×

The lizard Podarcis carbonelli is an endangered species endemic to the Iberian Peninsula. One location where this species occurs is at the Berlengas Natural Preserve, an Atlantic archipelago off the coast of Portugal. These island populations are geographically separated from nearby mainland populations. The fundamental question is, are these insular individuals distinct from the mainland populations? Four localities were chose for comparison: two island populations and two nearby coastal populations. We assessed this question using three distinct approaches: molecular, morphological and physiological approach. We sequenced the 12S RNA, the mtDNA Control Region and the 7th intron of the !-fibrinogen gene and determined genetic diversity values as well as several parameters of population structure and differentiation. Individuals from these populations were also measured for several biometric characters and their blood lactate concentration was sampled. There was no genetic variation in both the mtDNA regions analyzed. The nuclear intron revealed high levels of genetic variation, with islands having in general lower values than the mainland regions. The four populations sampled had low levels of divergence; the populations of Berlenga and Peniche were the most distinct and the populations of Farilhão and Baleal were the most similar from the four populations sampled. Morphometric analyses revealed a different pattern of similarity among populations with the population of Farilhão being the only population statistically distinct from all other populations based on mass and SVL. Furthermore, island populations were in general more similar to each other than to mainland populations, with the exception of Berlenga males which in size are more similar to the Peniche males. The analysis of the blood lactate concentration revealed that the population of Peniche has significantly lower blood lactate levels than the populations of Farilhão and Berlenga. The lack of genetic differentiation found in the populations under study is most likely due to the recent divergence of these populations. Furthermore, the genetically most different populations (Berlenga and Peniche) are not the most distinct in terms of morphology, particularly the males. This suggests that genetic drift, the most likely mechanism behind the genetic differentiation seen, is not responsible for the morphological differences observed. The morphological differences seen can be attributed to: a possible difference in age of the individuals in each population; mechanisms of natural selection that are favoring specific phenotypes in each of the populations, or phenotypic plasticity. The differences in blood lactate levels found between the population of Peniche and the island populations can be attributed to differences in predatory pressure or home range size. It is suggested that the island populations are closely monitored due to their likely isolation, low mtDNA diversity and possible higher predatory pressure than initially predicted.

×

The last catalogue of the Reptile collection of the Museu Bocage dates back to 1972. The collections were lost in a fire 25 years ago, so it was necessary to analyse the effort of various donors, who offered the Museum a new collection. The evaluation of the sampling effort is important to gather information (on quantity and origin) and the various samples of the species of lacertid lizards present in the Museum and enables an operational and practical visual imaged of that information. The obtained results prove that the study of the sampling effort using ordinary kriging method is robust and accurate on identifying gaps (under or no sampled areas) and a helpful tool to fulfil them. Although beginning to the representative of the Portuguese fauna, the lacertid collection of the Museu Bocage needs major improvements given that it still does not illustrate the actual distribution of lacertid lizards in Portugal. In order to stand for modern standards, when complementing the existing collection we must take into account not only the information provided by the analysis but also conservationist concerns (not killing animals) and the establishment of co-partnerships with congener institutions as well. Nowadays Museums have the duty, more than ever, to keep their collections well housed, cared for and accessible to the scientific community.

×

On a herpetological trip to the north-west of the Iberian Peninsula, the authors were able to record a total of ten species of lacertid lizards along with other reptile species. In particular, the densely populated Portuguese Atlantic coast proved to be a species-rich lizard habitat.

×

We carried out a morphometric study of the skull throughout postnatal ontogeny in 14 species of Iberian lacertid lizards belonging to the genera Acanthodactylus, Algyroides, Psammodromus, Podarcis, Zootoca, Timon and Lacerta s. latu with the aim of elaborating a key of identification for the studies species. A total of sixty one characters showing interspecific variation are identified. The characters are defined in articulated and disarticulated skulls.

×

The phylogenetic relationships among the wall lizards of the Podarcis hispanicus complex that inhabit the south-east (SE) of the Iberian Peninsula and other lineages of the complex remain unclear. In this study, four mitochondrial and two nuclear mark-ers were used to study genetic relationships within this complex. The phylogenetic analyses based on mtDNA gene trees constructed with ML and BI, and a species tree using *BEAST support three divergent clades in this region: the Valencia, Galera and Albacete/Murcia lineages. These three lineages were also corroborated in spe-cies delimitation analyses based on mtDNA using bPTP, mPTP, GMYC, ABGD and BAPS. Bayesian inference species delimitation method (BPP) based on both nuclear data and a combined data set (mtDNA + nuclear) showed high posterior probabilities for these three SE lineages (≥0.94) and another Bayesian analysis (STACEY) based on combined data set recovered the same three groups in this region. Divergence time dating of the species tree provided an estimated divergence of the Galera line-age from the other SE group (Podarcis vaucheri, (Albacete/Murcia, Valencia)) at 12.48 Ma. During this period, the Betic–Rifian arc was isolated, which could have caused the isolation of the Galera form distributed to the south of the Betic Corridor. Although lizards from the Albacete/Murcia and Galera lineage are morphologically similar, they clearly represent distinct genetic lineages. The noteworthy separation of the Galera lineage enables us to conclude that this lineage must be considered as a new full species.

×

Using video cameras and motion detection software, we examined sequential positions of the lizard Podarcis carbonelli in a temperature gradient to look for patterns in spatial and temporal thermoregulatory movements. As lizards shuttled between warm and cool areas, their movements were typically slow; punctuated by bursts of speed. The animals were relatively inactive when heating, moved almost continually when cooling, and spent less time heating than cooling. Traditional modeling techniques proved unsuccessful, so we assessed the movement patterns with nonlinear dynamical techniques. The shuttling frequency, and the pattern of velocity changes, both met the qualitative attributes (self similarity, strange attractors, and noisy power spectra) and the quantitative criteria (positive Lyapunov exponent and capacity and/or correlation dimensions less than 5) that suggest deterministic chaos. These movement patterns appear regular, but at unpredictable times the patterns become disturbed before returning to regulation. There are both behavioral and physiological advantages to movements that follow a model of deterministic chaos control.

