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We measured the effects of deltamethrin, a pyrethroid insecticide, on individuals of two lizard species,Meroles suborbitalis and Pedioplanis namaquensis, in enclosures under controlled conditions, and under field conditions. We found significant effects on lizard mortality rates in the enclosure experiments, with most lizards dying within two months of treatment. Our field-based investigation, conducted over a five-month period, revealed significant reductions in abundance of M. suborbitalis (reduced by 52%) and P. namaquensis, (reduced by 72%) one and four weeks after spraying with deltamethrin. At 18 weeks after spraying there was no longer a significant difference in abundance measures between treatment and control plots, due to the invasion of the plots by juveniles.

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The persistence of populations is based on the optimization of reproductive processes as a means of compensating for the loss of individuals through mortality. One way of reaching this equilibrium is the coadaptation of reproductive traits defining different strategies. I explored these tactics in lacertid lizards by analysing the covariation between, on the one hand, clutch size and frequency, and on the other, egg mass, using independent contrast data from 42 species. In addition, I examined the influence of female and newborn size on these variables. All the traits investigated, with the exception of clutch frequency, are influenced by female body size, reflecting physical constraints on reproductive output. The negative trade-off between clutch size and newborn size on one hand and egg mass on the other is congruent with the partitioning of energetic resources to produce a few large or numerous small descendents. Clutch frequency is unrelated to the other female reproductive traits.

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The structure of copulatory organs is used very widely in systematics, both for differentiating species and for working out relationships. Differences between taxa may arise from a variety of sources, including non-homology, differences in other parts of the animal, direct selection on copulatory organs, development of physical isolating mechanisms and pleiotropic events. Physical isolating mechanisms seem likely to account for the abrupt differences, involving size, asymmetry and simplifications, that are useful in distinguishing very similar lacertid species. Although these differences usually seem to arise at the end of a speciation event they can simultaneously be the initiating mechanism in a second one. Copulatory organs appear to have high inherent stability, probably resulting from frequent location in strongly homoeostatic environments, single function, insensitivity to niche shift and inertia due to the need to conform to the genitalia of the opposite sex. This stability may be overridden at times by direct selection on the organs themselves or pleiotropic events. Such changes tend to be retained because efficiency in copulation depends not on any absolute genital architecture but on close conformity of the organs. It is the combination of relative stability and tangible input of varied change, which tends to be retained, that so often makes these structures good indicators of relationship.

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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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Phylogenies based on morphology vary considerably in their quality: some are robust and explicit with little conflict in the data set, whereas others are far more tenuous, with much conflict and many possible alternatives. The main primary reasons for untrue or inexplicit morphological phylogenies are: not enough characters developed between branching points, uncertain character polarity, poorly differentiated character states, homoplasy caused by parallelism or reversal, and extinction, which may remove species entirely from consideration and can make originally conflicting data sets misleadingly compatible, increasing congruence at the expense of truth. Extinction differs from other confounding factors in not being apparent either in the data set or in subsequent analysis. One possibility is that variation in the quality of morphological phylogenies has resulted from exposure to different ecological situations. To investigate this, it is necessary to compare the histories of the clades concerned. In the case of explicit morphological phylogenies, ecological and behavioural data can be integrated with them and it may then be possible to decide whether morphological characters are likely to have been elicited by the environments through which the clade has passed. The credibility of such results depends not only on the phylogeny being robust but also on its detailed topology: a pectinate phylogeny will often allow more certain and more explicit statements to be made about historical events. In the case of poor phylogenies, it is not possible to produce detailed histories, but they can be compared with robust phylogenies in the range of ecological situations occupied, and whether they occupy novel situations in comparison with their outgroups. LeQuesne testing can give information about niche homoplasy, and it may also be possible to see if morphological features are functionally associated with ecological parameters, even if the direction of change is unknown. Examination of the robust and explicit phylogeny of the semaphore geckoes (Pristurus) suggests that its quality does stem from a variety of environmental factors. The group has progressed along an ecological continuum, passing through a series of increasingly severe niches that appear to have elicited many morphological changes. The fact that niches are progressively filled reduces the likelihood of species reinvading a previous one with related character reversal. Because the niches of advanced Pristurus are virtually unique within the Gekkonidae the morphological changes produced are also very rare and therefore easy to polarize. Ecological changes on the main stem of the phylogeny are abrupt and associated character states consequently well differentiated. The small geographical distribution of the group reduces the chance of different forms entering the same niche and developing morphological parallelisms. Many species are represented because there are many refuge areas within the geographical distribution of Pristurus and also because the fact that niches are well differentiated reduces the chance of extinction by species competition. Examination of ten other lizard clades, mainly in the Lacertidae, shows that the historical features noted in Pristurus also occur in other groups with robust and explicit morphological phylogenies, such as Meroles and Gastropholis. On the other hand, they are often absent in assemblages where phylogenetic hypotheses based on anatomy are poorly supported or equivocal, for example Podarcis and Pedioplanis. The amount of alteration of genital features is not as closely associated with environmental factors as in many other morphological characters, possibly because ecological shifts do not affect them so directly and because they have their own special causes of change. This partial independence from the environmental factors that appear to control many characters means that genital features may enable some phylogeny reconstruction to be done, even when other systems are unhelpful. There is no evidence among the studied clades that groups with poor morphological phylogenies have inherent general constraints on the development and maintenance of new structural features. It seems that the quality of morphological phylogenies may give some indication of the kinds of history groups have had. Clearly, if the variety of ways in which evolution proceeds is to be understood, groups with both good and bad morphological phylogenies must be investigated.

