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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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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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Brief presentstion of the South African Sandveld Lizard Nucras holubi und its discoverer EMIL HOLUB.

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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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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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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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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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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.