×

The process of speciation is often equated to the acquisition of reproductive isolation. This is a process typically envisioned as being correlated to divergence time: as time progresses the more likely it will be for diverging taxa to experience restrictions to gene exchange. This correlation has been tested and verified in a wide range of taxa; however, other aspects of differentiation, such as ecological divergence, have also been shown to correlate with reproductive isolation independently of divergence time or genomic differentiation. Characterizing reproductive isolation in multiple pairs of closely related taxa that are in different stages of the divergence process is a way of addressing these questions and disentangling the factors are more importante as engines of reproductive isolation. Wall lizards of genus Podarcis, particularly those belonging to the Iberian and North African group, are an appropriate model for this type of evaluations since they comprise various differentiated species with that establish a variety of natural contact zones. In this study we sampled and characterized patterns of hybridization in 9 contact zones between different species pairs using RADseq data. We found a generally low proportion of hybrids and contact zones were strongly bimodal in all cases, but with measurable differences in levels of gene flow among contact zones. Using data available from previous studies on this complex and in a multivariate statistical framework, we compared the level of hybridisation in each contact zone with several predictor variables: nuclear and mitochondrial genetic divergence, distribution overlap, and morphological, ecological and physiological distances between species. Our results show that, despite the general trend in other taxa, the level of hybridization in Podarcis contact zones does not seem to be correlated to divergence time. We discuss how other mechanisms may have influenced this pattern.

×

Recent empirical studies have demonstrated that speciation with gene flow is more common than previously thought. From a conservation perspective, the potential negative effects of hybridization raise concerns on the genetic integrity of endangered species. However, introgressive hybridization has also been growingly recognized as a source of diversity and new advantageous alleles. Carbonell’s wall lizard (Podarcis carbonelli) is an endangered species whose distribution overlaps with four other congeneric species. Our goal here was to determine whether P. carbonelli is completely reproductively isolated from its congeners and to evaluate the relevance of hybridization and interspecific gene flow for developing a conservation plan. We used restriction site associated DNA (RAD) sequencing to discover SNPs in samples from four contact zones between P. carbonelli and four other species. Principal component analysis, multilocus genotype assignment and interspecific heterozygosity suggest incomplete reproductive isolation and ongoing gene flow between species. However, hybridization dynamics vary across all pairs, suggesting complex interactions between multiple intrinsic and extrinsic barriers. Despite seemingly ubiquitous interspecific gene flow, we found evidence of strong reproductive isolation across most contact zones. Instead, indirect effects of hybridization like waste of reproductive effort in small isolated populations may be more problematic. Our results highlight the need to further evaluate the consequences of introgression for P. carbonelli, both on a geographic and genomic level and included in a comprehensive and urgently needed conservation plan. Besides, those findings will add important insights on the potential effects of hybridization and introgression for endangered species.

×

Niche divergence among closely related lineages can be informative on the ecological and evolutionary processes involved in differentiation, particularly in the case of cryptic species complexes. Here we compared phylogenetic relationships and niche similarity between pairs of lineages included in the Podarcis hispanicus complex to examine patterns of niche divergence and its role in the organization of current diversity patterns, as allopatric, parapatric, and sympatric lineages occur in the Western Mediterranean Basin. First, we used ecological niche models to characterize the realized climatic niche of each Podarcis hispanicus complex lineage based on topographic and climatic variables, to identify important variables, and to test for niche conservatism or divergence between pairs of lineages. Variables related to precipitation generally exhibited the highest contribution to niche models, highlighting the importance of rainfall levels in shaping distributions of Podarcis wall lizards. We found that most forms have significant differences in realized climatic niches that do not follow the pattern of mitochondrial divergence. These results lend support to the hypothesis that genetic divergence across Podarcis hispanicus complex most likely occurred in allopatric conditions, mostly with significant niche divergence. Competition after secondary contact is also suggested by the common occurrence of niche overlap between lineages that exhibit strictly parapatric distribution. The almost continuous distribution of Podarcis lizards in the study area appears to be a result of a combination of complementary suitable niches and competition, which seem two important mechanisms limiting geographic distributions and restricting the existence of extensive contact zones.

×

A critical review of the evolutionary biology of Iberian and North African lizard members of the genus Podarcis (Lacertidae) based on phylogeny, phylogeography, morphometrics, behavior, ecology and physiology is presented. The Iberomaghrebian region is inhabited by at least 12 different evolutionary lineages that group into a monophyl- etic clade (except Podarcis muralis). In contrast to the current taxonomy, the saxicolous ‘Podarcis hispanica’ is paraphyletic with respect to Podarcis bocagei and Podarcis carbonelli, two currently recognized species. Nodes in the phylogenetic tree are deep, resulting from old divergences, clearly preceding the Pleistocene. Nevertheless, more recent range changes as a result of glaciations are also evident. The most plausible evolutionary scenario for this group indicates both vicariant and dispersal events. Although parapatry between lineages is the rule, sympatry and even syntopy are frequent, but usually between ground-dwelling and saxicolous forms. Contacts between forms with similar habitat use are rare and local. Morphological distinctiveness between lineages has been demonstrated, indicating historical constraints. However, other characters have repeatedly evolved under similar environmental pressures independently of the evolutionary lineage. Strong sexual dimorphism derives from sexual selection and is attained before sexual maturity, although developmental restrictions exist. Variation between popu- lations is also important and derives from local variation in both natural (habitat, climate) and sexual (density) selective pressures. Evidence for short-term changes has already been found, particularly in insular populations. Reproductive isolation between syntopic forms and partner recognition are based on male–male competition and on visual and chemical recognition of females by conspecific males. Despite this ancient diversification, most forms maintain a degree of reproductive compatibility. Hybridisation may occur, but is limited, and there is evidence of selection against hybrids. The ecological analysis presented here does not support exploitative competition, but rather behavioral interference between forms. Ecomorph classification of lineages suggests character displacement between those with extensive range overlap. Finally, a critical assessment of the specific status of all lineages is provided and directions for further research are suggested.