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Phylogenetic analyses, using parsimony and compatibility methods, were carried out on the South African lacertid lizards assigned in recent times to Aporosaura, Meroles and Pedioplanis. These were based on 80 primary and 102 binary morphological characters which were drawn from osteology, external features, muscles, kidneys and reproductive systems. Contrary to some previous interpretations, there are two well-defined clades: Meroles plus Aporosaura, and Pedioplanis; these form successive branches on the main stem of the phylogeny of advanced lacertids. The clades show considerable parallel development of derived features, presumably because they had very similar initial genetic potential. Relationships within the two groups are shown on p. 800 and p. 802. As Aporosaura anchietae is sister taxon to a clade consisting of three of the seven species of Meroles, it has been transferred to that genus. Relationships in Meroles-Aporosaura are very well substantiated, in contrast to the situation in Pedioplanis. This difference appears to be related to the different kinds of evolutionary history that the two groups have had. The Meroles-Aporosaura clade has spread progressively into increasingly stringent and singular aeolian sand environments which have elicited the production of many, often unique, derived character states related to the functional problems of survival in such situations. As these states are rarely duplicated in outgroups, the characters concerned are easily polarized. This, together with their abundance, means that a robust basis for phylogenetic inference is available. In contrast, Pedioplanis exhibits relatively limited ecological radiation of a kind that also occurs in related groups, and the functionally related derived states elicited are fewer and less distinctive. In fact, production of a phylogeny for Pedioplanis is very dependent on genital characters which seem to be substantially independent of the main ecological changes that have occurred in the genus. The premaxilla is embraced dorsally by the anterior processes of the maxillae in most lacertids, but the processes are less extensive in two sister species of Pedioplanis, P. burchelli and P. laticeps. This modified condition also occurs in the genera Eremias, Acanthodactylus, Mesalina and Ophisops, which together constitute a clade that forms the sister group of Pedioplanis. The modification provides extra evidence for the holophyly of the clade, even though presence in some Pedioplanis shows it to be homoplasious.

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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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Ecological analogues provide an opportunity to assess the regularity of the evolutionary process and some of the factors that control this. By using cladistic methods of phylogeny reconstruction, it is possible to see if two or more stocks have responded in the same way to similar environments, or whether factors such as accident, contingency and previous history have restricted such orderliness. A method is described for comparing the sequences in which ecological analogues assemble their common traits, including ways of handling incomplete data and of testing the statistical significance of the results. The method is applied to situations that mainly involve lizard groups independently associated with aeolian sand habitats. A case where the lineages concerned are closely related is contrasted with two where this is not so. The first instance involves an intrafamilial comparison of three members of the lacertid genera Meroles and Acanthodactylus, which show strong concordance in trait order and great similarity in their independently acquired traits. The other comparisons are of members of different families: Meroles anchietae (Lacertidae), Uma (Phrynosomatidae), Phrynocephalus arabicus (Agamidae) and Pristurus carteri (Gekkonidae). Here concordance in trait order is much lower and independently developed traits often show substantial differences in the various groups. The principal reason for the disparity in results appears to be the much longer and more varied separate histories of the lineages involved in the interfamilial comparisons before they finally entered aeolian sand. These historical differences result in particular independently acquired features developing much earlier in some lineages than others and in the development of phylogenetic constraints and proclivities that influence the detailed ways some environmental problems are solved. Finally, no evidence could be found that traits which evolve in similar sequences in different lineages are developmentally interconnected.

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The effects of previous history on adaptation can be studied in situations where several taxa have been independently exposed to a well-specified problem posed by their selective regimes. This approach was applied to the ways surface-dwelling dune lizards dive rapidly into loose sand when evading predators. Lacertids of the genus Meroles use all limbs and serpentine body and tail movements, behaviour which arose directly in the context of predator evasion in sandy habitats. The agamids, Phrynocephalus and Agama etoshae employ lateral body oscillations and descend vertically, an aberrant method resulting from previous evolution of a blunt snout. The scincid, Scincus and gerrhosaurid, Angolosaurus, both use high amplitude sinusoidal movements of the body and tail, which apparently evolved in a common ancestor of these taxa long before being co-opted to use in sand. In contrast, the scincid, Mabuya acutilabris, holds the body straight, a method that probably originated in the context of concealment at the end of activity. In the phrynosomatid, Uma, the head oscillates up to 60 times per second, the forelimbs are folded back and hindlimb thrust is supplemented by scales on the upper arms acting like ratchets. Some components of this method originated in the context of slow concealment in firm substrata at the end of activity periods, a basic pattern later co-opted for rapid diving in compact sand with modification of the snout to form a drill. Finally, this elaborated mechanism was transferred to loose sand with further behavioural and morphological change. Rapid sand burial by Phrynosoma species has the same origin as that in Uma but, like Phrynocephalus, includes a strong vertical component. It too is associated with a blunt snout which, however, arose after initial burial behaviour developed, not before. These results suggest that, once related lineages have diverged, differences may still accumulate even in similar situations. Sand diving also exhibits striking cases of convergence and provides an example of how function can be used to polarize characters, suggest the situations in which derived states arose and indicate their likely order of change.

