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

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Differences in surface structure (ober- hautchen) of body scales of lacertid lizards involve cell size, shape and surface profile, presence or absence of fine pitting, form of cell margins, and the occurrence of longitudinal ridges and pustular projections. Phylogenetic information indicates that the primitive pattern involved narrow strap-shaped cells, with low posteriorly overlapping edges and relatively smooth surfaces. Deviations from this condition produce a more sculptured surface and have developed many times, although subsequent overt reversals are uncommon. Like variations in scale shape, different patterns of dorsal body microornamentation appear to confer different and conflicting performance advantages. The primitive pattern may reduce friction during locomotion and also enhances dirt shedding, especially in ground-dwelling forms from moist habitats. However, this smooth microornamentation generates shine that may compromise cryptic coloration, especially when scales are large. Many derived features show correlation with such large scales and appear to suppress shine. They occur most frequently in forms from dry habitats or forms that climb in vegetation away from the ground, situations where dirt adhesion is less of a problem. Microornamentation differences involving other parts of the body and other squamate groups tend to corroborate this functional interpretation. Microornamentation features can develop on lineages in different orders and appear to act additively in reducing shine. In some cases different combinations may be optimal solutions in particular environments, but lineage effects, such as limited reversibility and different developmental proclivities, may also be important in their genesis. The fine pits often found on cell surfaces are unconnected with shine reduction, as they are smaller than the wavelengths of most visible light.

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In this paper we deal on the ultraviolet color (invisible to us): where we can find it, the capability of animals to see it and the advantages that this color perception offers to them. As the simplest way to detect it is the photography, we describe and review how to photograph the UV, as a result of 15 years of amateur experience, searching and testing nearly in complete blindness due to the lack of practical information about “how to do it”. We describe the different kinds of photography (chemical and digital); the cameras and objectives suitable (both astronomically expensive ones and cheap options); what are the best characteristics that the objectives should have for this purpose; the films suitable for their use in chemical photography; the different filters (current or discontinued) manufactured along the years; and the subtle combinations among the different materials to obtain pure UV photographs. This kind of scientific photography is mainly used in forensics, forgery detection, art dermatology and less in Natural History, despite the fact that a great part of animals see this color and use it in important questions of their biology as the social behavior, mate choice or the food search.

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The six floristic biomes in the Western Cape Province (W.C.P.), namely the Fynbos, Afromontane Forest, Thicket, Grassland, Nama and Succulent Karoo Biomes (Low and Rebelo, 1996), are not only diverse with regard to the variety of plant species and communities occurring there, but also contain a wide diversity of animal species, biogeographical zones, landscapes and natural features, both within the terrestrial and aquatic (freshwater and marine) context. In addition to the topographical diversity of the Cape Fold Mountains, the coastal zone and lowlands, and their transition into surrounding habitats, the W.C.P. experiences a wide climatic diversity too. These features have resulted in an extensive and complex diversity of habitat types which partly explain the rich biological diversity within the W.C.P. Past climatic changes on a global scale have also influenced ecological systems and processes within the W.C.P. to the extent where it is believed that vicariant speciation processes and events during global climatic changes have resulted in evolutionary driving forces that have had significant impacts on the biodiversity within the biogeographical boundaries of the W.C.P. (Vrba, 1985).

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Animals communicate via a variety of sensory channels and signals. Studies on acoustic and visual communication systems suggest that differences in the physical environment contribute to the variety of signalling behaviour, with species investing in those signals that are transmitted best under the local conditions. Whether or not environmental tuning also occurs in chemical communication systems has received much less attention. In the present study, we examined the effect of several aspects of the physical environment on the chemical communication system of lacertid lizards (family Lacertidae). The numbers of femoral pores are used as a proxy reflecting how much a particular species invests in and relies upon chemical signalling. Femoral pores are specialized epidermal structures that function as a secretion channel for the waxy substance produced by glands. In some lacertid species, the secretion carries infochemicals that play an important role in social communication. The number of femoral pores varies considerably among species. We have compiled data on femoral pore numbers for 162 species and tested for the effects of climate and substrate use. After correcting for body size and taking the phylogenetic relationships among the species into account, we found no effect of climate conditions or latitude on species pore numbers. Substrate use did affect pore numbers: shrub-climbing species tended to have fewer femoral pores than species inhabiting other substrates.

