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

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

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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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Data relating to the Sandveld lizards (Nucras) occurring in Namibia, southwest Africa are reviewed. In particular, we investigated records of N. holubi, a chiefly southeastern African species, and attempted to identify recently collected material that could not be assigned to any species currently recognized in Namibia. A phylogenetic analysis of Nucras based on three mitochondrial markers revealed a deep divergence between Namibian Nucras holubi and two presumably conspecific clades from Limpopo Province, South Africa. In addition, the coloration pattern and scalation of the Namibian material differ from those of the eastern forms, supporting its recognition as a separate species. The name Nucras damarana Parker, 1936, long relegated to the synonymy of N. holubi, is here resurrected for this apparently endemic northern Namibian species. Nucras damarana is restricted to the Kunene, Omusati, Oshikati, Kavango, and Otjozondjupa regions of north-central Namibia. A distinctive specimen of Nucras from near Ruacana in the Kunene Region was identified as allied to Nucras broadleyi, a species recently described from southwestern Angola, on the basis of genetic data, although it differs substantially in color pattern. With the addition of N. aff. broadleyi and the resurrected N. damarana to its fauna, as well as the removal of N. holubi from the nation’s species list, four species of Nucras are confirmed to be present in Namibia. Although the conservation status of N. damarana, N. tessellata, and N. intertexta is Least Concern, the uncertain taxonomic status of N. aff. broadleyi precludes a meaningful threat assessment.

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New informations concerning systematical questions within the family Lacertidae, which were published during the last year, are presented.

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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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Numerous new distribution records are given for 19 amphibian, 3 tortoise, 32 lizard, and 15 snake species and subspecies in the Cape Province, particularly in the eastern and central karroid regions. Many species are shown to have much wider distributions than previously believed. The importance of the mountains of the inland escarpment as a refugium for temperate species, the presence of isolated populations of western arid species in the karroid valleys of the northern Cape Fold Mountains, and the possible vicariant effects caused by sea level fluctuations on species inhabiting the southern Cape coastal plain, are briefly discussed.

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The results of a survey of the reptiles and amphibians of the Addo Elephant National Park (AENP) are presented. A total of 49 species, comprising 16 amphibians, 14 lizards, 15 snakes and 4 chelonians, occur in the AENP. Observations on the biology and distribution of these species in the AENP are given, and the relative composition and diversity is compared with the herpetofauna of the surrounding eastern Cape and the more distant Kruger National Park. The zoogeographic affinities of the AENP herpetofauna are similar to those of the surrounding eastern Cape (i.e. Cape Temperate 46,9, Temperate- Transitional 16,3, Eastern Tropical Transitional 10,2, Western Tropical Transitional 8,2, Tropical East Coast Littoral 2,0 and Temperate Wideranging 16,3). Resource partitioning among the AENP herpetofauna is discussed and the conservation status of the species summarised. A list of species that may still be collected within the AENP is included.

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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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The functional characteristics of prey items (such as hardness and evasiveness) have been linked with cranial morphology and performance in vertebrates. In lizards particularly, species with more robust crania generally feed on harder prey items and possess a greater bite force, whereas those that prey on evasive prey typically have longer snouts. However, the link between dietary niche breadth, morphology, and performance has not been explicitly investigated in lizards. The southern African genus Nucras was used to investigate this link because the species exhibit differing niche breadth values and dietary compositions. A phylogeny for the genus was established using mitochondrial and nuclear markers, and morphological clusters were identified. Dietary data of five Nucras species, as reported previously, were used in correlation analyses between cranial shape (quantified using geometric morphometrics) and dietary niche breadth, and the proportion of hard prey taken and bite force capacity. Dietary niche breadth and the proportion of hard prey eaten were significantly related to cranial shape, although not once phylogeny was accounted for using a phylogenetic generalized least squares regression. The proportion of evasive prey eaten was a significant predictor of forelimb length when phylogeny was taken into account. We conclude that, in Nucras, the percentage of evasive prey taken co-evolves with forelimb morphology, and dietary niche breadth co-evolves with cranial shape. However, although head width is correlated with the proportion of hard prey eaten, this appears to be the result of shared ancestry rather than adaptive evolution.

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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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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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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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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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Sandveld lizards (genus Nucras) are widespread in southern Africa, but are generally secretive and poorly known. We examined 385 preserved specimens from five species of Nucras collected over a broad time span (104 years) and a geographic area covering most of South Africa and Swaziland. We had three main objectives: to test for sexual size dimorphism, to quantify male and female reproductive cycles, and to determine diet. In addition, we examined the importance of scorpions in the diet of Nucras based on previous studies reporting an unusually high incidence of scorpions in the diet of Kalahari N. tessellata. Males of all species except N. lalandii had significantly larger heads than females of the same body size, although females had significantly greater snout–vent length than males in three of the five species examined. The general reproductive pattern was for females to contain vitellogenic eggs during late spring and early summer. No females simultaneously contained oviductal and vitellogenic eggs, which suggests that females produce only one clutch per season. Clutch size was unrelated to female body size in all species examined. Female follicle volume generally coincided with male testicular volume, indicating for the most part synchronized reproductive cycles between the sexes. Testis volume was generally highest during spring–early summer, with only N. holubi showing a second peak in autumn. We recorded 15 arthropod orders in the diet of Nucras. All species feed on invertebrates, primarily insects, and, to a lesser degree, spiders and centipedes. Termites, grasshoppers, and beetles both numerically and volumetrically dominated their diet. We found no evidence that scorpions form a major part of the diet of any of these five species of Nucras, including N. tessellata from biomes outside the Kalahari Desert.

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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.