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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 sclerotic ring consists of several bones that form in the sclera of many reptiles. This element has not been well studied in squamates, a diverse order of reptiles with a rich fossil record but debated phylogeny. Squamates inhabit many environments, display a range of behaviours, and have evolved several different body plans. Most importantly, many species have secondarily lost their sclerotic rings. This research investigates the presence of sclerotic rings in squamates and traces the lineage of these bones across evolutionary time. We compiled a database on the presence/absence of the sclerotic ring in extinct and extant squamates and investigated the evolutionary history of the sclerotic ring and how its presence/absence and morphology is correlated with environment and behaviour within this clade. Of the 400 extant species examined (59 families, 214 genera), 69% have a sclerotic ring. Those species that do not are within Serpentes, Amphisbaenia, and Dibamidae. We find that three independent losses of the sclerotic ring in squamates are supported when considering both evolutionary and developmental evidence. We also show that squamate species that lack, or have a reduced, sclerotic ring, are fossorial and headfirst burrowers. Our dataset is the largest squamate dataset with measurements of sclerotic rings, and supports previous findings that size of the ring is related to both environment occupied and behaviour. Specifically, scotopic species tend to have both larger inner and outer sclerotic ring apertures, resulting in a narrower ring of bone than those found in photopic species. Non-fossorial species also have a larger sclerotic ring than fossorial species. This research expands our knowledge of these fascinating bones; with further phylogenetic analyses scleral ossicles could become an extremely useful character trait for inferring the behaviour of fossil squamates.

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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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Lizards communicate with others via chemical signals, the composition of which may vary among species. Although the selective pressures and constraints affecting chemical signal diversity at the species level remain poorly understood, the possible role of diet has been largely neglected. The chemical signals of many lizards originate from the femoral glands that exude a mixture of semiochemicals, and may be used in a variety of contexts. We analyzed the lipophilic fraction of the glandular secretions of 45 species of lacertid lizard species by gas chromatography/mass spectrometry. The proportions of nine major chemical classes (alcohols, aldehydes, fatty acids, furanones, ketones, steroids, terpenoids, tocopherols and waxy esters), the relative contributions of these different classes (‘chemical diversity’), and the total number of different lipophilic compounds (‘chemical richness’) varied greatly among species.We examined whether interspecific differences in these chemical variables could be coupled to interspecific variation in diet using data from the literature. In addition, we compared chemical signal composition among species that almost never, occasionally, or often eat plant material. We found little support for the hypothesis that the chemical profile of a given species’ secretion depends on the type of food consumed. Diet breadth did not correlate with chemical diversity or richness. The amount of plants or ants consumed did not affect the relative contribution of any of the nine major chemical classes to the secretion. Chemical diversity did not differ among lizards with different levels of plant consumption; however, chemical richness was low in species with an exclusive arthropod diet, suggesting that incorporating plants in the diet enables lizards to increase the number of compounds allocated to secretions, likely because a (partly) herbivorous diet allows them to include compounds of plant origin that are unavailable in animal prey. Still, overall, diet appears a relatively poor predictor of interspecific differences in the broad chemical profiles of secretions of lacertid lizards.

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

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

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

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

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A checklist of the lizards of the Cape Province, South Africa is presented. A total of 143 species and subspecies is recognized. The taxonomic status of no less than 84 (59,1%) of these has changed since the last review of the Cape lizards by FitzSimons (1943). Comments on the distribution and taxonomic status of problematic groups are included.

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

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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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Southern Africa has the richest reptile diversity in Africa, with a fauna that currently exceeds 490 species. Present rates of discovery, which for lizards are still comparable to those in the early phases of exploration, indicate that the fauna may approach, if not exceed, 600 species. Lizards form the dominant component (60.9%) of the reptile fauna. The 578 recognised taxa (species and subspecies) were described by 101 authors, of which 12 authors were responsible for 12 or more taxa and together named 68.9% of the total taxa. The five most productive authors were, in order: A. Smith, W. Peters, D. Broadley, J. Hewitt, and V. FitzSimons. The contributions of these authors, the growth in herpetological studies in the last 25 years, and the importance of regional surveys in the development of biogeographic models, are summarised. Over 50 species of reptile have very restricted distributions (less than 3 quarter-degree grid squares) and may be of conservation concern. Despite national rhetoric evincing concern for the biodiversity crisis, there has been a recent decline in herpetological posts and manpower.

