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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 life history of an organism is the combination of age-specific survival probabilities and fecundities it displays in its natural environment. Hence, an organism`s life history is characterised by its age and size at maturity, frequency of reproduction, clutch or litter size, size of eggs and hatchlings, and survivorship at different life stages (as embryos, neonates, immatures, adults). Variation in these traits can be studied at different levels: within a population, among populations of a single species, and among different species. I here give an overview of studies that explored life history variation in European lacertid lizards.

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Oganismal performance abilities occupy a central position in phenotypic evolution; they are determined by suites of interacting lower-level traits (e.g., morphology and physiology) and they are a primary focus of natural selection. The mechanisms by which higher levels of organismal performance are achieved during evolution are therefore fundamentally important for understanding correlated evolution in general and coadaptation in particular. Here we address correlated evolution of morphological, physiological, and behavioral characteristics that influence interspecific variation in sprint speed in a clade of lacertid lizards. Phylogenetic analyses using independent contrasts indicate that the evolution of high maximum sprinting abilities (measured on a photocell-timed racetrack) has occurred via the evolution of (1) longer hind limbs relative to body size, and (2) a higher physiologically optimum temperature for sprinting. For ectotherms, which experience variable body temperatures while active, sprinting abilities in nature depend on both maximum capacities and relative performance levels (i.e., percent of maximum) that can be attained. With respect to temperature effects, relative performance levels are determined by the interaction between thermal physiology and thermoregulatory behavior. Among the 13 species or subspecies of lizards in the present study, differences in the optimal temperature for sprinting (body temperature at which lizards run fastest) closely matched interspecific variation in median preferred body temperature (measured in a laboratory photothermal gradient), in- dicating correlated evolution of thermal physiology and thermal preferences. variability of the preferred body tem- peratures maintained by each species is, across species, negatively correlated with the thermal-performance breadth (range of body temperatures over which lizards can run relatively fast). This pattern leads to interspecific differences in the levels of relative sprint speed that lizards are predicted to attain while active at their preferred temperatures. The highest levels of predicted relative performance are achieved by species that combine a narrow, precise distribution of preferred temperatures with the ability to sprint at near-maximum speeds over a wide range of body temperatures. The observed among-species differences in predicted relative speed were positively correlated with the interspecific variation in maximum sprinting capacities. Thus, species that attain the highest maximum speeds are (1) also able to run at near-maximum levels over a wide range of temperatures and (2) also maintain body temperatures within a narrow zone near the optimal temperature for sprinting. The observed pattern of correlated evolution therefore has involved traits at distinct levels of biological organization, that is, morphology, physiology, and behavior; and trade- offs are not evident. We hypothesize that this particular trait combination has evolved in response to coadaptational selection pressures. We also discuss our results in the context of possible evolutionary responses to global climatic change.

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Mitochondrial DNA analysis indicates that Podarcis vaucheri is a species complex with one clade inhabiting both north and south shores of the Strait of Gibraltar and one clade restricted to North Africa. While each clade exhibits differing morphology, allozyme analysis suggests varying degrees of reproductive contact among populations within clades. Ancestral P. vaucheri appears to have been restricted to insular areas of the Betic-Rif Massif and mainland Africa during Miocene, with major lineage differentiation occurring during Pliocene. Our analysis further confirms that Podarcis atrata warrants species status and suggests that it may be more widely distributed than previously reported.

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In the essay the finding and some morphological characteristics of a melanic example of Podarcis hispanica atrata found on the Columbretes archipelago (Castellón, Spain) is described.

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The incidence of cannibalism in the lizard Podareis hispaniea atrata in the Columbretes islands (Castelló de la Plana, Spain) under natural and captive conditions is described. Adult male lizards can ingest one hatchling in approximately four minutes. Hatchling digestability appeared to be very high.

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This study reports some observations on the predation 01 lizards (Podareis hispaniea atrata) by scorpions (Buthus oeeitanus), as well as on the predation 01 scorpions by this lizard species in the Columbretes islands (Castellion, Spain).

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This paper reports on the selection of substrate temperatures at oviposition sites by female lizards Podarcis hispanica atrata under laboratory conditions. Seven females deposited 11 clutches (a total of 34 eggs) in very small areas, representing 20 % of the available surface. The mean temperature of the sites used for egg laying was 25.7°C. Results are compared with incubation temperatures of the same species under natural conditions (Columbretes islands, Mediterranean, Spain).