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Bicuar National Park (BNP) is a protected area in southwestern Angola where biodiversity has been poorly studied. BNP is located on the Angolan plateau on Kalahari sands, in a transition zone between the Angolan Miombo Woodland and the Zambezian Baikiaea Woodland ecoregions. Herpetological surveys were conducted in BNP and surrounding areas, through visual encounter surveys, trapping, and opportunistic collecting of specimens from 2015 to 2018. The regional herpetofauna is described here based on these surveys, literature records, and additional unpublished records. In total, 16 amphibian, 15 lizard, 18 snake, two testudine, and one crocodilian species were observed from the recent surveys, and in combination with historical records the species counts are 21, 36, 32, four, and one species for these herpetofauna groups, respectively. Important observations include the first record of Xenocalamus bicolor bicolor (Günther, 1868), the second records of Sclerophrys poweri (Hewitt, 1935) and of Amblyodipsas ventrimaculata (Roux, 1907), and the fourth record of Monopeltis infuscata (Broadley, 1997) for Angola. Additionally, the type locality of Hyperolius benguellensis (Bocage, 1893) is discussed. A part of the material could not be confidently identified to species level, reflecting the taxonomic uncertainty associated with the Angolan herpetofauna. Fossorial herpetofauna was well represented, reflecting adaptation to sandy soils, the dominant substrate in the area. The likely presence of endemic and poorly known species in BNP reinforces the importance of the park for the conservation of Angolan biodiversity. Further surveys are necessary for a more comprehensive understanding of the park’s fauna and biogeographic affinities, and to improve conservation planning.

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The Scaled Sandveld Lizard Nucras scalaris Laurent, 1964 is a poorly known lacertid endemic to north-eastern Angola and is only known from the type series collected more than half a century ago. The original description provided a comprehensive morphological description, but there was a lack of information regarding its evolutionary relationships and habitat associations. A recent discovery of N. scalaris from Cusseque, Bié Province, on the central Angolan plateau provided the opportunity to address some knowledge gaps of this species. A phylogenetic analysis confirmed its distinctiveness at the species level. Despite a limited dataset, the analysis suggests that N. scalaris is sister to N. broadleyi rather than N. lalandii, the latter having been assumed to be the sister species, because of morphological similarity between them. The new record of N. scalaris represents a range extension of more than 350 km to the southwest and extends the elevation range to 1570 m above sea level, compared to previous known localities at about 1 300 m above sea level (Alto Cuílo and Alto Chicapa, in Lunda Sul Province). The specimen also provides new information on live coloration, as well as the habitat association of grassy shrubland that is dominated by geoxylic suffrutices (the so-called ‘underground forests’) characteristic of the Angolan Miombo Woodlands. This new information raises the question whether poor survey data have led to an under-estimation of faunal diversity in this peculiar and overlooked vegetation type, and reinforces the need for further surveys which could highlight the importance of this habitat.

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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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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 striking new sandveld lizard of the Nucras tessellata group is described from the Lambert’s Bay Strandveld of the Western Cape Province, South Africa. It is sister to the clade N. livida + N. tessellata, and is phenetically most similar to N. tessellata, from which it differs in its more elongate body and possibly increased number of presacral vertebrae and patternless orange dorsal coloration. The form elegans, described as a species by Andrew Smith (1838), but treated as an infrasubspecific variant by Broadley (1972), also exhibits weak patterning, but is likely a regional color variant. Nucras aurantiaca sp. nov. is the ninth member of the genus found in southern Africa. Its discovery in the well-collected coastal Western Cape suggests that further herpetofaunal surveys are needed in this region, which is threatened by agricultural activity and tourism-related development.

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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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In the herpetological collection of ZFMK 528 scientific species group names are represented by type materi- al. Of these, 304 names are documented by primary type specimens (onomatophores) while for 224 further names sec- ondary type specimens (typoids) are available, ranging chronologically from 1801 to 2010. The list is a shortened pred- ecessor of a comprehensive type catalogue in progress. It lists name bearing types with their catalogue numbers includ- ing information on further type series members also in other institutions, while secondary types are listed only by pres- ence, both in ZFMK and other collections including holotype repositories. Geographic origin and currently valid names are also provided.

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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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A new endemic Sandveld Lizard, genus Nucras, is described from south-western Angola. Morphologically it resembles members of the Nucras tessellata group, but it is genetically separated and is sister to the larger tessellata + lalandii group. Although the genus is generally very conservative morphologically, the new species differs from other congeners in a combination of scalation, overall dorsal color pattern, and geographic separation. The new species is known from fewer than 12 specimens collected over a period spanning 120 years from arid south-western Angola. This brings the total number of species in the genus to 12 and adds another species to the growing list of endemic species of the Namib region of Angola. This new finding further reinforces the idea that this Kaokoveld Desert region is a key biodiversity area worthy of conservation and long-term protection.