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

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

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

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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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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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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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We characterised behavioural variation between adult male, adult female and juvenile Meroles cuneirostris, a diurnal lacertid lizard endemic to the Namib Desert. Variation in microhabitat preference was significant between age classes, as adults spent more time underneath vegetative cover than juveniles. Movement patterns varied between demographic classes as juveniles exhibited movements of higher average durations than adults overall, and spent a greater percentage of time moving than adult females. Juveniles turned their heads more often than adults; all individuals scan their surroundings more frequently in the open sand and near vegetation. An analysis of foraging behaviour indicates that M. cuneirostris exhibits relatively few movements per minute (MPM) and a wide range of percentage of time spent moving (PTM), making it difficult to categorise this species as either an ambush or active forager. Furthermore, intraspecific variation in foraging behaviour within this species exists, as adult males and juveniles exhibited higher PTM values than adult females.

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

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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 endocrine pancreas from 2 genera of lacertid lizards (Pedioplanis and Meroles) was investigated immunocytochemically for the presence of immunoreactivity to mammalian antisera to insulin (I), glucagon (G), pancreatic polypeptide (PP), peptide tyrosine tyrosine (PYY), neuropeptide tyrosine (NPY), somatostatin 14 (SRIF 14) and somatostatin 28 (SRIF 28), pancreastatin (Pst), galanin (Gl), oxytocin (OT). Cells immunoreactive (IR) to all the antisera used, and nerve fibers IR only to anti-galanin were found. Moreover, three types of colocalized immunoreactivities were detected: type 1 (PP/PYY/NPY), type 2 (G/PP/PYY/NPY), and type 3 (G/PYY/NPY/Pst).

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Comparative analyses were carried out about the variability of the pileal shields of different species belonging to the family Lacertidae. The results of the comparisons have been evaluated in respect to the phylogenetical relationships existing between the different genera and species of the family.

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The phenotype of an individual has often been used as the descriminating factor in distinguishing species. However, with the advent of more precise molecular techniques, the genotype of species is increasingly being used as the preferred method in taxonomic classifications. Many taxa have recently been demonstrated to be incongruent in terms of their genetic and morphological groupings, and this may due to the influence that the environment may have on the morphological and functional aspects of a species. Selective pressures often act upon the performance of a species within a particular habitat first, and then selection for the morphological characters that allow for optimal performance occurs. Should genetically disparate species inhabit a particular environment, convergence in morphologies and performance may evolve. Historically, lizard species descriptions were based primarily on external morphologies, and thus misclassfication of species may have occurred due to mistakenly grouping species with convergent morphologies together. In the current dissertation, the links between morphology, performance capacities, diet and behaviour is explored in comparison to the environment and genetic relationships of southern African lacertid lizards. The performance capacities and associated morphological traits were expected to be more closely linked with the environment, and not closely linked with genetic relationships. To investigate these expectations, a multidisciplinary approach was taken, and genetic, morphological and performance analyses were done and compared with dietary behavioural and environmental analyses. In the first chapter, the link between habitat openness and the lizard bauplans is investigated and the presence of convergent morphologies within this group of lizards is uncovered. These convergences are shown to have resulted in misclassification of two lacertid species, and taxonomic revisions within the family are discussed. The second chapter explores the link between performance and associated morphological traits, and the dietary composition of the members of the Nucras genus. The third chapter identifies the link between the predator escape strategies employed by the members of the Meroles genus, and their morphologies and performance capacities. The fourth chapter explores the intraspecific, inter-population differences in morphologies and investigates the link between the morphological groupings and the population genetic groupings within Pedioplanis lineoocellata. The final chapter identifies whether adaptation to a novel habitat can occur over a relatively short period of time, and the morphological traits, functional aspects, and population genetic structure is investigated in conjunction with environmental analyses of vegetation and substrate between the populations of Meroles knoxii. It was concluded that the morphological and functional aspects of the southern African lacertid lizards are more closely related to the environment, particularly the microhabitat structure, than to their genetic relationships, and that future work using this group of lizards should involve a multidisplinary approach as different selective pressures are playing a role in shaping the morphologies and performance capacities of these lizards, compared to those that are acting upon the genotypes of the lizards.