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We studied aspects of the thermal biology and microhabitat selection of the endangered lizard Podarcis hispanica atrata during autumn in the field and laboratory. Body temperatures (T b ) of active lizards were within a narrow range, were largely independent of ambient temperatures, and exhibited little diel variation. Activity T b s largely coincided with the selected temperatures maintained in a laboratory thermogradient and with T b s that maximize running performance. Alternation of basking with other activities and shuttling between sun and shade were obvious aspects of thermoregulatory behaviour. Lizards shifted microhabitat use throughout the day. During early morning and late afternoon, basking lizards were restricted to rocky sites surrounded by shrubs. Near midday lizards used a wider array of microhabitats, and many moved in open grassy sites. Juveniles maintained lower activity T b s, had lower selected temperatures, and basked less frequently than the adults. Juveniles occupied open grassy patches more often than the adults. We discuss the relevance of our results for the conservation of this extremely rare lizard and the management of its habitats.

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The world range of the lizard Podarcis hispanica atrata is retricted to the Columbretes archipelago in the Mediterranean. We examined its actual distribution, abundance and some aspects of its natural history. Lizards were found in four islets (combined area c. 20 ha). Densities on the largest islet (13 ha) are high (> 600 lizards/ha), at least in favourable habitats. Population sizes on the smaller islets are extremely small (< 200 individuals). A considerable number of juvenile lizards was found in all populations. We report new information on body length distribution, sexual dimorphism, tail break frequency, escape behaviour, and diet composition. Recommendations for the conservation of this lizard and the improvement of its habitat are given and discussed in relation to landscape management programmes.

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We report reproductive characteristics (timing of sexual maturity, clutch frequency, clutch size, egg and hatchling sizes) of the Island Lizard Podarcis atrata. Reproductive performance was related to female size. The larger females initiate reproductive activities early in the season and produce two to four clutches annually, whereas the smaller individuals postpone reproduction until the season is well advanced and lay only a single clutch. Clutch size increased with female length and was slightly lower for clutches laid during June–July than for those produced during May. Among-clutch differences in egg mass were negatively correlated with clutch size, and this relationship is independent of female size. Larger clutches are also composed of less elongated (i.e., rounder) eggs than are smaller clutches, suggesting that the phenotypic trade-off between egg size and numbers is induced by limitations posed by the females` body volume, rather than by restrictions of energy availability. Comparison of reproductive traits of P. atrata to those of the closely related P. hispanica and P. bocagei indicates that the increase in body length during the evolutionary divergence of P. atrata was not associated with an increase in clutch size. This provides a clear exception to the general pattern found in lacertid lizards.

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Sequence data derived from a 306 bp fragment of mitochondrial cytochrome b and molecular variance estimates were used to investigate the genetic population structure of the endangered and endemic lizard Podarcis atrata of the Columbretes archipelago (Mediterranean, Spain). Our results show a very high and significant among-population genetic differentiation. FST values and phylogenetic analyses confirm the evolutionary distinctiveness of P. atrata populations, suggesting that the populations of these islands deserve special protection measures. The populations of the two islands Columbrete Grande and Mancolibre are less differentiated than those of Foradada and Lobo, and seem to have retained mainland haplotypes. This situation needs further attention as the origin of the mainland haplotypes is still unclear. If they are a result of recent introductions from mainland specimens, then they may represent a threat to the endemic lizards of the Columbretes islands.

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Endemic species and island populations are particularly prone to extinction. For this reason, their identification and protection is particularly important. Podarcis hispanica atrata is an endangered and endemic lacertid confined to the Columbretes Islands (19 ha, Mediterranean Sea, 39 degree 54`N, 0 degree 41`E, Spain). The status and nomenclature of P. h. atrata has a confused taxonomic history, but currently the taxon is considered as P. h. atrata. Populations of P. h. atrata differ from populations of P. h. hispanica in morphology, physiology, behavior, and life history. Because these differences may be ecogenetic, that is, habitat differences caused rapid adaptational change, this evidence alone is not sufficient enough to determine the taxonomic status of P. h. atrata. In this study, we used putatively neutral molecular markers (mitochondrial DNA sequences) to assess degree of divergence among populations of P. h. atrata relative to closely related taxa. The data are taxonomically relevant and provide a basis to develop conservation and management policies for this endangered lizard.