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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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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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A phylogenetic-comparative approach was used to assess and refine existing secondary structure models for a frequently studied region of the mitochondrial encoded large subunit (16S) rRNA in two large lizard lineages within the Scincomorpha, namely the Scincidae and the Lacertidae. Potential pairings and mutual information were analyzed to identify site interactions present within each lineage and provide consensus secondary structures. Many of the interactions proposed by previous models were supported, but several refinements were possible. The consensus structures allowed a detailed analysis of rRNA sequence evolution. Phylogenetic trees were inferred from Bayesian analyses of all sites, and the topologies used for maximum likelihood estimation of sequence evolution parameters. Assigning gamma-distributed relative rate categories to all interacting sites that were homologous between lineages revealed substantial differences between helices. In both lineages, sites within helix G2 were mostly conserved, while those within helix E18 evolved rapidly. Clear evidence of substantial site-specific rate variation (covarion-like evolution) was also detected, although this was not strongly associated with specific helices. This study, in conjunction with comparable findings on different, higher-level taxa, supports the ubiquitous nature of site-specific rate variation in this gene and justifies the incorporation of covarion models in phylogenetic inference.

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A collection of reptiles and new locality records are reported from the littoral Southern Namib Desert, Northwestern Cape Province, Republic of South Africa. The new localities, by species, are: Chersina angulata, Swartlintjies River; Chondrodactylus angulifer, Swartlintjies River and Kleinsee; Agama atra, Papendorp, Swartlintjies River, and Kleinsee; Chamaeleo pumilus, MacDougall`s Bay; Mabuya occidentalis, Hondeklipbaal, Swartlintjies River, and Kleinsee; Acontias lineatus, Hondeklipbaal; Nucras tessellata, Kleinsee, and MacDougall`s Bay; Eremias capensis, Papendorp, Hondeklipbaal, and Kleinsee; Meroles knoxii, Elandsbaal; Meroles ctenodactyla, Papendorp, and Kleinsee; Psammophylax rhombeatus, Elandsbaal; Psammophis crucifer, Elandsbaal; and Naja nivea, Kreefbaal, and Kleinsee, 1978.

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A collection of reptiles and new locality records are reported from the littoral Southern Namib Desert, Northwestern Cape Province, Republic of South Africa. The new localities, by species, are: Chersina angulata, Swartlintjies River; Chondrodactylus angulifer, Swartlintjies River and Kleinsee; Agama atra, Papendorp, Swartlintjies River, and Kleinsee; Chamaeleo pumilus, MacDougall`s Bay; Mabuya occidentalis, Hondeklipbaal, Swartlintjies River, and Kleinsee; Acontias lineatus, Hondeklipbaal; Nucras tessellata, Kleinsee, and MacDougall`s Bay; Eremias capensis, Papendorp, Hondeklipbaal, and Kleinsee; Meroles knoxii, Elandsbaal; Meroles ctenodactyla, Papendorp, and Kleinsee; Psammophylax rhombeatus, Elandsbaal; Psammophis crucifer, Elandsbaal; and Naja nivea, Kreefbaal, and Kleinsee, 1978.

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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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The herpetological collections of the Museu do Dundo in Lunda Norte Province, northeast Angola, are among the most important in southern Africa and represent one of the largest collections of Angolan amphibians and reptiles in the world. The collection comprises more than 2,750 preserved specimens, including type specimens of taxa described by Raymond F. Laurent during the 1950s and 1960s,when he was affiliated with the Musee royal del’Afrique centrale (RMCA) in Tervuren, Belgium, and the Museum of Comparative Zoology (MCZ) at Harvard University, Cambridge, Massachusetts, where portions of these type series were also deposited. We provide details for all type specimens and summarize the history and taxonomy for each species represented in the type collection. The collections contain type specimens of 28 amphibian and reptile species, including seven snakes: Typhlops praeocularis lundensis, Dispholidus typus punctatus, Lycodonomorphus subtaeniatus, Lycophidion hellmichi, Gonionotophis brussauxi prigoginei, Prosymna ambıgua brevis, and Elapsoidea decosteri huilensis; 13 lizards: Rhoptropus boultoni montanus, Rhoptropus taeniostictus, Hemidactylus nzingae, Lygodactylus tchokwe, Cordylus vittifer machadoi, Chamaesaura anguina oligopholis, Gerrhosaurus bulsi, Nucras scalaris, Ichnotropis bivittata pallida, Mabuya bayonii huilensis, Mabuya ivensii septemlineata, Trachylepis raymondlaurenti, and Eumecia anchietae major; one amphisbaenian: Monopeltis vanderysti vilhenai; and seven frogs: Hyperolius machadoi,Hyperolius marmoratus alborufus, Hyperolius vilhenai, Ptychadena grandisonae, Ptychadena loveridgei, Ptychadena perplicata, and Ptychadena upembae machadoi. The typespecimens of the snake Xenocalamus bicolor machadoiwere not found in the collections. A brief history of the museum and remarks on the overall herpetological collections are also provided. We also note additional information about the related type material of these taxa at the MCZ.