×

Lacertids are considered conservative in terms of their thermal physiology. Namely, whereas their temperatures in the field vary according to the environment, their preferred body temperatures (Tp) when free of thermal constraints remain similar within species even if under different climate regimes. In contrast, phylogenetically distant lacertid lineages sharing the same habitats may display distinct Tps more related with their biogeographic origins. The evolutionary limits of this so-called thermal rigidity remain, nevertheless, undefined. Here, the variation of Tp is analysed across the Iberomaghrebian Podarcis clade (P. bocagei, P. carbonelli, P. vaucheri and P. hispanica sensu lato). For this monophyletic group of closely related forms, some still not formally described, the knowledge of their phylogenetic relationships, divergence times and palaeoecological scenarios is now considerably robust. A total of 229 adult lizards belonging to 11 lineages were exposed to a thermal gradient and temperatures were recorded at 9 time intervals within the period of activity. Once the effects of diel rhythms, size and pregnancy were excluded, variation in Tp was recorded between some of the forms. Lineages diverging during the Pleistocene displayed similar Tps whereas sister taxa separated since the Pliocene show significant differences even if current ranges overlap. The most basal lineages in the phylogeny selected for different temperatures even if sister taxa but approached others not directly related to them. Apparently, divergence times higher than 3 mya are able to promote Tp shifts in this species complex. Such results are discussed in relation with the evolutionary history of this group.

×

Antipredator strategies in lacertids vary across and within species. Previous investigations have documented divergent strategies in both escape and recovery behaviour between syntopic species, between conspecific populations inhabiting different habitats and between colour morphs and size classes within the same population. Here, we evaluate the degree of plasticity in the different components of the antipredatory behaviour by comparing two conspecific populations under divergent disturbance regimes but otherwise environmentally similar. We examined the lizard responses under direct attack from a predator (simulated by the researcher) in two populations of Podarcis carbonelli from geographically close (1200 m) sites from Doñana National Park (SW Spain). In both cases, lizards mainly occupied wooden passes on sandy soil allowing park visitors to reach fauna observatories but, while one (El Acebuche) was heavily frequented (40,000-50,000 visitors/year) the other (Ribetehilos) was not (<500). Field experiments were carried out in both sites during days with suitable conditions within a period with optimal temperatures but out of the reproductive period (November 2010) to exclude factors other than site, sex and size class. We recorded variables describing lizard traits (sex, size class), environment (microhabitat, refuge) and behavioural responses for 128 observations (63 for El Acebuche and 65 for Ribetehilos) throughout random walking routes. Lizards from the most disturbed population (El Acebuche) were observed closer to their refuges than those from the less disturbed one (Ribetehilos), regardless their sex, size class and habitat features. While the first were also observed on hotter substrates and males in general escaped into hotter refuges, thermal environment was insufficient to explain the behavioural differences found. By contrast with previous studies comparing species or colour morphs, no variation between sites for either escape distance, recovery time or recovery distance was recovered despite the good samples sizes. Results reinforce previous claims that individual lizards may respond to different levels of disturbance in a directional way. However, they also indicate that some components of the antipredator behaviour are more plastic that others. This should be confirmed by further experimental work.

×

The spermatogenic cycles of Podarcis bocagei and P. carbonelli, two lacertids previously considered conspecific, were analysed in northwest Portugal. Monthly sampling was carried out at three sites: a zone of strict syntopy and two sites of allopatry for both species, all of them geographically close and harbouring similar habitats. The maritime Atlantic climate, which allows males to remain active most of the year, plays a determinant role on the variation of the mixed- type cycle, typical of lacertids in temperate regions. Comparison with other populations and species indicates that climate modifies the pattern of spermatogenesis by restricting the beginning (but not the end) of the activity period. Results also corroborate previous studies that report an agreement between the variations in the gonads observed at both microscopic and macroscopic scales in the reproductive period. Peaks for spermatozoa were delayed in sympatry but competition cannot be directly concluded. Furthermore, relationships between the number of spermatozoa and body size suggest sperm competition and possibly a reproductive interaction between the species.

×

A parasitological survey was carried out to determine the relationships between the helminth fauna and biological traits of the hosts in three Algerian populations of Podarcis lizards belonging to two different evolutionary lineages. Size, sex, and locality of collection, as well as the infracommunities and component communities, were analyzed. Very low values of parasite infection parameters and diversity were found in all three populations. This is in accordance with the feeding habits of these lizard hosts, which only eat animal prey and no plant matter. Spauligodon saxicolae (Nematoda: Pharyngodonidae), a specialist in lizards, is reported here for the first time in Africa. This nematode was the dominant parasite species for the three populations of lizards regardless their phylogenetic lineage, size, sex, and environmental conditions.

×

Ecological niche models (ENMs) will successfully identify a species` ecological niche, provided that important assumptions are fulfilled, namely environment equilibrium and niche equality across the distribution. Violations may seriously affect ENM reliability, leading to erroneous biogeographic conclusions and inappropriate conservation prioritisation. We evaluate the robustness of ENMs against incomplete knowledge of distribution with a real example, the threatened Iberian lizard Podarcis carbonelli, whose distribution was gradually discovered over a long time period. We used several ENM methods for presence-only data (Maxent, ENFA, Bioclim, and Domain) to infer the realised ecological niche at two spatial resolutions (1 km and 200 m). The distribution data were split into four partial datasets corresponding to separate subranges: Central System (CS); Viseu-Aveiro (VA); Atlantic coast (AC); and Doñana (DO). We then accumulated the datasets following the species discovery sequence: CS + VA, CS + VA + AC, and CS + VA + AC + DO. Niche equivalence and similarity between partial models were compared using Ecospat. ENMs were strongly affected by the violation of niche equilibrium; only the VA subrange forecasts the complete species range. ENMs were also sensitive to the violation of niche equality: only VA models were similar to the Iberian model, altitude being the most important variable followed by annual precipitation, maximum temperature in July, and annual radiation. When the ENMs were applied only to the first subrange discovered (CS), only the VA area was predicted, while the other subranges might have remained unknown, thus compromising conservation strategies. As assumptions of niche equilibrium and equality were violated, likely owing to the species` ecological multimodality, the models generated were biased and of limited predictive value. ENMs are useful tools in biogeography and conservation, but only if their basal assumptions are achieved. Partial models may be useful if they are considered as representing different suitable habitats.