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

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

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Meroles knoxii is a medium-sized lacertid lizard endemic to the sandy regions of south-western South Africa. In the year 2000, three individuals were translocated a distance of ca. 18km, from a natural population in Phillipi to a dredge spoils site within Zandvlei Nature Reserve, Western Cape Province. Since the introduction, the Zandvlei population has grown in terms of numbers, however whether any changes, genetic or morphological, have been affected over the past decade is unknown. The ND4 mitochondrial gene was sequenced to investigate the genetic diversity within and between the populations, and a suite of morphometric characters were investigated using multivariate analyses to examine morphological differences. The source population had higher genetic diversity (5 haplotypes in 17 individuals) than the introduced population (2 haplotypes in 66 individuals) and an analysis of molecular variance indicated significant allele frequency differences between populations. Males were larger than females in both populations, but relative body dimensions (corrected for size) were not significantly different. Between populations, there were significant differences for limb dimensions: individuals from the Phillipi population tended to possess longer hindlimbs, shorter forelimbs and shorter digits, compared to Zandvlei. These differences may be an adaptation to differing substrates at the two sites, and/or perhaps due to a shift in foraging strategys. In the past decade, the morphology of the Zandvlei population appears to have diverged from the source population in response to the new habitat, whilst the genetic diversity of the population has remained low.

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

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Successful escape from predators may involve the use of multiple tactics. The wedge-snouted desert lizard (Meroles cuneirostris) flees from predators through a series of discrete moves with each move representing a specific manoeuvre type. By simulating the approach of a predator, we examined the role of sex and age (adult vs. juvenile) on the manoeuvre types used during escape, as well as the relationship between the number of moves needed to escape and the number of manoeuvre types employed. The eight defined manoeuvre types were used by all demographic groups, though there were differences among groups in the tendency to use certain manoeuvre types. In general, there was a strong difference in how adults and juveniles fled from predators. The number of manoeuvre types used by a lizard tended to increase with the number of moves required to escape and adults more readily added new manoeuvre types to an escape sequence. Demographic differences in escape behaviour might result from differing predation pressures incurred by juveniles and adults, and might also be related to the ontogeny of escape behaviour.

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The shovel-snouted sand lizard, Meroles anchietae, is a small lacertid that inhabits the aeolian sand dunes of the Namib Desert. We conducted focal observations to characterize the movement patterns of adult male, adult female, and juvenile M. anchietae in their preferred habitat: dune slip faces. Movement varied considerably among demographic classes. Both adult males and females made longer moves than juveniles, but males moved less frequently than females or juveniles. Males exhibited shorter path lengths and shorter net displacements than females or juveniles. Turn angle distributions varied among classes, with females differing from the other two classes. For all three classes, the distribution of movement directions differed from uniform, with lateral moves across the slip face being most common. Movement across the slip face reflects both the ease with which lizards can navigate the substrate and behavioral factors such as foraging strategy and social interactions. Distance and direction pairings differed both from random expectations and among the demographic classes. Movement characteristics indicate that demographic classes respond to the environment differently, even while using the same habitat.

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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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Risk assessment and behavioral responses to predation can depend on demographic and environmental factors. We studied the escape behavior of the sand-diving lizard Meroles anchietae in the Namib Desert, using simulated predator approaches and measuring latency to burying in sand. Lizards showed a clear preference for burying on a slipface. Flight initiation distance was largely influenced by the starting distance separating the lizard and pursuer, and whether the animal was initially sighted on or off a slipface. In general, longer starting distances were associated with longer flight initiation distances. The total flight distance covered by lizards before burying was inversely related to body size, and positively related to initial distance from a slipface crest. Distance from a slipface crest was associated with increased total flight distance, most dramatically for those initially sighted on a dune slipface. Even when shelter is ubiquitous, sand-dive patterns depend on location on a dune and body condition.

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

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The reproductive cycle of the spotted sand lizard, Meroles suborbitalis was studied from a histological examination of gonads. The reproductive cycle is prolonged with males undergoing spermiogenesis in all months examined. Females with reproductively active ovaries were found in all months except July. Histological evidence is presented (corpora lutea and yolk deposition in the same ovary) that more than one clutch can be produced in the same reproductive period. Females undergo a quiescent period between clutches. Regression analysis revealed a significant correlation between female body size and clutch size. Mean clutch size for 55 gravid females was 3.98 [+ or -] 1.01 SD, range 1-6. One and two eggs are new minimum clutch sizes for M. suborbitalis. The smallest reproductively active male measured 45 mm SVL; the smallest reproductively active female measured 48 mm SVL. The prolonged reproductive cycle of M. suborbitalis resembles that of Meroles anchietae.

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

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The reproductive cycles of two narrowly sympatric lacertid lizards from the Namib Desert of Namibia (South-West Africa) were investigated. Aporosaura anchietae is capable of continuous reproductive activity for prolonged periods (Jan 1976-Feb 1977). Reproductive activity declined sharply in March 1977, but quickly increased in April. Recovery was completed by June 1977, and reproduction continued into December 1977 when the study was terminated. Continuous reproduction for more than 1 yr is typical of tropical lizards, but has not been reported previously for a desert species. Causes of the March 1977 reproductive decline are not totally clear, but appear to be related to decreased rainfall, to lower productivity of insects, and to lower levels of stored fat. The average clutch of 85 females was 1.3 eggs (range 1-2), and 2-4 clutches are produced yearly. Meroles cuneirostris has a reproductive cycle typical of temperate zone species, with spermiogenesis occurring May-February (spring-summer), followed by autumnal regression (March) and then recrudescence (April). Oviducal eggs were found over a 5-mo period (Sep-Mar). Clutch size of 29 females averaged 2.9 eggs (range 1-4), and females can produce two clutches each year. Both species have seasonal fat cycles typical of temperate zone lizards, in which fat bodies enlarge in autumn and are depleted by spring, but the relative amounts of fat stored by each species differ considerably.