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Namibe Province is the southernmost province of Angola and, as the result of sever- al expeditions from the nineteenth century to the present, it is one of the most her- petofaunally well-known areas of the country. The Province harbors a high diversi- ty of amphibians and reptiles, including roughly one-third of the reptile taxa report- ed for Angola as a whole. In this paper we present the results of a joint herpetologi- cal expedition to Namibe Province in 2013 by the California Academy of Sciences and the Instituto Nacionalda Biodiversidade e Áreas de Conservação, as well as a synoptic list of all the herpetological bibliographic records for the taxa known from the Province. A total of 37 herpetological taxa was collected, including at least three (then) undescribed species, two new country records, and new records for rarely cited taxa in Angola. These taxa belong to four amphibian genera and 15 reptile gen- era. Species accounts are provided for each of the species collected. We also highlight biogeographic patterns, conservation issues, and possible future paths for the explo- ration and knowledge of the herpetofauna of Namibe.

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Most lacertids are active foragers, but intrafamilial variation in foraging mode is greater than in most lizard families. We collected data on eight species of African lacertids to assess this variation. Both active and ambush foraging occurred within Pedioplanis and Meroles. Meroles ctenodactylus had a proportion of time moving and proportion of attacked prey detected while moving intermediate to those for actively foraging and ambushing Pedioplanis, but its number of movements per minute was exceptionally high. This species has a unique mixed foraging mode. Like active foragers, it seeks food by tongue-flicking while moving and spends a high percentage of the time moving. Like ambush foragers, it searches visually for prey during pauses between movements. Our findings confirm published data on four Kalahari lacertids. We discuss the history of foraging modes in advanced lacertids.

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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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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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The available material of the collection of reptiles and amphibians collected and described from 1831 by Andrew Smith, is re-examined to determine in how far it may be regarded as typical. A complete list of the new species described by Smith, together with notes and comments pertaining thereto, is given. Illustrated with a plate on the type specimen of Pelusios sinuatis.

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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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The Port Elizabeth Museum collection holds nearly 500 reptile specimens from Zambia and adjacent southeastern Democratic Republic of the Congo. These are reviewed, and biological and distribution data on 5 chelonians, 27 lizards and 38 snake species from Zambia are presented. These include information on 2 chelonians, 11 lizards and 19 snake species recorded from the poorly-known northern lVwinilunga District, Northwestern Province. Among the important findings are: the second largest specimen of and second Zambian locality for the dwarf terrapin, Pelusios nanus, with details on H`e first documented data on reproduction and sperm retention; the close proximity, without intergradation, of Lygodactylus heeneni and L. angularis suppOlting elevation of the former to specific status; a range extension of about 345km and the most northerly record (Chingola) for the gecko Lygodactylus chobiensis; a north-westerly range extension of more than 300km (to Chingola) for the gecko Hemidactylus mabouia (both these records may be translocations); the third and fourth reco]`ds for Zambia, and the most southern to date, for the gecko Pachydactylus tuberculosus; the first detailed biological information on the rare skink, Mabuya ivensii, which was first collected from Zanbia during these collections; asynchronous reproduction in Sakeji populations of both Mabuya maculilabris and M. wahlbergii; a southern range extension to Shimabala for the rare skink Eumecia anchietae; a range extension for the skink Lygosoma afrum to Sampfya town; the first record of lchnotropis capensis in the Copperbelt, and a north-westerly range extension of mon: than 300km to Chingola; the absence of asynchronous reproductive cycling between lchnotropis capensis and I bivittata in July at Sakeji; support for the specific status of Limnophis bangewoliCi,lS based on differences in colouration of the supralabials and subcaudals; new record sizes for both sexes of Dipsadoboa shrevei shrevei; a new record size for female Psammophis brevirostris leopardinus; and probable sympatry between Naja annulifera and its sister species N. anchietae at Livingstone.

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In recent years there has been an exponential increase in the amount of published DNA sequences, as it has become one of the most popular sources of data for reconstructing phylogenies. A number of studies have attempted to resolve the relationships of groups of lacertids using mitochondrial DNA sequence data, in particular Podarcis and Gallotia (e.g. THORPE et al., 1994; 1996; GONZALEZ et al., 1996; FU et al., 1997; HARRIS, 1997; HARRIS et al., 1998a; 1999; CASTILLA et al., 1999a,b). Reassessment of these data suggest some alternative phylogenies to those previously published, and also highlight possible problems. Two studies have attempted to unravel the phylogeny of the whole family using mitochondrial DNA sequences (FU, 1998; HARRIS et al., 1998b). By combining these essentially congruent data sets, and reanalysing levels of support for the phylogenies produced, a more complete estimate of relationships across the family is produced. This is then compared to alternative sources of evidence, primarily morphological (ARNOLD, 1989), biochemical (MAYER & BENYR, 1994) and karyological (OLMO et al., 1993). Reasons for discrepencies are discussed, as are the relative advantages and disadvantages of the different sources of phylogenetic inference.

