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Estimates of phylogeny may allow historical events to be reconstructed even without a fossil record. The reliability of such interpretations depends not only on the robustness of the phylogeny but also on its topology. Changes in individual features can be traced and general histories of groups developed and compared with each other. Results are ofter surprising, for Instance the sophisticated tail shedding mechanism of lizards turns out to be a primitive feature that has been lost many times. Similarly, ecological analogues may have developed their common characaters in quite different orders. Phylogenies also provide a way of recognizing constraints and the effects of history on present ecological and behavioural patterns. When using anatomical characters the quality of the apparent phylogenies produced may be related to ecological history: expansion of a group along an ecological continuum into increasingly demanding niches ina small geographical area tends to produce a robust phylogeny (for instance in Meroles), while this is often not so for widely distributed groups that occupy a more modest range of niches (such as Pedioplanis and Podarcis). Non-morphological data may not show this tendency, but can have their own problems. Lacertids can be referred to clade with many successive branches in Africa and the Saharo-Eurasian arid zones and a less resolved probably paraphyletic complex of more primitive forms in the Mediterranean and wider Palaearctic areas. The African-Eurasian clade shows a general trend towards ground-dwelling and increasingly arid habitats but is ecologically variied. These animals are important to the study of Mediterranean forms because they provide eco-morphological parallels to them (for instance to Algyroides, Psammodromus and the archaeolacertas) and help form a basis for testing hypotheses about function. Although it is possible to recognise a number of distinct clades among the Mediterranean and Eurasian forms, relationships within and between these are often much less well substantiated. If results are available in time, current work on mitochondrial DNA sequencing will be discussed.

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

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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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Data derived from the morphology of the seven species of South African sand lizards, Meroles (Reptilia, Lacertidae), and their outgroups produce a robust estimate of phylogeny when a maximum parsimony approach is applied. The estimate is fully resolved with little character conflict and internal branches are relatively long. This analysis indicates that Meroles is a true clade that includes the aberrant lacertid long separated as Aporosaura anchietae. The tree is pectinate, its successive external branches representing species with increasing adaptation to desert conditions, especially aeolian sand habitats. This pattern, and the robustness of the tree, support a model of invasion of severe habitats in which successive rounds of speciation, displacement, and adaptation result in spread into extreme ecological situations. To test the robust morphological phylogeny and, indirectly, the model as well, DNA from mitochondrial 12S and 16S ribosomal genes was sequenced and analyzed by both maximum parsimony and maximum likelihood approaches. Trees produced were largely congruent with that derived from morphology, although different from ones resulting from protein electrophoresis. However, in contrast to the internal branches of the morphological tree, those of the DNA maximum likelihood tree are quite short. The DNA data provide some corroboration for the relationships within Meroles based on morphology and consequently for the model as well. The disparity in internal branch lengths between the maximum parsimony morphological and maximum likelihood DNA trees may well indicate that the multiple adaptations to desert conditions arising on the main lineage of Meroles evolved quite rapidly. In this study DNA thus not only corroborates the phylogeny but also provides evidence about another aspect of evolutionary history.

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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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Reptiles are supposed to be relatively invulnerable to the ongoing rapid anthropogenic climate change as they are able to actively regulate their body temperature (Tb) through behaviour, tolerate high Tb and resist water loss. However, recent studies have shown that lizards and snakes seem to be more at risk than previously expected. In Mexico, increased local extinction probability in lizards correlated with the magnitude of warming during the reproductive period, questioning the assumption of climate invulnerability. We tested the hypothesis that different lizard species of the family Lacertidae are vulnerable to rises in maximum temperatures in Namibia, especially in the Namib and the Kalahari. We predicted that inhabiting different habitats with different microhabitat temperatures and different preferred Tb within different distribution ranges would result in differences in local extinction probability. As opposed to other studies our model integrates past and present distributions verified by museum collections and ground-truthed, a quantifiable physiological parameter (preferred body temperature Tpref) and available operative temperatures in correlation to air temperatures. Data was collected for 17 species (Meroles anchietae, M. cuneirostris, M. suborbitalis, M. ctenodactylus, M. reticulatus, M. micropholidotus, M. knoxii, Pedioplanis namaquensis, P. laticeps, P. lineoocellata, P. breviceps, P. rubens, P. undata, P. inornata, P. gaerdesi, P. husabensis and Heliobolus lugubris). Our first results seem to indicate that populations of at least one of the tested species were extirpated (both predicted by the model and verified) in the hottest area of its distribution range due to increased maximum temperatures during the reproductive season since the mid-1970s. Furthermore, different extents in future extinction risk are predicted under consideration of the currently accepted climate change scenarios. It seems that Namibian Lacertidae under current conditions already live at their thermal maximum.