×

Being excellent models in evolutionary ecology, lizard populations isolated by ecological reasons are also relevant for conservation because of their vulner- ability to extinction. Both aspects are linked because the ecological and evolu- tionary traits need to be known for developing conservation strategies. Here were report two cases, the lacertids Podarcis carbonelli and Lacerta schreiberi, in which a combined methodology is being applied. Both species, endemic to the Iberian Peninsula and with Atlantic affinities, display a continuous distribution in the northwest which becomes fragmented southwards. Southern isolates are fre- quently small, surrounded by unsuitable Mediterranean environments and more than 100 kilometres apart from their main ranges. Two isolates, P. carbonelli in Doñana and L. schreiberi in Montes de Toledo, are currently been monitored.

×

Background Lizards of the genus Podarcis are widespread in the Mediterranean region, including islands and island archipelagos. These small-bodied lizards have a predominantly protective green-brown colouration. However, some populations display unusual patterns, in which the colouration is predominantly blue or uniformly black. This study explores the factors that influence this chromatic variation, whether environmental (climate and island conditions) or evolutionary (phylogenetic trait conservatism). The colouration of 1400 individuals (27 species) was analysed in the CIELAB colour space. Results Pagel’s λ indicated that colouration is weakly conserved within phylogenetic lineages. Although the island surface plays a key role in the chromatic variability of these lacertids, geographic isolation and climate hold less influence. The colouration of some small island populations tends to be uniform and dark, possibly due to intense intraspecific competition and lower predatory pressure. Conclusions This study highlights the importance of island populations in understanding the processes that favour the emergence of extreme phenotypes in small ectothermic vertebrates.

×

There is an increasing recognition that fire is an important component of many ecosystems in the world, essential to understand the ecology and diversity of communities in fire-prone regions. It impacts fauna directly, through mortality, or indirectly by changing habitat structure and resources availability. In recent decades global warming, land abandonment and changes in traditional agricultural activities are driving changes in the frequency and extent of fires. In this context, to know the response of organisms to fire regimes is a conservation priority. Reptiles are a good model group to examine their responses to fire as they are ectothermic, sensible to modifications in habitat attributes such as vegetation structure and canopy closure, have low mobility and dispersal rates, and experience high rates of population declines and extinction. The purpose of this study is to evaluate the effects of fire on reptile assemblages at two geographic scales: at a worldwide scale, where I examined patterns of reptile responses to fire considering the time since fire effect with a meta-analysis methodology (Chapter 1); at a local scale, where I evaluated the effect of wildfires on the reptile communities of the Serra da Estrela Natural Park, namely on the population densities, species richness (Chapters 2) and examined how the trophic ecology and interspecific interactions varied with fire using the Psammodrome lizard as a model species (Chapter 3). For this, I used a set of proper methodologies in order to collect and analyze all the data needed to perform this study (search scientific data for a meta-analysis; transects for reptile surveys followed by vegetation and habitat structure characterization; fecal pellets analysis and network metrics for lizard‟s diet). At a worldwide scale, lizards‟ diversity (richness) but not abundance decreases immediately after fire (<1 year) but recovers quickly to pre-fire levels with increased abundance. Regarding snakes, diversity is not significantly affected by time-since-fire but abundance decreases in the latter stages of the post-fire succession. In Serra da Estrela Natural Park, reptile abundance decreases in the first 5 years of post-fire succession, but increases in the interval between 5-10 years. I also found that Psammodromus algirus is positively related with tree cover, and negatively related with herbaceous cover. Plant diversity is also a relevant parameter for reptiles, since its presence (abundance) is positively related with the diversity of plant species. Relatively to the diet, metrics of the bipartite network for lizards collected in unburned and burned habitats demonstrated that P. algirus presents more selective behaviors in unburned habitats, than in burned ones. I have also found differences between burned and unburned areas as regards availability of prey, being the burned area the one presenting the richest arthropod communities. My results suggest that immediately after fire there is a decrease in species richness but communities recover quickly and reptile abundance increases in early stages of post-fire succession (both globally, and also in Serra da Estrela Natural Park). Although reptiles present a close relation with habitat structure, they seem well adapted to areas with different time since fire and present stable abundances across the post-fire succession. Moreover, they have diet variation and are adapted to consume a large variety of preys when conditions are not suitable. In undisturbed areas, they may present a selective behavior.

×

Major histocompatibility complex (MHC) genes are crucial for the adaptive immune response of jawed vertebrates. Their variation, reaching extreme levels, is driven mainly by an arms race between hosts and pathogens. One hypothesised mechanism contributing to MHC polymorphism is adaptive introgression, the exchange of genetic variants between hybridising species favoured by selection, yet its effect on MHC variation is poorly understood. Detection of adaptive MHC introgression, though challenging, may be facilitated by the analysis of species complexes forming multiple hybrid zones. Here, we investigated MHC introgression in six hybrid zones formed by seven species of Podarcis lizards inhabiting the Iberian Peninsula. To differentiate adaptive introgression from neutral introgression, we compared the patterns of gene exchange in MHC and genome-wide markers. We found elevated sharing of MHC alleles in the proximity of contact beyond the areas of detectable genome-wide admixture in most hybrid zones and, in half of them, asymmetric MHC exchange. In general, the elevated MHC allele sharing between species pairs with abutting ranges compared to geographically isolated species pairs also supports the prevalence of introgression. Collectively, our results demonstrate widespread MHC introgression in the Iberian Podarcis complex and suggest its adaptiveness. Contrary to previous results from Triturus newts, we did not observe differences in the rate of introgression between MHC classes. Our work adds support to the emerging view of adaptive introgression as a key mechanism shaping MHC diversity. It also raises questions about the effect of elevated MHC variation and factors leading to the asymmetry of adaptive introgression.