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DNA sequences from parts of the 12S, 16S and cytochrome b mitochondrial genes, which totalled 1049 aligned base pairs, were used to estimate the relationships of 49 species of Lacertidae, including representatives of 19 out of the 23 recognized genera and 23 species of the paraphyletic genus Lacerta. These data were used, together with morphological information, to estimate the relationships within the family. Molecular evidence corroborates the monophyletic status of many genera and species groups originally based on morphology. It indicates that Psammodromus forms a clade with Gallotia, which is the sister taxon of all other lacertids. These comprise three units: the primarily Afrotropical armatured group; the largely Oriental Takydromus; and the west Palaearctic Lacerta and its derivatives, Podarcis and Algyroides. Morphology also supports the first three assemblages, but suggests that they are derived from a paraphyletic Lacerta. Within Lacerta and its allies, DNA sequence analysis corroborates the affinity of some members of each of the subgenera Lacerta s. str. and Timon, and of the L. saxicola group. It also supports the relationship of L. monticola, L. bonnali and L. horvathi, and suggests that the L. parva–L. fraasi clade and L. brandti are not related to Psammodromus–Gallotia, as morphology indicates, but instead are associated respectively with the L. danfordi and L. saxicola groups. DNA sequence data provide additional evidence that the eastern Arabian `Lacerta` jayakari and `L.` cyanura are members of the armatured clade and also sister species. Our analysis supports an origin for present lacertids in west Eurasia. The armatured clade invaded Africa, probably in the mid-Miocene, spreading widely and evolving increasingly xeric-adapted forms, one lineage of which later moved back into the Palaearctic. `Lacerta` jayakari and `L.` cyanura are assigned to Omanosaura, Lutz and Mayer 1986. The name Gallotiinae Cano, Baez, Lopez-Jurado and Ortega, 1984 is available for the Gallotia–Psammodromus clade, Eremiainae Shcherbak 1975 for the armatured clade and Lacertinae for Lacerta, Podarcis and Algyroides. Two new subgenera of Lacerta are proposed here: Caucasilacerta for L. saxicola and its allies, and Parvilacerta for L. parva and L. fraasi.

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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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While global variation in taxonomic diversity is strongly linked to latitude, the extent to which morphological disparity follows geographical gradients is less well known. We estimated patterns of lineage diversification, morphological disparity and rates of phenotypic evolution in the Old World lizard family Lacertidae, which displays a nearly inverse latitudinal diversity gradient with decreasing species richness towards the tropics. We found that lacertids exhibit relatively constant rates of lineage accumulation over time, although the majority of morphological variation appears to have originated during recent divergence events, resulting in increased partitioning of disparity within subclades. Among subclades, tropical arboreal taxa exhibited the fastest rates of shape change while temperate European taxa were the slowest, resulting in an inverse relationship between latitudinal diversity and rates of phenotypic evolution. This pattern demonstrates a compelling counterexample to the ecological opportunity theory of diversification, suggesting an uncoupling of the processes generating species diversity and morphological differentiation across spatial scales.

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Closely related lacertid lizards (Eremias, Nucras) in the Kalahari desert differ in patterns of foraging behaviour. Some species are relatively sedentary (‘sit-and-wait’) whereas others are more active (‘widely-foraging’) predators. We determined whether whole-animal locomotor capacities (cruising endurance on a treadmill, initial speed and maximum burst speed in a racetrack, and sprint endurance in a torus-shaped track) correlated with interspecific differences in foraging behaviour. Two of three widely-foraging species had greater cruising endurance, graater sprint endurance, but lower burst speed than did a sit-and-wait species. However, the two species that sprinted quickly also had limited endurance, and vice versa. Pre-feeding negatively influenced endurance but not sprint capacity. Theoretical models of foraging behaviour should recognize that ectotherms have limited endurance, that there can be a trade-off between speed and endurance, and that pre-feeding can reduce some aspects of locomotor capacity.

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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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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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Few reports on fire-induced reptile mortality in African savanna have been published. To quantify fire-induced reptile mortality surveys were conducted during a scheduled austral spring management fire in savanna habitat at Lapalala Wilderness, a private game reserve in Limpopo Province, South Africa to determine the density of fatalities and identify possible fire associated mechanisms of mortality. Several transects were conducted at sites within a single block burn. Surveys produced 15 fatalities from eight squamate species, most of which showed varying degrees of denuded respiratory cilia, suggestive of heated air inhalation, potentially proving fatal for some collected specimens.

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the Lacertidae is one of the most diverse and widespread lizard families throughout Eurasia and Africa. Several studies so far have attempted to unravel the phylogeny of Lacertidae using morphological and mole- cular data. However, the intra-family relationships remain unclear. in an effort to explore the phylogenetic relationships within the family Lacertidae, a concatenated dataset of 5727 bp from six genes (two nuclear and four mitochondrial) and 40 genera was assembled based on GenBank database. Phylogenetic inference analy- ses were conducted using Maximum Parsimony (MP), Bayesian inference (Bi) and Maximum Likelihood (ML), revealing that even a combined dataset of both mitochondrial and nuclear genes is not able to resolve the phylogenetic relationships of the Lacertidae family under the tribe level.

