whole investigation time and was not influenced by the periods of sexually mature, mating and egg production. Annual patterns of life like hatching, ontogenesis or egg development are well adapted to the optimal periods of climatic conditions and food supply during the year. The sexes of 1. squamulosa differ in their rate of caudal autotomy and in some biometrical data. The species mating behaviour is described for the first time. The results of the field study are discussed in detail under aspects of adaption strategies to the remarkable short life cycle of 1. squamulosa.

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In this paper, the evolution and ecology of directional asymmetry (DA) during the developmental trajectory (DT) is compared with that of its product, morphological DA (MDA). DT and MDA are calculated for two bilateral morphological scale characters of lizards, the number of subdigital lamellae beneath the fourth toe in 10 agamid and 28 lacertid taxa, and the number of rows of ventral scales in 12 lacertid taxa. MDA, the subtraction between left and right sides (classical measure of DA), is functional in adult animals. Results confirm the hypodiesis that, in DT, the regression parameters a (constant) and b (regression slope) of counts on the right side with those on the left describe a developmental process. No phylogenetic or environmental effects were observed on a and b, but analyses considering both a and b together show non-random phyletic patterns. Independent analyses deduced the same ancestral DT in Agamidae and Lacertidae. In Lacertidae, distance between pairs of taxa in a + b (standardized values) correlates positively with die phylogenetic distance between taxa. Phyletic trends in MDA are indirect, and due to the link of MDA with a + b. The MDA of species is more dissimilar in sympatry than in allopatry. The phyletic trends suggest evolution of DT, while die association of MDA witii sympatry suggests that ecological pressures shape MDA in adult animals. Evolution of DT is independent from tiiat of its product, MDA–adaptive determinism defines the result of, but not the mechanistic process of, development. Deterministic environmental processes define MDA, and deterministic evolutionary processes define the interactive result of a and b, but not each separately. According to circumstances, different DTs produce similar or different MDA, and a particular DT can produce different MDAs.

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The spatial distribution of a woodland lizard community was studied in April and July 1980, and January 1981. This study showed that various species of reptiles were microhabitat-substrate-specific, hence confirming earlier work on reptiles. Microhabitat niche overlap values and niche diversity were generally low, and a discussion on factors that determine ecological structure and the role of spatial organization in reptile community ecology is given.

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The food type and foraging habits of African lizards of the genera Mabuya, Agama, Ichnotropis and Lygodactylus from Dambwa Forest Reserve, Livingstone, Zambia, are documented. The bulk of the diet of these lizards consists of termites and ants. Since these lizards feed mainly on small colonial insects, the added advantage to the community of having lizards of different ages and sizes, within and between species, feeding on different size prey, an aspect that reduces competition for food in many other lizards, does not exist. Thus in the absence of this phenomenon, lizards in this community were found to co-exist and avoid competitive exclusion by foraging in different micro-habitats and exhibiting behavioral differences with respect to procuring food.