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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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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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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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Long-term ecological research (LTER) is invaluable for understanding environmental processes, particularly variability and drought, in arid countries and as support for effective natural resource management in the drylands. The Gobabeb Training and Research Centre undertakes various long-term monitoring focused on, inter alia, climate and the biophysical environment. Examples are given of the results of this LTER and how they could be used to serve social and environmental functions in the drylands.

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

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

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

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

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

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

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

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

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

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

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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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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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In both December 1992 and September 1995 I travelled through South Africa and Namibia. In the Daan Viljoen park in Windhoek Agama planiceps, Mabuya spilogaster and Pachydac- tylus bibroni were found. Pedioplanis brevi- ceps was seen in trees and bushes of the Namib Desert while in the barer valleys Pedioplanis undata undata was observed. A Chamaeleo namaquensis was seen in a small bush. Other species which were recorded were M. spilogaster and Ptenopus garrulus macula- Ius. In the Kalahari Gemsbokpark only M. spi- logaster, Agama aculeata aculeata and Pelomedusa subrufa were seen, the latter after a shower. Pedioplanis undata inomata, Mabuya sulcata, Mabuya variegata, Platysaurus capensis, Agama anchietae, Pedioplanis namaquensis, Cordylus po/yzonus and Pachydactylus bibroni were found in Fish River Canyon by the camp site. The tempera- ture can rise to 45°C over the day. The lizards seemed to go into shock when captured. In 1995 I spent a long time in Namaqualand. Here a lot of reptiles were found in a relative- ly small area. These included: Cordylus cataphractus, Cordylus polyzonus, Pediopla- nis lineocellata pulchella, Meroles suborbi- talis, Agama hispida hispida, Bitis arietans, Homopus signatus signatus and Chersina angulata. In the Mediterranean climatic zone and in the Karoo the following unusual species were recorded: Psammo- bates tentorius trimeni, Geochelone parda- lis and Pseudocordy/us capensis.

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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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The albumins from 41 species of the family Lacertidae representing a substantial part of genera as well as infrageneric groups of the collective genus Lacerta s.l. were investigated by means of the MCF technique. The data allow a chronological estimation of the most important radiation events and their correlation with paleogeographical facts. Our results are in remarkable contradiction to the phylogeny presented by ARNOLD (1989a) based mainly on morphological characters. The most important phylogenetic relationships are: 1. The genera Gallona and Psammodromus are already isolated from the other taxa since the Oligocene. We assess these main branches as subfamilies Gallotiinae and Lacertinae. 2. Lacerta s.str. and Lacerta subgenus Zootoca form the sister group of the remaining Lacertinae. 3. A colonization of Africa in the Lower Miocene has led to a separation in two lines, with mainly Eurasian and African members respectively. 4. ARNOLD`S (I.e.) `Ethiopian and advanced Saharo-Eurasian clade` proved to be a paraphyletic unit, one group of genera being more closely related to European taxa. All techniques applied to the systematics of Lacertidae hitherto are critically discussed. An area-time- hypothesis concerning the phylogeny of Lacertidae is presented. Key words: Lacertidae, phylogeny of; Gallotiinae subfam. nov.; Lacertinae subfam. nov.; micro complement fixation; albumin evolution.

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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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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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Two hundred twenty-two individual reptiles (11 families, 45 species) from 17 districts of Namibia were examined for endoparasites. Thirty-three (31 lizards, 2 snakes) individuals (15%) were found to harbor at least 1 species of helminth; 4 lizards harbored a multiple infection of 2 helminths, 1 lizard was infected with 3 species, and 1 lizard harbored a multiple infection of 5 species. One species of linstowiid cestode, 12 species of nematodes representing 6 families, and 1 species of cephalobaenid pentastomid were found in the herpetofauna surveyed. Twenty-seven new host and 8 new geographic records are documented for helminths of Namibian reptiles.

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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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Foraging behaviors exist along a continuum from highly sedentary, ambush foraging, to more continuous searching, or active foraging. Foraging strategies, or modes, are defined based upon locomotor behaviors (e.g. percent time moving, moves per minute). In lizards, traits correlated with ambush and active foraging have been of interest for some time; however, general patterns of correlated evolution between locomotor morphology and locomotor behavior have only recently begun to be quantified. In this study, variation in hindlimb morphology is investigated in a model group of lizard species that vary between active foraging and more sedentary (or mixed) foraging mode. Canonical variates analysis reveals that the two active foraging species occupy similar regions of the morphospace, while the two more sedentary species occupy different regions. The active foraging species have a narrow pelvis with shorter tibia and femora. The more sedentary species have a wide pelvis, long tibia and femora, and slightly longer metatarsals. Phylogenetic patterns of trait variation were examined through ancestral character state reconstruction and show morphological shifts in concert with foraging mode in these species. The observed shifts in locomotor morphology are discussed in light of published data on sprint speed and endurance in these species. Together, the data show that linking morphological variation to variation in stride length and stride frequency is critical to understanding the evolution of locomotor performance. Much more stride length and frequency data are needed among ambush, mixed, and active foraging species because these parameters, and their morphological components, are likely correlated with variation in food acquisition mode.