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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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The Soutpansberg situated in north-eastern South Africa was investigated with respect to its reptile species diversity, geographic range of the species and habitat utilisation. Typical inselberg characteristics are discussed in the context of the herpetofauna and compared with the Blouberg, an isolated mountain range to the west of the Soutpansberg. Possible biogeographic links between the species assemblage of the Soutpansberg and adjacent areas are discussed in the context of present geological and climatic conditions within the area. The Soutpansberg reptile community clearly shows effects of isolation. The mistbelt and the grassland on the summits, which both withstood climatic oscillations in the past, harbour the majority of species and most of the endemic taxa in particular. Hence, these areas are of significant ecological value for the reptile community. Rocky habitats and the cooler and moister climate on the mountain provide exceptional conditions within this area. Most of the Soutpansberg endemics exhibit a rupicolous lifestyle and a large number of species are adapted to mesic conditions. A high proportion of Afromontane species was detected. Furthermore, eastern coastal and Lowveld elements exert an influence on the species composition whereas the Kalahari elements are of lesser importance. Tropical forest species are completely absent. The Soutpansberg harbours more endemics (nine taxa) compared to the Blouberg (three taxa) due to its larger size and the resultant decreased risk of extinction.

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The dangers of helminth infestations for lizards, particularly infestations with nematodes und cestodes, are reported. Infection routes, diagnoses, und treatments are described.

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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 diversity of lacertid lizards in Africa is highest in the southern African subcontinent, where over two-thirds of the species are endemic. With eleven currently recognized species, Pedioplanis is the most diverse among the southern African genera. In this study we use 2200 nucleotide positions derived from two mitochondrial markers (ND2 and 16S rRNA) and one nuclear gene (RAG-1) to (i) assess the phylogeny of Pedioplanis and (ii) estimate divergence time among lineages using the relaxed molecular clock method. Individual analyses of each gene separately supported different nodes in the phylogeny and the combined analysis yielded more well supported relationships. We present the first, well-resolved gene tree for the genus Pedioplanis and this is largely congruent with a phylogeny derived from morphology. Contrary to previous suggestions Heliobolus/Nucras are sister to Pedioplanis. The genus Pedioplanis is monophyletic, with P. burchelli/P. laticeps forming a clade that is sister to all the remaining congeners. Two distinct geographic lineages can be identified within the widespread P. namaquensis; one occurs in Namibia, while the other occurs in South Africa. The P. undata species complex is monophyletic, but one of its constituent species, P. inornata, is paraphyletic. Relationships among the subspecies of P. lineoocellata are much more complex than previously documented. An isolated population previously assigned to P. l. pulchella is paraphyletic and sister to the three named subspecies. The phylogeny identifies two biogeographical clades that probably diverged during the mid-Miocene, after the development of the Benguella Current. This probably led to habitat changes associated with climate and, in conjunction with physical barriers (Great Escarpment), contributed towards speciation within the genus Pedioplanis.

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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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Habitat transfonnation is the primary anthropogenic threat to global biodiversity. Fragmentation of reptile populations following habitat transfonnation within a landscape can lead to the extirpation of species. We investigated the effects of land-use on the species richness and abundance of reptile assemblages in three habitat types (two natural and one modified) in the grasslands of Gauteng, South Africa. Using trap arrays, we surveyed reptiles in primary grassland with little or no rock cover, primary grassland with large quartzite outcrops and scattered rocks, and secondary grasslands that were historically ploughed and cropped. We measured vegetation height and vegetation cover at these same localities. We caught significantly fewer reptile species in the historically cultivated sites than in either of the two natural habitat types. Differences in the reptile assemblage of each habitat type were not explained by either the spatial location or the vegetation structure of our trap sites but were well explained by the sites` habitat type. Estimates of total species richness indicated that we were able to adequately sample the reptile assemblages in the three habitat types, further supporting our observation of reduced species richness in the secondary grasslands. We infer that habitat transfonnation associated with cultivation e.g., rock removal, has had a detectable, negative impact on the species richness and composition of the local reptile assemblages. We recommend that land-use planning in Gauteng emphasise the need for areas of inter-connected, untransfonned habitat in order to mitigate the negative impacts of habitat transfonnation on the local reptile diversity.

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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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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.

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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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Point distribution data were used to evaluate the biogeographical influence of the arid Tankwa Karoo Basin on the distribution of reptiles in the south-western districts of South Africa. Under-representation of the Tankwa Karoo in the dataset required an additional field survey of this region. Prior to the survey, available records from the Tankwa Karoo Basin represented only 13 reptile species. A total of 36 species (24 lizards, nine snakes, three chelonians) was recorded during our survey of this area. Turnover across the Basin is high, species richness is lower than in surrounding mountainous areas and there are no species endemic to the area. The Tankwa Karoo Basin acts as a dispersal barrier for many reptile species occurring in the surrounding more mesic areas. At the same time, the ranges of a number of typical northern, arid-adapted species extend southward along the Tankwa plains. A number of species range extensions in the region are reported.