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In this study we present the first ecological data for the spiders Argiope lobata and A. bruennichi in Spain. We show data on density variation among two years (2004-2005), on the size of spiders and their webs, on sorne characteristics of the vegetation occupied by the two species, and on sorne aspects of their behaviour. The study has been conducted in the Columbretes islands (Mediterranean sea, Spain), taking the advantege of the recent colonization of the main island (Columbrete Grande, 13 ha) by the two spider species. We also discuss about the possible effect that such colonization could have on the endemic fauna of the island, particularly on the lizard Podareis atrata.

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Juveniles of a variety of lizard species exhibit bright tail colors that contrast clearly to the cryptically colored body. The `predator escape` hypothesis suggests that bright tail colors deflect the attack of a predator towards the lizard`s tail, which can be autotomised, and hence increase the probability of surviving a predatory attack. Although this hypothesis is widely accepted, surprisingly few empirical data exist to support it. Here, we examined the relative frequencies of predatory attack on plasticine replicas of juvenile lizards in the genus Podarcis with either green or brown tails in nine areas of Spain. Replicas with bright green tail color experienced, over a one-week period, the same rates of attack by birds and other predators as replicas with cryptic brown tails. However, the proportion of replicas that showed bill markings on the tail only was highest for the green-tailed replicas. In contrast, the frequency of predatory attacks towards the head or body was similar in the two groups of replicas. Our experiment appears to support the classical prediction of the adaptive value of a green autotomic tail in lizards. However, lizard species with multiple tail colors may also represent alternative anti-predator strategies that may have arisen by different selective pressures between habitats. We also suggest that the evolution of bright tail coloration in juveniles of Podarcis as an antipredator mechanism may be favored by the correlated evolution of morphological, physiological, and behavioral characteristics

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To understand the dynamics of small populations in arid environments, particularly in small insular ecosystems, it is crucial to understand the interactions between species inhabiting these environments. Here we investigate the interactions between lizards and scorpions in a small arid insular ecosystem in the Mediterranean. Experimental observations suggest that scorpions are regarded as prey by lizards. However, the response of lizards was sex-dependent, with males being more likely to attack scorpions than females. This can be associated with the larger body and head size, and bite forces in males, presumably making scorpions a profitable prey. Predation on lizards by scorpions has been also documented, suggesting a classic case of cross predation.

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This study reports on an experiment designed to quantify potential predation by birds on the lizard Podarcis hispanica atrata in the Columbretes islands (Castellón, Spain). We used plasticine replicas to examine predation risk of replicas as a function of proximity to vegetation and to potential predators, and to investigate the seasonal variation in patterns of predation. Predation on replicas was very high and intensive within only four days, and differed between study areas and seasons. Predation was more intense when replicas were closer to nests of gulls and far from vegetation. The Yellow-legged Gull (Larus cachinnans michaellis) was identified as the major species responsible for predation on lizard replicas.

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In this study we document the spatial and temporal variation in the density of two orb-web spiders (Argiope lobata and A. bruennichi) in the Natural Park of Columbretes islands (Castellón, Spain) during 3 con- secutive years (2004-2006). The masive presence of these species was detected for the first time in 2004 in the main island Columbrete Grande (13 ha). From then, we followed their population size. It is very important to document temporal fluctuations in the den- sity of invader species, mainly in small islands occupied by endemic vertebrate and invertebrate species that may suffer higher predation and competition for food.

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This paper reports the development of u new technique that may help to increase the number of lizards in areas where scarcity of oviposition sites constitutes the major limiting factor. We have created arttjicial egg-laying sites for the endangered subspecies of lizard Podarcis hispanica atrata in the Columbretes archipelago. Our results demonstrate that such urtiJcia1 sites were quick1y accepted bv the lizards us areas for basking und burrowing. Only one container was used for oviposition by one female, but the physical conditions in the artificial sites allowed successful development in 83’% of the eggs which were experimentally placed in them. Additional studies will be required to improve this technique and to determine if it might be applicable to other lizard species.