×

A survey of gastrointestinal helminth communities of Podarcis bocagei and Podarcis carbonelli (Sauria: Lacertidae) from NW Portugal was conducted to determine the prevalence, intensity and diversity of intestinal parasites in these lizards. A few parasite species were found in both hosts, their prevalences, mean intensities and abundances of infection being low or very low. Low values of richness and abundance of parasite species were also found in the helminth infracommunities of individuals of both host species. These low values of parameters of infection and diversity are discussed and compared between both host species and among other Iberian lacertid lizards.

×

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.

×

Múltiples trabajos sobre comunicación química han revelado que el sistema químiosensorial influye numerosos procesos subyacentes a la ecología y evolución de los reptiles. Sin embargo, sabemos muy poco sobre cómo la señalización química se ve influida por factores ecológicos y evolutivos. Sobre esta base, hemos elegido los lagartos como modelo de estudio para investigar la comunicación química, utilizando diferentes enfoques (químico, comportamental o evolutivo). Así, hemos descrito una metodología analítica alternativa para el estudio de las secreciones químicas de lagartos basada en el uso de cromatografía de gases acoplada a espectrometría de masas (GC-MS). Además, hemos estudiado un caso de dimorfismo sexual en la señalización química del lagarto Liolaemus wiegmanni. También investigamos si restricciones en la dieta pueden obstaculizar la expresión de una señal potencialmente honesta (vitamina E) en Iberolacerta cyreni. Además, evaluamos divergencias en la señalización química entre especies relacionadas (Podarcis bocagei y Podarcis carbonelli) y entre poblaciones de la misma especie (Gallotia galloti), discutiendo si el ambiente podría ser el causante de tales diferencias. Finalmente, estudiamos la diversificación de las glándulas foliculares epidérmicas y algunos de los compuestos identificados en las secreciones glandulares a lo largo de Squamata y lacértidos, respectivamente. Así, hemos encontrado que la metodología analítica propuesta es capaz de detectar efectos fisiológicos y ambientales (temperatura) en la composición de las señales química de los lagartos. Por otro lado, las hembras de L. wiegmanni pueden transmitir información a través de las glándulas foliculares y además, esta información es significativamente distinta a la de los machos. Revelamos también que la suplementación en la dieta de vitamina E a los machos de I. cyreni alteró la señalización química y la respuesta inmune de los machos, así como la respuesta comportamental de las hembras. Además, encontramos considerables diferencias en las señales químicas de P. bocagei y P. carbonelli, lo que podría estar asociado a diferencias ambientales entre ambas especies. También, observamos divergencias en el perfil químico de las secreciones femorales de tres poblaciones de G. gallotia (G. g. eisentrauti, G. g. galloti and G. g. palmae), las cuales podrían estar provocadas por diferencias en las condiciones de temperatura y precipitación donde habita cada población. Además, observamos posibles efectos estacionales en los perfiles químicos de G. g. eisentrauti y G. g. galloti. Nuestros análisis sobre la evolución de los ocho compuestos revelaron una diversificación heterogénea de los mismos en cuanto a modo y tiempo. Respecto a las glándulas foliculares epidérmicas en Squamata, nuestros resultados sugieren que el número de estas sigue un modelo de evolución estabilizante, en el que habría un efecto moderado de la señal filogenética. Obtuvimos que la ausencia de estas glándulas sería el estado ancestral en Squamata con un considerable efecto de la filogenia en la localización anatómica de las mismas. El sexo, las condiciones climáticas, la dieta y las relaciones filogenéticas se revelan como factores influyentes en la composición final de las señales químicas de los lagartos y por tanto, el estudio desde múltiples perspectivas es la única vía para conseguir finalmente un profundo conocimiento del papel que juega el sistema quimiosensorial en la ecología y evolución de los lagartos.

×

Chemical signals play an important role in intraspecific communication and social organization of many animals, but they also may be useful in interspecific recognition. In lizards, chemical signals are often contained in femoral gland secretions, of which composition may vary between species and populations. This may be especially important in recognition and reproductive isolation between closely related species. We analyzed by gas chromatography-mass spectrometry (GCeMS) the lipophilic fraction of femoral gland secretions of two closely related wall lizard species, Podarcis bocagei and Podarcis carbonelli to test for possible interspecific differences in chemical composition. We found 56 lipophilic compounds in femoral gland secretions of male P. bocagei and 60 in P. carbonelli. The main compounds were steroids and waxy esters, but we also found carboxylic acids and their esters, alcohols, amydes, aldehydes, squalene, ketones and furanones. There were significant differences between species with respect to the number and relative proportions of compounds. Differences in chemical composition might be a consequence of phylogenetic differences per se, but they could also be explained by ecological adaptation to different microclimatic conditions. These differences in chemical profiles may explain the known chemosensory interspecific recognition between these two lizards, contributing to their reproductive isolation.

×

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).

×

Aim To examine the effect of a known geological barrier on genetic variation within a wall lizard species complex. Location The Iberian Peninsula and North Africa. Methods Sequencing of partial 12S rRNA and cytochrome b mtDNA. Results The current distribution of genetic variability is not related to the opening of the Strait of Gibraltar. Conclusions Podarcis hispanica in North Africa is probably a species complex. The Strait of Gibraltar should not be used as a known barrier to gene flow in other land based organisms without careful sampling to test for multiple crossings since its formation.

×

Wall lizards (Podarcis) are the dominant reptile group across most of southern Europe. Their taxonomy is complex because most species exhibit substantial intraspecific morphological polymorphisms. We have estimated the phylogeny of the particularly diverse western Iberian forms using partial cytochrome oxidase and cytochrome b mitochondrial DNA sequence data and have compared this against morphological variation. Of the two currently recognized species in the area-Podarcis hispanica and P. bocagei-neither is monophyletic, and extremely high genetic diversity between newly identified forms (up to 15% cytochrome b divergences) indicates that both are species complexes. Podarcis b. bocagei is genetically distinct from P. (b.) carbonelli which appears to be a separate species using both mtDNA and protein electrophoretic data. The insular form previously assigned to P. b. berlengensis, and sometimes argued to deserve species status is not genetically distinct from P. (b.) carbonelli using the mtDNA sequences. P. hispanica can be separated into at least four highly divergent groups, two in western Iberia, one in eastern Iberia and one in North Africa.