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The Regional Office for Southern Africa of IUCN (IUCN-ROSA), in conjunction with the Canadian International Development Agency (CIDA), initiated the Zambezi Basin Wetlands Conservation and Resource Utilisation Project (ZBWCRUP) in 1996. This project is aimed at ensuring wise use of natural resources of the wetlands of the Zambezi Basin, focussing in particular on four project sites (the Barotse floodplains in western Zambia, the floodplains and swamps of the Chobe/Caprivi region of Namibia and Botswana, the wetlands of the Lower Shire in southern Malawi and Mozambique, and the Zambezi Delta in Mozambique). One of the project activities is to assess the importance of biodiversity from a conservation perspective, both for the four wetland areas and for the wetlands of the Zambezi Basin as a whole. The Zambezi Society and the Biodiversity Foundation for Africa were invited to carry out this component as Phase 1 of larger project. This volume, the resulting report, consists of a compilation, evaluation and assessment of existing published technical information on the biodiversity of these wetlands. An annotated bibliography containing 979 references on organismal and ecological biodiversity was compiled, and an edited version of 942 references (excluding those not strictly concerning biodiversity) is presented in an electronic database format. A series of 59 keywords, covering geographical area, biological group and subject area, has been used to facilitate search and retrieval. Coverage in the literature is very uneven, both for geographical area and biological group. The best documented areas are the Kafue Flats, the Chobe/Caprivi area and Lake Kariba. Barotseland and the Zambezi Delta are particularly poorly documented given their size. The best covered groups are plants, large mammals, birds and fish. Information on small mammals and most invertebrate groups is very limited. Knowledge on taxonomy of the various groups is generally good, with the exception of many invertebrate groups where even a rough indication of numbers of species present is not available. Checklists have been prepared for some groups and for some wetland areas, but there are gaps which preclude, at this stage, a detailed comparison of biodiversity between wetlands and across the basin. Literature on the ecological role, function and productivity of wetland organisms is very scant for the area. Although there are a number of species restricted to the wetlands of the Zambezi Basin in a number of different groups, detailed listings are not yet available except for large mammals, birds, reptiles, amphibians and fish. The lechwe antelope (with three subspecies endemic to the floodplains of the proto-Upper Zambezi) and the Wattled Crane (seasonally with 90% of the world population in the wetlands of the Zambezi Basin) are possibly the best “flagship species” for conservation of the wetlands, encompassing most of the major concerns and issues. The clear division of the Zambezi Basin into three physical and biogeographical sections ! Upper, Middle and Lower ! is described. Biological composition differs greatly between the Upper and Middle/Lower sections, and is thought to be a result of comparatively recent river capture of the proto-Upper Zambezi (which originally included the Bangweulu swamps, Kafue, Kavango and Okavango) by the more recent Middle Zambezi. The instability and biological youth of many of the Zambezi wetlands, particularly the swamps, is discussed. This is shown to be a major factor in their relatively homogeneous composition across the basin. The floodplains of the proto-Upper Zambezi are seen as having been more stable over recent evolutionary time. They appear to be more species-rich and hold a greater number of species of limited distribution than the swamps. Although perhaps less heavily modified than many river basins in Africa, the Zambezi has been greatly changed in its middle section by large impoundments at Kariba and Cabora Bassa, as well as on the Kafue at Itezhi-Tezhi and on the upper reaches of tributaries in Zimbabwe. Biodiversity composition has been greatly modified in both obvious and indirect ways through the creation of new habitats, facilitation of distribution of species, and through reduced flooding. The effects of flood control in the Zambezi Delta have given rise to conservation concerns, but documentation is hampered by lack of baseline information. However, on the Upper Zambezi any changes in hydrology, extent of wetlands and biodiversity are principally a result of climatic cycles rather than the effects of human activities. Expertise in organismal biodiversity, both regional and international, was compiled into a database with 135 persons cited. This database, by no means exhaustive, is also presented in an electronic format with keywords to enable rapid searching. The major groups covered are plants and birds, and most of the expertise cited is based in Zimbabwe or South Africa. Expertise in many invertebrate and microscopic groups is dangerously limited. The important role of amateur naturalists is pointed out, particularly for birds, large mammals and butterflies. Twenty four recommendations are given. Some are general and apply equally to the whole basin, whilst some cover research topics. It is suggested that a basin-wide perspective is required for conservation, and to achieve this a series of vegetation maps with a common legend are required, more attention needs to be paid to old floodplains and dambos, and detailed reviews of selected biological groups should be carried out. Sites of particular conservation interest need to be identified, as do those wetland species in need of active conservation measures. A series of monitoring sites should ideally be set up across the basin which can be used to detect change due to human impact. The final general recommendation is to make biodiversity information more accessible through appropriate publications and media releases. On the research side, investigation is required into wetland ecological processes and resilience, the effects of river impoundment on the wetlands of the Zambezi Basin, and the potential for use of aquatic organisms as indicator species. Specific recommendations, some of which could be addressed by ZWCRUP, are a revision and publication of the annotated bibliography incorporating a more concise review, and a series of activities related to the four sub-project sites. These include biodiversity inventory of selected groups, production of compatible vegetation maps, identification of sites of conservation interest, and an assessment of the effects of land use change on biodiversity. The site-specific activities are spelled out in detail.

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Evolutionary changes in foraging style are often believed to require concurrent changes in a complex suite of morphological, physiological, behavioural and life-history traits. In lizards, species from families with a predominantly sit-and-wait foraging style tend to be more stocky and robust, with larger heads and mouths than species belonging to actively foraging families. Here, we test whether morphology and foraging behaviour show similar patterns of association within the family Lacertidae. We also examine the association of bite force abilities with morphology and foraging behaviour. Lacertid lizards exhibit considerable interspecific variation in foraging indices, and we found some evidence for a covariation between foraging style and body shape. However, the observed relationships are not always in line with the predictions. Also, the significance of the relationships varies with the evolutionary model used. Our results challenge the idea that foraging style is evolutionarily conservative and invariably associated with particular morphologies. It appears that the flexibility of foraging mode and its morphological correlates varies among lizard taxa.