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We report the effects of incubation temperature on the duration of incubation and hatchling size in the insular lizard Podarcis hispanica atrata. Freshly-laid eggs were placed in artificial nests that were exposed to a natural cyclical variation of microclimate. We monitored substrate temperatures and egg size throughout the incubation period, and measured hatchling size at birth. The mean incubation period was 54 days at average incubation (substrate) temperatures that ranged from 23.5 to 26.5 C. We found a negative relation between the duration of incubation and mean incubation temperature. Overall survival of eggs to hatching was high (83%), even though eggs were frequently exposed for short periods (1-5 h) to high substrate temperatures (>35 C). We found no effect of duration of incubation or incubation temperature on the size of hatchlings.

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The lizard Podarcis atrata, endemic to the Columbretes archipelago (Mediterranean, Spain) occupies very small islands characterized by extreme aridity and a reduced availability of potential insect prey. The results of an experimental study have shown that adult lizards offered individuals of Ligia italica and Armadillo officinalis (marine and terrestrial isopods, respectively) consumed at high frequencies; with males consuming them at significantly higher frequencies than females. The results are discussed in light of the importance of the inclusion of marine prey into the diet in arid insular ecosystems.

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The aim of the present study is to synthesise the available data on the occurrence of lacertid lizards on Mediterranean islands better to understand how far human influence is involved in the present distributional patterns of insular lacertid lizard fauna. At present, the Mediterranean islands are inhabited by several lacertid genera, including endemic species of the genera Algyroides (viz. fitzingeri), Lacerta [Archaeolacerta] (viz. bedriagae) and Podarcis (atratus, filfolensis, gaigae, lilfordi, milensis, pityusensis, raffonei, tiliguerta, waglerianus). Recently reported data shed new light on the relationships between these endemics and some continental species that have recently colonised the islands. The arrival of the latter might be directly related to the progressive human colonisation of these islands. The arising conservation problems are also considered.

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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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We studied the effect of habitat fragmentation on female reproductive investment in a widespread lacertid lizard ( Psammodromus algirus) in a mixed-forest archipelago of deciduous and evergreen oak woods in northern Spain.We captured gravid females in fragments (≤10 ha) and forests (≥ 200 ha) and brought them to the laboratory, where they laid their eggs. We incubated the eggs and released the first cohort of juveniles into the wild to monitor their survival. Females from fragments produced a smaller clutch mass and laid fewer eggs (relative to mean egg mass) than females of similar body size from forests. Lizards did not trade larger clutches for larger offspring, however, because females from fragments did not lay larger eggs (relative to their number) than females from forests. Among the first cohort of juveniles, larger egg mass and body size increased the probability of recapture the next year. Thus, fragmentation decreased the relative fecundity of lizards without increasing the quality of their offspring. Reduced energy availability, increased predation risk, and demographic stochasticity could decrease the fitness of lizards in fragmented habitats, which could contribute to the regional scarcity of this species in agricultural areas sprinkled with small patches of otherwise suitable forest. Our results showthat predictable reduction of reproductive output with decreasing size of habitat patches can be added to the already known processes that cause inverse density dependence at low population numbers.

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The introduction of alien species to islands by human activity can cause catastrophic consequences for small populations of island endemics. Hybridization between the endangered and endemic insular lizard Podarcis atrata (Boscá, 1916) from the Columbretes Islands (Mediterranean, Spain) and the common mainland lizard Podarcis hispanica (Steindachner, 1870) could potentially occur because mainland haplotypes have already been detected in the islands, the two species are closely genetically related, and the frequency of visitors to these islands is increasing. However, reproductive decisions of lizards are often mediated by species recognition mechanisms based on chemical cues. On the basis of this observation, even if some mainland P. hispanica lizards were introduced to the islands, interspecific recognition might make rare an eventual hybridization with the insular P. atrata. We examined interspecific chemical recognition between the insular P. atrata and the mainland P. hispanica. Our results showed that lizards of both sexes responded more strongly (i.e., directed a significantly higher number of tongue flicks) to scents of conspecific individuals than to scents of heterospecifics. Chemical recognition of conspecifics by endemic island P. atrata lizards may reduce the occurrence of hybridization with introduced mainland P. hispanica lizards and protect the insular gene pool.