×

Phylogenetic relationships between species and morphotypes of Podarcis wall lizards from the Iberian Peninsula and north Africa were estimated using partial 12S rRNA and cytochrome b mitochondrial DNA sequences. All species except Podarcis hispanica form monophyletic units. P. hispanica is paraphyletic, although all identified morphotypes are monophyletic. These morphotypes represent highly divergent lineages showing 10–15% pairwise sequence divergence with the cytochrome b gene. The data suggest that P. hispanica is a species complex. We recommend using P. hispanica* until additional sampling delimits the number and ranges of species currently referred to P. hispanica. P. carbonelli, which has recently been raised to species status, is confirmed as a genetically distinct form. P. atrata is genetically distinct, but much more closely related to some populations of P. hispanica than previously thought.

×

1. Research addressing the effects of global warming on the distribution and persistence of species generally assumes that population variation in thermal tolerance is spatially constant or overridden by interspecific variation. Typically, this rationale is implicit in sourcing one critical thermal maximum (CTmax) population estimate per species to model spatiotemporal cross‐taxa variation in heat tolerance. Theory suggests that such an approach could result in biased or imprecise estimates and forecasts of impact from climate warming, but limited empirical evidence in support of those expectations exists. 2. We experimentally quantify the magnitude of intraspecific variation in CTmax among lizard populations, and the extent to which incorporating such variability can alter estimates of climate impact through a biophysical model. To do so, we measured CTmax from 59 populations of 15 Iberian lizard species (304 individuals). 3. The overall median CTmax across all individuals from all species was 42.8 °C and ranged from 40.5 to 48.3 °C, with species medians decreasing through xeric, climate‐generalist and mesic taxa. We found strong statistical support for intraspecific differentiation in CTmax by up to a median of 3 °C among populations. We show that annual restricted activity (operative temperature > CTmax) over the Iberian distribution of our study species differs by a median of > 80 hours per 25‐km2 grid cell based on different population‐level CTmax estimates. This discrepancy leads to predictions of spatial variation in annual restricted activity to change by more than 20 days for six of the study species. 4. Considering that during restriction periods, reptiles should be unable to feed and reproduce, current projections of climate‐change impacts on the fitness of ectotherm fauna could be under‐ or over‐estimated depending on which population is chosen to represent the physiological spectra of the species in question. Mapping heat tolerance over the full geographical ranges of single species is thus critical to address cross‐taxa patterns and drivers of heat tolerance in a biologically comprehensive way.

×

Podarcis bocagei and Podarcis carbonelli are two closely related species, endemic to the western Iberian Peninsula, whose biometric differences have already been established. However, their pholidosis has not been investigated in detail. We studied various pholidotic characters, often used for taxonomic purposes in the Lacertidae, in order to analyse scalation patterns in the two species and detect characters that could be useful for their diagnosis. The results show that both species present significant differences in various pholidotic characters, although patterns differ between the sexes. The combination of continuous and meristic characters allowed a good discrimination between P. bocagei and P. carbonelli, especially when sexes were separated a priori. However, the close phylogenetic relationship between the two species, along with their high intraspecific morphological variability, complicate the use of pholidotic characters as diagnostic tools in the field.

×

Podarcis bocagei and P. carbonelli are two closely related lacertid species, very similar morphologically and ecologically. We investigated sexual dimorphism patterns presented by both species in allopatry and in sympatry. Sexual size and shape dimorphism patterns were analyzed using both multivariate and geometric morphometric techniques. Multivariate morphometrics revealed a marked sexual dimorphism in both species--males being larger with more robust habitus and females presenting a longer trunk. General patterns of sexual size dimorphism are not modified in sympatry, although there is evidence for some morphological change in male head size. The application of geometric morphometrics offered a more detailed image of head shape and revealed that males present a more developed tympanic area than do females, while females have a more rounded head. Differences in the degree of sexual shape dimorphism were detected in sympatry, but no consistent patterns were observed. From the results of the study, and based on previous knowledge on the populations studied, we conclude that the morphological differences observed are probably not caused by exploitative competition between the species, but rather appear attributable to the modification of the relative influence of sexual and natural selection on both sexes.

×

Podarcis bocagei and Podarcis carbonelli are two lacertid species endemic to the western Iberian Peninsula, and both show head size and shape sexual dimorphism. We studied immature and adult head sexual dimorphism and analysed ontogenetic trajectories of head traits with body and head size, aiming to shed light on the proximate mechanisms involved. Immatures were much less dimorphic than adults, but geometric morphometric techniques revealed that head shape sexual differences are already present at this stage. Males and females differed in allometry of all head characters with body size, with males showing a disproportionate increase of head size and dimensions. On the other hand, head dimensions and head shape changed with increasing head size following similar trends in both sexes, possibly indicating developmental restrictions. Consequently, adult sexual dimor- phism for head characters in these species is the result of both shape differences in the immature stage and hypermetric growth of the head in relation to body size in males.

×

Podarcis bocagei and P. carbonelli are two closely related lizard species, endemic to the western Iberian Peninsula. Although genetic and morphological distinction between them is now well established, information on anatomical features is still very restricted. We studied presacral vertebrae number in both species, separately examining cervical and trunk vertebrae counts, in order to assess the interspecific and intersexual variation in these characters. There was no significant interspecific variation among lizards of the same sex for any of the vertebrae counts studied. However, important sexual variation existed, females presenting higher counts than males for both trunk and total presacral vertebrae, while males showed higher values of cervical vertebrae. Although our results lie within the known limits for other closely related species, they reveal that vertebrae number might present higher intraspecific variation than previously thought.