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Point distribution data were used to evaluate the biogeographical influence of the arid Tankwa Karoo Basin on the distribution of reptiles in the south-western districts of South Africa. Under-representation of the Tankwa Karoo in the dataset required an additional field survey of this region. Prior to the survey, available records from the Tankwa Karoo Basin represented only 13 reptile species. A total of 36 species (24 lizards, nine snakes, three chelonians) was recorded during our survey of this area. Turnover across the Basin is high, species richness is lower than in surrounding mountainous areas and there are no species endemic to the area. The Tankwa Karoo Basin acts as a dispersal barrier for many reptile species occurring in the surrounding more mesic areas. At the same time, the ranges of a number of typical northern, arid-adapted species extend southward along the Tankwa plains. A number of species range extensions in the region are reported.

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During a journey to Tanzania in September/October 1997 Nucras boulengeri was observed in the Uluguru Mountains. Its habitat as well as its appearence, distribution and keeping in captivity are described. For the first time the courtship behaviour is documented, the male uses a neck bite during copulation. Until now no pregnancy occured. The ovary of a dead female from the same locality contained four eggs with an average size of 10,5 x 5,5 mm.

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Many animals display complex colour patterns that comprise several adjacent, often contrasting colour patches. Combining patches of complementary colours increases the overall conspicuousness of the complex pattern, enhancing signal detection. Therefore, selection for conspicuousness may act not only on the design of single colour patches, but also on their combination. Contrasting long- and short-wavelength colour patches are located on the ventral and lateral surfaces of many lacertid lizards. As the combination of long- and short-wavelength-based colours generates local chromatic contrast, we hypothesized that selection may favour the co-occurrence of lateral and ventral contrasting patches, resulting in complex colour patterns that maximize the overall conspicuousness of the signal. To test this hypothesis we performed a comparative phylogenetic study using a categorical colour classification based on spectral data and descriptive information on lacertid coloration collected from the literature. Our results demonstrate that conspicuous ventral (long wavelength-based) and lateral (short wavelength-based) colour patches co-occur throughout the lacertid phylogeny more often than expected by chance, especially in the subfamily Lacertini. These results suggest that selection promotes the evolution of the complex pattern rather than the acquisition of a single conspicuous colour patch, possibly due to the increased conspicuousness caused by the combination of colours with contrasting spectral properties.

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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 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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Four lacertid lizards, Pedioplanis laticeps, P. lineo-ocellata, Meroles knoxii and Nucras tessellata, occur sympatrically on the arid plains of the Tankwa Karoo Basin in South Africa. The aim of this study was to evaluate the significance of foraging strategy in resource partitioning among the four species, allowing them to co-occur in a structurally simple system with a limited number of potential niches. Previous workers already identified P. lineo-ocellata and M. knoxii as sit-and-wait foragers and N. tessellata as an active forager. We recorded data on three foraging variables: movements per minute, proportion of time spent moving, and proportion of attacks on prey whilst moving, for juveniles and adults of P. laticeps. By comparing the foraging data obtained for P. laticeps to those for other lacertid species, we were able to demonstrate that adult P. laticeps are ambush foragers. We also noted a significant ontogenetic shift in foraging behaviour in P. laticeps, and, due to a significantly higher frequency of short brief movements, we classified juveniles as mixed foragers. The sharing of an ambush foraging strategy by at least three of the four lacertid species co-occurring on the Tankwa plains, suggests considerable overlap along the trophic dimension of ecological space. This overlap presumably promotes occupation of separate microhabitats by the three ambush foragers in the Tankwa Karoo Basin.

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Four lacertid lizards, Pedioplanis laticeps, P. lineo-ocellata, Meroles knoxii and Nucras tessellata, occur sympatrically on the arid plains of the Tankwa Karoo Basin in South Africa. The aim of this study was to determine whether the four species are spatially separated in terms of the microhabitat each species occupies, allowing them to occur in sympatry in this structurally simple system with a limited number of potential niches. The habitat preferences of the four species were investigated on the farm Gansfontein in the southwestern parts of the Tankwa Karoo Basin. The area was surveyed by walking transects through different habitat types and recording all active lizards. For each lizard observed, the species was identified and a photograph was taken of its microhabitat. At the end of the sampling period the microhabitats in which lizards were found were sorted into distinct types on the basis of substrate composition. During the survey, only one individual of N. tessellata was recorded, but sample sizes for the other three species were sufficiently large to provide a clear perspective of habitat segregation among the three species. The results showed that the three species are spatially separated at the study site, with P. lineo-ocellata being restricted to rocky areas, P. laticeps preferring gravel substrates and M. knoxii frequenting sandy areas. Although only anecdotal information is available, all indications are that the observed spatial separation of the three species is mainly the result of historical adaptation to the different substrate types.