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Chemical signals can be the basis of interspecific recognition and speciation in many animals. The Columbretes Islands wall lizard, Podarcis atrata is very close genetically to the mainland Iberian wall lizard Podarcis hispanica. However, a previous study suggested that chemosensory interspecific recognition would avoid reproductive interactions and hybridization between these two species. These results suggested that chemicals used in intraspecific communication might differ in composition and/or proportions between these two species. In this paper, we used gas chromatography–mass spectrometry (GC–MS) to characterize the chemical composition of the lipophilic fraction from femoral gland secretions of male P. atrata and P. hispanica. The analysis showed that chemicals found in femoral secretions varied in composition and proportions between species and between populations. Seven steroids and two unidentified waxy esters, were exclusive of P. atrata lizards from the islands. In contrast, nine steroids and other six compounds were only found in mainland P. hispanica. There were also differences in proportions of shared compounds between species. Moreover, all these differences were higher between P. atrata and P. hispanica than between any population of P. hispanica. Chemical differences might be consequence of genetic differences, but they could also be explained by adaptation to different habitats with different climatic conditions or diet resources. Compounds that are specific of each species, or differences in the pattern of compounds, could explain species recognition. Therefore, these results of chemical composition and previous studies of chemosensory recognition reinforce the fact that the genetic differences between P. hispanica and P. atrata may result in an effective reproductive isolation between these two taxa.

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Recent genetic works have suggested that the Iberian wall lizard Podarcis hispanicus (Steindachner, 1870) sensu lato may in fact be a species complex, yet many of its taxa have not been formally described. We redefine the nominotypical Podarcis [hispanicus] hispanicus sensu stricto using univariate and multivariate morphological analyses and pinpoint its geographical distribution. Podarcis [hispanicus] hispanicus is a small wall lizard characterized by a flattened head and body, the general lack of a masseteric shield, a striped dorsal pattern, the frequent bifurcation of the anterior part of the vertebral strip, the belly almost always white and the tail intense blue in young specimens. Its distribution is restricted to the Spanish Levant (provinces of Alicante, Murcia and Almeria).

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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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Sexual dimorphism of relative head size is a widespread phenomenon in lizards, males having larger head/trunk ratios than females. In an attempt to explain this sexual dimorphism several hypotheses have been formulated. The two most frequently cited ones are: 1) sexual selection acting on those structures important in intrasexual competition and 2) natural selection for reduction of food competition between the sexes. In the insular subspecies of Podarcis hispanica (P h. atrata) males tend to have significantly larger heads than similarly sized females. We here test an implicit assumption of the dietary divergence hypothesis, namely that an increase in head size results in an increase in gape width and/or bite force, thereby allowing the larger headed sex to exploit larger prey classes. Using a static bite force model, we calculated the magnitude of bite forces for given directions at given positions on the jaws and for different head sizes. We experimentally determined the hardness of three different prey items and compared the data to the maximal bite force produced by both sexes. Our results suggest an important difference in male and female bite capacity, which may bear significant ecological relevance, and are in agreement with the implicit assumption of the dietary divergence theory.

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Aim We discuss biogeographical hypotheses for the Mediterranean lizard species Podarcis and Teira within a phylogenetic framework based on partial mitochondrial DNA sequences. Methods We derived the most likely phylogenetic hypothesis from our data set (597 aligned positions from the 12S rDNA and phenyl tRNA) under parsimony, distance and maximum likelihood assumptions. Results The species usually included in Teira do not form a strongly monophyletic clade. In contrast, the monophyly of the genus Podarcis is rather well supported. Seven lineages are identified in the genus; in order of appearance within the tree, these are: the Balearic pityusensis and lilfordi pair, the sicula complex, a Tyrrhenian tiliguerta and raffonei pair, muralis, the Siculo-Maltese filfolensis and wagleriana pair, the Balkan group (erhardi, peloponnesiaca, milensis, melisellensis and taurica), and the Ibero-Maghrebian group (bocagei, atrata, hispanica and vaucheri). Conclusions The origin of the three European genera of lacertid assayed (Lacerta, Teira and Podarcis) is hypothesized to have occurred in the Oligocene. For Podarcis, a possible scenario of a Miocene diversification is derived from the sequence data, and the zoogeography of the lineages are discussed in relation to the palaeogeography of the Mediterranean. It is hypothesized that in the early history of the genus the main lineages separated by rapid, numerous and close events that produced a starting point very similar to a polytomy, hard to resolve by parsimony analysis of the data set.