×

Sexual dimorphism in body size and shape in animals is normally linked to sexual selection mechanisms that modify the morphological properties of each sex. However, sexual dimorphism of ecologically relevant traits may be amplified by natural selection and result in the ecological segregation of both sexes. In the present study, we investigated patterns of sexual dimorphism of morphological traits relevant for locomotion in two lacertid lizards, Podarcis bocagei and Podarcis carbonelli, aiming to identify ontogenetic sources of variation. We analysed trunk and limb variation in relation to total body size, as well as the covariation of different traits, aiming to shed light on the proximate causation of adult sexual dimorphism. We find that, although immatures are generally monomorphic, adult females have a longer trunk, and adult males have longer fore and hind limbs. Both sexes differ substantially with respect to their growth trajectories and relationships between traits, whereas, in some cases, there are signs of morphological constraints delimiting the observed patterns. Because of the direct connection between limb size/shape and locomotor performance, which is relevant both for habitat use and escape from predators, the observed patterns of sexual dimorphism are expected to translate into ecological differences between both sexes.

×

Cryptic species complexes represent groups that have been classified as a single species, because of the difficulty in distinguishing its members morphologically. Morphological investigation following the discovery of cryptic diversity is crucial for describing and conserving biodiversity. Here we present a detailed account of morphological variation in a group of Iberian and North African Podarcis wall lizards of the family Lacertidae, trying to elucidate the morphological patterns observed between known mitochondrial lineages. Our results reveal very high morphological variation within lineages, considering both biometric and pholidotic traits, but also indicate that lineages are significantly different from each other. The main sources of variation, both globally and between lineages, arise from body size, head dimensions, and limb length, possibly pointing to underlying ecological mechanisms. A combination of body size, body shape, and continuous pholidotic traits allows a relatively good discrimination between groups, especially when comparing one group with the rest or pairs of groups. However, ranges of variation greatly overlap between groups, thereby not allowing the establishment of diagnostic traits. The high morphological variation observed indicates that external morphology is not particularly useful for species delimitation in this group of lizards, as local adaptation seems to play a major role in within- and between-group differentiation.

×

Podarcis carbonelli is a lacertid lizard endemic to the western Iberian Peninsula, with a highly fragmented distribution and complex patterns of phylogeographic structure. Here, we investigate intraspecific morphological variability in this species, considering both biometric and pholidotic traits. Our results reveal local patterns of variation in total body size and scalation, but also indicate the existence of gradual, geographically structured morphological variation when size-independent biometry is considered. Total body size is the main factor determining variation across our sample, but this seems to be the result of within-population variability in this trait and is not geographically structured. The southern isolated populations seem highly differentiated in morphological terms, a pattern that also corresponds to singular environmental conditions and distinctive genetic variation, and should therefore be the focus of special attention for future investigation and conservation.

×

Evolutionary inference based on molecular phylogenetic methods has profoundly modified the way that we understand biological diversity, unravelling a higher evolutionary diversity than previously considered. An exemplary case of this is the group of Iberian and North African Podarcis wall lizards. More investigated than any other reptile group in Europe, the Podarcis hispanica species complex comprises unexpectedly high levels of phylogenetic diversity and illustrates how the discovery of further cryptic diversity may entangle evolutionary inference. In the present study, we report on the discovery of two new mitochondrial lineages in this species complex, reassess the phylogeny of the group, infer the age of major phylogenetic splits, and provide a detailed description of the geographical distributions of all known mitochondrial DNA lineages. Our data show that the differentiation of major lineages is older than previously considered, in most cases predating the Messinian salinity crisis. The new lineages discovered and their position in the phylogeny of the group profoundly modify previous biogeographical scenarios, clearly showing that the area today corresponding to the south-eastern corner of the Iberian Peninsula is a very important centre of diversification. The dating obtained for the differentiation of the lineages currently inhabiting this area coincides with the complex geological events that took place during the Miocene/Pleistocene transition, supporting the idea that both land movements and dramatic climatic oscillations during that period could be involved. Finally, the discovery of these new lineages, together with the observed distribution patterns, not only further augments the uncertainty associated to our understanding of the evolutionary history of this group of lizards, but also points to new areas of interest for future investigation.

×

Among the Iberian members of the genus Podarcis, two species are present in the North-Western region: P. bocagei and P. carbonelli. The high morphological and ecological similarity between them as well as their well-known distribution ranges, provides a special opportunity to evaluate asymmetry patterns typically displayed by wall-lizards. Levels of asymmetry expression have been correlated with several kinds of abiotic, biotic and genetic stresses. The few asymmetry studies focusing on reptiles have found that even minor morphological asymmetries could have an impact on individuals’ survival, altering their fitness for example through reduced escaping performance. Others found that asymmetry varied across the species distribution range, increasing in the peripheral populations, while others evaluated isolation effects between insular and continental populations through fluctuating asymmetry. Therefore, asymmetry may be a useful fitness index but in order to be valuable in comparative studies, the levels of variation usually displayed by natural populations must be determined first. In our study we aim to define the asymmetry patterns present in these species through the analysis of meristic and linear biometric bilateral traits. We include characters from different structures, like the head and the limbs, to capture individual asymmetric variation. Measurement error was assessed in order to quantify the between sides variation truly due to asymmetry. After this initial stage, those traits that showed fluctuating asymmetry were analyzed separately because these can be used to evaluate the levels of developmental instability displayed by different populations. The occurrence of other types of asymmetry, particularly directional asymmetry, were also detected and evaluated. The similarity between asymmetry patterns of both species was tested as well as the occurrence of sexual dimorphism in asymmetry variation. We exemplify the application of asymmetry indices to a specific situation of sympatry, as it may pose stressful conditions to populations occupying similar habitats. The results will be presented in the ecological and evolutionary framework of these species.