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While the stability of sex chromosomes is widely accepted in viviparous mammals and birds, ectothermic vertebrates are still largely viewed as having frequent turnovers in sex determining systems. Frequent changes in sex determining systems in ectotherms could be problematic for field ecological studies as well as for breeding programs, as molecular sexing across a phylogenetically widespread spectrum of ectothermic vertebrates would not be possible. However, we recently documented that sex determining systems in three important reptile lineages (caenophidian snakes, iguanas, and lacertid lizards) are in fact highly conserved. 2.We applied a new molecular procedure to identify sex within each of these three lineages (encompassing altogether around 4,000 species, i.e. nearly 50% of the recent species of reptiles). This technique uses quantitative PCR (qPCR) to compare copy numbers of genes specific for their respective Z (in caenophidian snakes and lacertids) and X (in iguanas) chromosomes between male and female genomes. The DNA samples required can be collected relatively non-invasively. Unlike molecular sexing based on repetitive elements, this technique can be easily applied to previously unstudied species of these lineages, as the number of copies of protein coding genes linked to the differentiated sex chromosomes is evolutionary highly conserved in each. 3.We suggest that qPCR-based molecular sexing using the comparison of gene copy number is a practical choice for non-model species of caenophidian snakes, iguanas and lacertids. Morever, it should also soon be available for other reptile lineages with differentiated sex chromosomes.

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

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The staggering phenotypic variation among organisms and the striking fit between an organism`s morphology and its environment have fascinated naturalists for centuries. Darwin`s publication of `On the origin of species` was the first to offer an explanation for the apparently perfect form-function relationship. During the past century overly enthousiastic evolutionary biologists interpreted any direct link between an organism`s morphology and ecology as evidence for the theory of evolution by natural selection. However, for morphological variation to be considered adaptive it is necessary to explicitly test how this variation translates into the variation in ecologically relevant performance traits, which in turn translates into ecological (and fitness) variation. Nowadays, performance- based ecomorphological approaches are typically used to test the adaptive nature of phenotypic variation in order to provide a better understanding of the selective pressures operating on organisms. Using an ecomorphological approach, lacertid lizards have been used extensively to test whether and how they are adapted to their environment. The majority of these studies have mainly included European species, leaving African species underrepresented. This is suprising from an evolutionary viewpoint. Compared to European lacertids, African lacertid lizard clades are older and more speciose. Also, lacertid lizard communities on the African continent are more complex than the ones in Europe (i.e. comprising 7-8 species versus 2-3 species). In this talk, we will focus on the phenotypic divergence among African clades and the link with the variation in performance and ecology, and explicitly compare these results to results on European lacertids.

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Locomotion is important to animals because it has direct implications for fitness through its role in predator escape, prey capture, and territory defence. Despite significant advances in our understanding of animal locomotion, studies exploring how substrate properties affect locomotor performance remain scant. In the present study, we explore how variation in substrate (sand, slate, cork) affects locomotor performance in lacertid lizards that differ in morphology. Moreover, we explore whether substrate effects are the same for different types of locomotor performance (speed, acceleration, and stamina). Our results show that the substrate affected most types of locomotor performance studied but not always in the same way. Although substrate effects were species-dependent for the maximal speed over 50 cm and the distance run to exhaustion, this was not the case for acceleration capacity. These results suggest that substrate texture differentially affects burst performance vs. longer duration measures of locomotor performance. Finally, straightforward relationships between habitat use and the substrate on which performance was maximized were not observed. This suggests that the evolution of locomotor capacity is complex and that animals may show compromise phenotypes allowing them to deal with a variety of substrates in their natural environment.

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Shape variation in the vestibular system is often linked to microhabitat structure and locomotor performance. Highly circular and orthogonal semicircular canal pairs are linked to higher motion sensitivity. Here, we use 3D geometric morphometrics to investigate shape variation in the vestibular system within lacertid lizards and its relationship to balance control. We found that lacertids living in complex microhabitats possess narrow but longer vestibular systems, an S-shaped anterior canal, a straightened lateral canal and a short common crus. However, lacertids specialized for simple microhabitats (open areas) possess wider but shorter vestibular systems, more circular anterior and lateral canals, and a longer common crus. Contrary to our expectations, species living in simple microhabitats possess more anatomical adaptations that enhance the sensitivity of their vestibular system. This suggests that species inhabiting open areas may benefit from increased sensitivity given that they are potentially more visibile to predators and have lower shelter availability. Finally, the wider shape of the vestibular system of the open area species may be linked to a wider and potentially flattened skull, which may be related to sand-diving or prey hardness.

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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.