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Comparisons among eight populations of Podarcis lilfordi, seven of Podarcis pityusensis (representative lizards of the Balearic Archipielago), and one of Podarcis hispanica atrata fro the Columbretes Islands, have been made from a morphological point of view, measuring 15 morphometric characters of the lizards. Cluster and discriminant analyses were obtained for males and females to show the relationships among the different populations and species. These analyses gave three groups: one of them with the most P. lilfordi populations, other with the most P. pityusensis populations, and a well seperated group with the P. hispanica atrata species. Some populations connect the groups of P. lilfordi and P. pityusensis. The possibility that P. lilfordi and P. pityusensis be two pattern of variation inside the same species instead of two well differentiated species is considered, altrough further studies are necessary.

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Whereas the range size of endangered species is undoubtfuly useful to predict risk of extinction, the role of their life-history characteristics is much less clear, and their effects may depend on the nature of the threatening factors. Such factors, for instance, are known to be different on islands and on the mainland. We used phylogenetically based statistical analyses to study the relationships among conservation status, insularity, range size, and life-history traits in a clade of Western Palaearctic lacertids including insular and continental species. These lizards are ecologically similar, but they show wide variation in life-history traits and vulnerability to extinction. Insular species of a given size had smaller clutches than mainland ones. Degree of threat was best predicted by a logistic regression including range size, insularity, clutch size, and the insularity × clutch size interaction. On the mainland, but not on islands, threatened species had smaller clutches than non-threatened ones. On islands, small clutch size is probably an adaptive trait, and it might predispose certain species to extinction, but the intrinsic characteristics of such species remain unclear. However, small clutch size was a good predictor of extinction risk on the mainland, having evolved most frequently in late maturing species from montane habitats in which climatic conditions limit their reproductive output and increase their vulnerability to stochastic hazards or habitat fragmentation.

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Aim: The Mediterranean basin has a long history of interactions between humans and biota, with multiple ancient and recent introductions of alien species. Such a multitude of introductions makes it difficult to distinguish between alien and native species but provides an excellent opportunity to investigate factors related to intro ‐ductions and long‐term persistence of alien species. In this study, we combined ge ‐netic and distribution data to identify the factors promoting the presence of alien reptiles on islands, considering human‐related, geographic and species features. Furthermore, we assessed whether the use of genetic evidence to identify alien spe ‐cies improves inference of the factors determining their distribution.Location: Mediterranean islands.Methods: We combined genetic data and distribution databases to obtain informa‐tion on biological traits and on the native/alien status of reptiles on >900 Mediterranean islands, and we gathered data on geographic and human features of islands. We then used spatially explicit generalized additive mixed models to identify the factors associated with the establishment of alien reptiles.Results: Alien reptile populations are more frequent on islands far from the native range and with large human population. Alien populations of reptiles that are able to feed on plants are particularly frequent. Traditional data sources underestimate the frequency of alien reptiles on Mediterranean islands, and using genetic evidence to assess the status of populations provided a more complete picture of the factors as ‐sociated with the presence of alien populations.Main conclusions: Humans are key drivers of the distribution of alien reptiles on Mediterranean islands, but the distributions are determined by a complex interplay between human activities, geographic factors and species features. Genetic data are essential for obtaining reliable biogeographic assessments of invasive species, par ‐ticularly in systems with a long history of human influence.

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The naming of species and of all systematic entities of living things are dynamic con- cepts. Through scientific research, changes in the systematics and names of amphibi- ans and reptiles are constantly being pro- posed, much to the chagrin of many profes- sional and amateur herpetologists. Yet most changes are necessary if taxonomy and systematics are to reflect evolutionary his- tory and phylogeny, rather than letting user–friendliness and conservatism prevail. The European herpetofauna and its taxo- nomy have received increasing attention through molecular (e.g. DNA) studies. Once most animal groups have been studied in this way, stability may be established. In the following pages, a concise overview of changes in the taxonomy of European amphibians and reptiles is presented. We have restricted ourselves to the geographi- cal boundaries of Europe, albeit excluding former Soviet states. Thus, politically Euro- pean areas in Asia (e.g. Cyprus and Greek islands in front of the Aegean Turkish coast) and Africa (e.g. Canary Islands and Ma- deira) have not been included. For a time frame we have used the species and names as presented in the well–known European field guide by ARNOLD (2002), although numerous changes were proposed and published prior to 2002. We refer to the cited literature for more comprehensive explanations. Only species or higher level changes concerning European taxa are listed. Subspecific changes and intraspeci- fic variability are noted only when contra- dicting long–established monotypy of a species, or when subspecies are being rejected. Vernacular names are mostly adopted from ARNOLD (2002). Some exo- genous species that are well–established and are reproducing on European soil, are included and are listed separately. Species believed to have been introduced to Europe over 100 years ago and persisting until today, have been included in the list of endogenous species. Many other non– native species have, however, been en- countered in the wild in Europe. Final content changes were made on De- cember 1, 2007. This type of update and the proposed species list will most likely be outdated at its date of publication. Further updating by means of a consecutive series of similar papers seems desirable.