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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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Shovel-snouted sand dune lizards, Meroles anchietae, are reported to include much seed from grasses and fig marigolds in their diets year-round. This diet is quite unusual for a reptile, and invites investigation. We had an opportunity to examine the diet and to measure seed digestibility for M. anchietae living on dunes near Gobabeb, Namibia. Stomach contents taken harmlessly via esophageal cannulation in the field revealed that the average diet included 37% (dry mass basis) immature seeds, 61% arthropods and 2% green plant leaves and flowers. Captive lizards fed measured amounts of whole mature (dehisced) grass seeds, both with and without hulls, were unable to digest and assimilate any significant dry matter from them. Microscopic examination of seeds recovered from stomachs along with seed remains found in fresh fecal pellets from free-living M. anchietae indicated that most of the “seeds” apparently were soft, moist, somewhat green and immature when eaten, and may be better termed “ovules”. This food, perhaps eaten directly from the flowers of the plant, would be much more digestible and nutritious than mature, dry, shed (dehisced) seeds. We suggest that the seed-eating behavior of M. anchietae might be better described as herbivory than as granivory.

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The occurrence and form of sex chromosomes were investigated with the aid of C-banding and 4′-6-diamidino-2-phenylindole (DAPI) staining in 13 species of lacertid lizards. The results obtained show the presence in five species of a female heterogamety in which the two sex chromosomes have the same shape and size, but the W differs from the Z in being almost entirely heterochromatic. This condition is clearly similar to that found in some snakes and considered to be an early stage of differentiation of sex chromosomes by Singh et al. (1976, 1980). A more evolved condition may be that found in three other species in which the W is distinctly smaller than the Z. A third situation is that found in all Podarcis species which, even though they are considered to be among the more evolved species in the family, possess two sex chromosomes that are indistinguishable. In general, the situation in lacertids may be compatible with the hypothesis of sex chromosome evolution put forward by Singh et al. (1976, 1980). However a differentiation mechanism of this kind does not seem to be well established in lacertids, and is probably not the only mechanism that is in operation in this family.

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Ultraviolet (UV) vision and UV colour patches have been reported in a wide range of taxa and are increasingly appreciated as an integral part of vertebrate visual perception and communication systems. Previous studies with Lacertidae, a lizard family with diverse and complex coloration, have revealed the existence of UV-reflecting patches that may function as social signals. However, confirmation of the signalling role of UV coloration requires demonstrating that the lizards are capable of vision in the UV waveband. Here we use a multidisciplinary approach to characterize the visual sensitivity of a diverse sample of lacertid species. Spectral transmission measurements of the ocular media show that wavelengths down to 300 nm are transmitted in all the species sampled. Four retinal oil droplet types can be identified in the lacertid retina. Two types are pigmented and two are colourless. Fluorescence microscopy reveals that a type of colourless droplet is UV-transmitting and may thus be associated with UV-sensitive cones. DNA sequencing shows that lacertids have a functional SWS1 opsin, very similar at 13 critical sites to that in the presumed ancestral vertebrate (which was UV-sensitive) and other UV-sensitive lizards. Finally, males of Podarcis muralis are capable of discriminating between two views of the same stimulus that differ only in the presence/absence of UV radiance. Taken together, these results provide convergent evidence of UV vision in lacertids, very likely by means of an independent photopigment. Moreover, the presence of four oil droplet types suggests that lacertids have a four-cone colour vision system.

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

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

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

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A male expends 824 joules per day, more than twice the energy used by the smaller female (382 J day -1). Differences in field metabolism are due to mass, not sex. Most individuals of both sexes lost body mass and were in negative water balance during the summer experimental period. Feeding experiments demonstrated that seed-eating and fasting lizards lose weight at similar rates. The Assimilation Efficiency is lowest for seeds (0.52) and higher for beetle larvae (0.87). The energetic advantages of small female body size are discussed in relation to the Namib dune environment and the reproductive biology.