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Aim To map and assess the richness patterns of reptiles (and included groups: amphisbaenians, crocodiles, lizards, snakes and turtles) in Africa, quantify the overlap in species richness of reptiles (and included groups) with the other terrestrial vertebrate classes, investigate the environmental correlates underlying these patterns, and evaluate the role of range size on richness patterns. Location Africa. Methods We assembled a data set of distributions of all African reptile species. We tested the spatial congruence of reptile richness with that of amphibians, birds and mammals. We further tested the relative importance of temperature, precipitation, elevation range and net primary productivity for species richness over two spatial scales (ecoregions and 1° grids). We arranged reptile and vertebrate groups into range-size quartiles in order to evaluate the role of range size in producing richness patterns. Results Reptile, amphibian, bird and mammal richness are largely congruent (r = 0.79–0.86) and respond similarly to environmental variables (mainly productivity and precipitation). Ecoregion size accounts for more variation in the richness of reptiles than in that of other groups. Lizard distributions are distinct with several areas of high species richness where other vertebrate groups (including snakes) are species-poor, especially in arid ecoregions. Habitat heterogeneity is the best predictor of narrow-ranging species, but remains relatively important in explaining lizard richness even for species with large range sizes. Main conclusions Reptile richness varies with similar environmental variables as the other vertebrates in Africa, reflecting the disproportionate influence of snakes on reptile richness, a result of their large ranges. Richness gradients of narrow-ranged vertebrates differ from those of widespread taxa, which may demonstrate different centres of endemism for reptile subclades in Africa. Lizard richness varies mostly with habitat heterogeneity independent of range size, which suggests that the difference in response of lizards is due to their ecological characteristics. These results, over two spatial scales and multiple range-size quartiles, allow us to reliably interpret the influence of environmental variables on patterns of reptile richness and congruency.

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

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Die Wüstenrenner-Eidechsen Namibias werden derzeit in folgende vier Gattungen eingeteilt: Pedioplanis, Meroles, Aporosaura und Heliobolus. Während zweier Reisen konnten sie im Freiland studiert werden. Im Terrarium wurden sieben Arten gehalten, von denen vier Arten nachgezüchtet werden konnten. Neben Pedioplanis rubens, P. lineoocellata pulchella und P. namaquensis erweist sich vor allem Meroles cuneirostris als ein sehr gut zu haltendes, interessantes Terrarientier.

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Lizards are a diverse clade in which one radiation consists entirely of sit-and-wait foragers and another consists of wide foragers. Lizards utilizing these two foraging modes are known to differ in diet, but little is known about how feeding morphology relates to diet and/or foraging mode. This study tested the hypothesis that skull morphology and biting performance are related to diet preference, and consequently, coevolve with foraging mode. Four species of lacertid lizard were studied because they vary in foraging mode, their phylogenetic relationships are known and they are well studied ecologically. Using an ‘ecomorphological’ approach, skull morphology and biting performance were quantified and mapped on to the phylogeny for the species. The results indicate that sit-and-wait species have shorter, wider skulls than the wide foraging species, and that all are significantly different in overall head shape. The sit-and-wait species had similar values for biting performance; however, clear phylogenetic patterns of covariation were not present between sit-and-wait and wide foraging species for either biting performance or skull morphology. Thus, skull morphology and performance have little influence on diet and foraging mode in these species. Instead it is likely that other factors such as seasonal prey availability and/or life history strategy shape foraging mode decisions.

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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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The present paper of N. N. SZCZERBAK was originally published in Russian as `Katalog afrikanskih Jascurok` by the Academy of Sciences, Institute of Zoology, Museum of Zoology, USSR, Kiev (83 pp., 30 maps) in 1975. Lists of synonyms, bibliography, maps and table of contents - all being parts of the original paper - have not been included in this translation which was carried out with the consent of the author by R. GÜNTHER (Berlin) and H. GRILLITSCH (Vienna). The English summary was taken over as provided in the original version. As a SHORT NOTE in this issue of HERPETOZOA subsequent to the translation comments and updated addenda by W. MAYER are provided indicated by [aa* bb* etc.] in the text.