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Biomechanical reflections suggest that lizards that have specialized in running should differ in parts of their morphological design from lizards that have specialized in climbing. Moreover, adaptation in one direction may conflict with performance in the other. We tested this assumed trade-off by measuring climbing and running performance in two subspecies of the Mediterranean lizard Podarcis hispanica. One subspecies, P. h. atrata, inhabits a number of small islets near the Spanish coast. It is mainly ground dwelling. The other subspecies, P. h. hispanica, was sampled on the mainland of Spain. It frequently occupies vertical elements within its habitat. Our data do not support the notion of a trade-off between both types of locomotion. Individuals of P. h. hispanica both run and climb faster than those of P. h. atrata. There is no difference between subspecies in ability to cling onto tilted substrates. Predictions on the morphology of both subspecies, inspired by biomechanical arguments, are not supported by our measurements.

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Locomotor behaviour varies between two subspecies of the Spanish wall lizard Podarcis hispanica. One subspecies inhabits the Columbretes islands, the other lives on the Spanish mainland. Size standardized voluntary speeds (as measured in unrestrained laboratory conditions) are lower in the island population (P. h. atrata) than in the mainland population (P. h. hispanica). Maximal running performance (when chased) is much higher in the mainland population than in the island population. High speed video recordings show that subspecies differ in gait characteristics: individuals from the mainland modulate running velocity primarily by modifying stride length, individuals from the island primarily by altering stride frequency. P. h. hispanica’s strategy for modulating speed probably allows this mainland subspecies to attain higher maximal speeds than the island subspecies P. h. atrata. Theoretical considerations suggest that at high speeds, P. h. hispanica’s running style is energetically more favourable, but this hypothesis awaits experimental verification. We suggest that the differencesin locomotion efficiency between the subspecies result from differences in predation pressure between the mainland and the island. The mainland study site has a higher predator diversity and offers less hiding opportunities to the lizards.

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We compared the behavior of two subspecies ofPodarcis hispanica lizards in cages that had been chemically marked by a saurophagous snake, the viperVipera latastei. One of the subspecies (P.h. atrata) has experienced a relaxation from predation pressure by this viper, as snakes were eradicated from the island it inhabits over 100 years ago. Nevertheless, individuals fromP.h. atrata responded to the snake`s chemicals similarly to individuals from a population ofP.h. hispanica, currently sympatric withV. latastei. Lizards exhibited more stress-indicating behaviors (foot shakes, tail vibrations, sudden starts), became less mobile, and tongue-flicked more while moving in a snake-inhabited terrarium than when in a clean, unfamiliar terrarium.

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We tested the hypothesis that an evolutionary trade-off exists between the capacity to run on level terrain and the ability to climb inclined structures in lacertid lizards. Biomechanical and physiological models of lizard locomotor performance suggest that the morphological design requirements of a ground-dwelling vs. scansorial life style are difficult to reconcile. This conflict is thought to preclude simultaneous evolution of maximal locomotor performance on level and inclined terrain. This notion has been corroborated by comparative studies on lizard species from other groups (Anolis, Chamaeleo, Sceloporus), but is not supported by our data on 13 species from the family Lacertidae. We found no indication of a negative association between maximal sprint speed of lizards over a level racetrack (indicative of ground-dwelling locomotor performance), on an inclined stony surface (indicative of climbing performance over rock faces) and inclined mesh surface (indicative of clambering performance among vegetation). Moreover, morphological characteristics associated with fast sprinting capacities (e.g. long hind limbs) apparently enhance, rather than hinder climbing and clambering performance. We conclude that in our sample of lacertid lizards, the evolution of fast sprinting capacity on level terrain has not inflicted major restrictions on climbing and clambering performance.