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Although similar in physical characteristics, dune ecosystems of the Namibian and North American Deserts have distinctive geological ages, regional climates and microenvironments. Specialist sand-diving lizards have evolved in each system albeit at different tempos and modes of speciation. Meroles anchietae (Lacertidae), and Gerrhosaurus skoogi (Gerrhosauridae) of the Namib Desert, and six taxa of Uma (Phrynosomatidae) inhabiting isolated dune systems across the North American Deserts have separately evolved convergent external morphologies, but differ in body mass, reproductive cycles, number and size of progeny, metabolic physiology and behavior. All are omnivores consuming variable proportions of vegetation including seeds along with insects that are part of detritus-based food webs. Populations of M. anchietae and Uma undergo dramatic density changes depending on annual surpluses or deficits of energy and water, mediated through unpredictable rainfall and prey availability. Unlike Namib lizards, which inhabit large contiguous dune landscapes, several species of Uma are seriously threatened by habitat loss and fragmentation from development and recreational activities. Harsh conditions common to all desert dune environments present similar challenges to species that live there, but differences in their age, climate and geographic extent offer exceptional opportunities for understanding evolution and ecosystem structure and function.

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

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

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

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

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Climate change is considered to be one of the greatest threats to species and ecosystems globally and is likely to contribute to the rapidly increasing number of species extinction. In South Africa, these climatic changes have been noted and are thought to persist. Lizards, as ectotherms, are exceptionally vulnerable to changes in their thermal environments and could face even greater extinction risk if they lack the capacity to behaviourally mediate or rapidly adapt to changing thermal environments. Species distribution models have only recently started incorporating genetic and physiological mechanistic variables to more accurately predict species responses to climate change. This study investigates genetic and physiological traits in order to elucidate genetic patterns and thermal traits that could aid in more accurately predicting the climate change responses of a southern African lacertid lizard. In Chapter 2, I investigated the phylogeographic occurrence of Meroles knoxii along the west coastal margin of southern Africa, with special focus on the southern mesic extent of the distribution range. Phylogeographic and population genetic analyses consistently retrieved three distinct genetic clades (north, central and south) that occur allopatrically on a north-south axis along the coastline. Body size differences occur between the northern and southern clades with the northern xeric clade displaying significantly larger body sizes than the southern mesic clade, suggesting local adaptation to these environments in conjunction with the genetic differentiation observed. The southern clade exhibited no genetic differentiation at a small spatial scale and is thus considered a single population. In Chapter 3, the thermal sensitivity of several traits of M. knoxii was investigated comparing two sites within the southern clade to determine whether and which traits are variable or conserved at a small spatial scale. Selected body temperatures differed significantly between sites. However, these differences are not considered biologically relevant in this study. Critical thermal limits, resting metabolic rate and total evaporative water loss did not differ significantly between sites and is considered a conserved thermal trait at this small spatial scale. In addition, the potential trade-off of thermal performance traits (sprint speed and stamina) was investigated for this ambush predator at one site, Zandvlei Nature Reserve. As expected, M. knoxii displayed optimal sprint speed capacity at high test temperatures and optimal stamina at lower test temperatures. This study aims to illustrate the importance of incorporating ecologically relevant mechanistic variables into species distribution models to more accurately predict species potential responses to future climate change.

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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.

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

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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.

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Although the core temperature of lizards can vary with, for example, species, age, size, gender and season, they, in fact, maintain core temperature within an effective and safe range for biochemical and CNS processes. Desert dwelling lizards have evolved behaviors that minimize contact with dangerously hot sand, and to regulate the heat flow between the environment and their bodies. Shuttling between sun and shade, and digging are effective, but in certain situations it is disadvantageous to move, and instead, modification of posture in situ is employed. The postures include thermoprotective thermoregulation, as when a lizard lifts feet and/or legs and tail off the surface to avoid getting feet burnt, and thermoregulation when it stands on all legs with the torso lifted high off the substrate to minimize heat flow from the substrate. These behaviors can at times conflict, as when it needs to support itself on the hot sand, while lifting the body to defend core temperature. Resolution of this conflict often is with a “thermal dance”. To analyze this “thermal dance” of the Wedge-snouted lizard we experimentally investigated the core temperature at which the transition from thermoprotection to thermoregulation occurred. To quantitatively assess the behaviors, numerical score systems were developed for thermoprotection, P0-4 and thermoregulation, R1-3. During the southern hemisphere summer of 2011, two female lizards, weighing 4 g and 9 g, were captured and implanted with temperature transponders. Computerized control of the substrate temperature and simultaneous records of core temperature and videos of behavior were accomplished using an inexpensive solar-powered portable field laboratory. The system enabled arbitrary and rapid changes in substrate temperature, which allowed us to separate time from core temperature as the controlling variable of the behavior. Our preliminary results show that there was a specific core temperature at which either of the lizards adopted thermoregulatory posture R3, >39.5°C and >41.5°C for the lizard with the higher and lower weight, respectively. The slopes of core temperature rise during the test program were similar for both lizards, thus the size difference did not affect the independent variable. Preconditioning with a higher initial substrate temperature effectively shifted the distribution of core temperatures during test. The simultaneous recording of core temperature and behavior without manually manipulating the lizard provides many opportunities for exploring behavioral thermoregulation. This compact and inexpensive laboratory setup that was developed is appropriate for student work in places with limited resources.