×

Iberian Podarcis have been the target of intensive phylogenetic research during recent years because of the previously unexpected diversity found within. At present, the former Podarcis hispanica is recognized as a species complex parafiletic to P. bocagei, P. carbonelli and P. vaucheri with the majority of lineages being strongly supported by evidence coming from mtDNA, nuclear DNA and protein electrophoretic data. In some cases, morphological studies focusing on specific lineages have also agreed with their phenotypic distinctiveness which consequently conducted to their raise to the specific rank, such as P. carbonelli and P. vaucheri. However, some of the recent identified forms (i.e. “morphotype 1”) still contain considerable genetic diversity, while the apparent relationships of other monophyletic groups change according to the kind of data analyzed. From the recently published data, one highly divergent lineage seems to deserve a deeper look: Podarcis “morphotype 2”. This lineage is the most widespread in the Iberian Peninsula, reported from across the Central and Southwestern regions. While its distribution in Portugal is well defined, its eastern distribution is less well known. Reflecting this situation, recent studies lack representative samples from its entire distribution range. However, when mtDNA markers were preliminary analyzed, considerable variation was reported but without obvious geographic partitioning. With this study we aim to evaluate the genetic diversity within this form. We conducted a more complete sampling scheme trying to cover the entire distribution range of this specific lineage. We combine new and previously published sequence data in order to perform a more complete phylogeographic analysis of the whole lineage. Furthermore, the geographic distribution of this form is now more precisely delimited.

×

Podarcis bocagei y Podarcis carbonelli son dos especies cercanas de lacértidos endémicos del oeste de la Península Ibérica, cuyas diferencias biométricas ya han sido demostradas. Sin embargo, su folidosis nunca se ha estudiado detalladamente. Hemos estudiado diversos caracteres folidóticos, habitualmente utilizados en la taxonomía de lacértidos, con el objetivo de analizar los patrones que caracterizan ambas especies y detectar aquellos que podrían emplearse para su distinción. Los resultados demuestran que ambas especies presentan diferencias significativas en varios caracteres, aunque los patrones observados varían entre los sexos. La combinación de caracteres cuantitativos y cualitativos permitió una aceptable discriminación entre P. bocagei y P. carbonelli, especialmente cuando los sexos se separaron a priori. Sin embargo, las estrechas relaciones filogenéticas entre ambas especies y su elevada variabilidad morfológica intraespecífica dificultan la selección de caracteres que podrían servir como herramientas de diagnosis en el campo.

×

Identifying species is an important task in biology, medicine, pharmacology, agriculture and biodiversity conservation. Modern taxonomy, the discipline devoted to the description and identification of species, faces a decrease in its workforce while dealing with the challenge of describing the Earth’s vanishing biodiversity. In this context, automated identification of species becomes of major importance. Automated image identification is a thriving field of machine learning, with deep learning algorithms based on convolutional neural networks revolutionizing the field in recent years. These methods are also taking their first steps in the identification of images of biological taxa in a variety of different contexts and taxonomic scopes. In this work, we took a deep learning approach to classify images of Iberian and North African wall lizards, a group of cryptic species in which identification requires expert intervention. We addressed two problems: 1) a two-class problem focusing on the distinction between two species, Podarcis bocagei and Podarcis lusitanicus and 2) a nine-class problem involving all the species currently described in the group. Three different deep learning architectures were tested in both cases. In the two-class problem, classification success was high, reaching as high as 97.1% and 95.9% for ensemble models applied to male and female lizards, respectively. Classification in the nine-class problem was not as successful, highlighting the difficulties inherent to this group of cryptic species. However, results improved when predictions from different perspectives were combined, reaching 95.3% and 89.7% for males and females, respectively. These results suggest the utility of deep learning algorithms in the identification of cryptic species, providing promising resources in the taxonomical, evolutionary and conservation research.

×

A study in comparative morphology between two different populations of Podarcis carbonelli berlengensis on the Berlenga´s Archipelago was conducted and showed significantly differences between them. The lizards foun d on the island of Farilháo Grande are larger, have relatively longer limbs and are more melanistic than the indiciduals living on the island of Berlenga Grande. Differences related to the head shape, scalation and chromatic pattern were also found. Such differences could be assigned to different selective pressures, founder effect or genetic drift.

×

The results of two excursions (winter 1982/83 and spring 1983) to Portugal require the present additional note to my paper: `Contribution to the knowledge of the distribution of the Portuguese herpetofauna.` Remarkable new distributional data are provided for Chioglossa lusitanica, Alytes cisternasii, Pelobates cultripes, Tarentola mauritanica, Podarcis hispanica and Psammodromus hispanicus.

×

Within a 500 m margin along the more than 2,000 km long coastline of Continental Portugal, its coastal islands and atlantic archipelagos (Azores, Madeira, Selvagens) 21 amphibian and 40 reptile taxa (including 5 marine turtles) were recorded; three of them are insular endemisms (Tarentola bischoffi, Podarcis carbonelli berlengensis, and the polytypic Teira dugesii). The extreme maritim-atlantic component of the coastal climate plays a relevant part as biogeographic factor: parallel to the coast eurosiberian and montane species penetrate deep into the mediterranean region (Lissotriton helveticus, Alytes obstetricans, Anguis fragilis, Lacerta schreiberi, Podarcis carbonelli) and reach there the southernmost limit of their distribution area; on the other hand some thermophilous taxa (Pleurodeles waltl, Pelobates cultripes, Pelodytes sp., Podarcis hispanica) reach along the coast in the eurosiberian region their northernmost limit. In the last 30 years the coastal ecosystems were overrun by an excessive urbanisation, caused by inland immigration and tourism. Consequently in many coast sectors the herpetofauna are endangered, often extincted by urban and suburban development with fragmentation, degradation and destruction of habitats. Namely ca. 40 % of the coastal region are protected areas, but the effectiveness of this protection is threatened by many special permissions for building projects and an insufficient supervision of the nature reserves.

×

Portugal ist ein beliebtes Urlaubsland. Vor allem die Metropole Lissabon und die Atlantikstrände des Algarve ziehen Touristen an. Aber das Land an der Südwestspitze Europas hat noch viel mehr zu bieten. Die Serra de Montemuro ist ein lohnendes Reiseziel auch für alle, die nach Amphibien und Reptiulien Ausschau halten.

×

Gegenstand dieser Veröffentlichung ist die Darstellung der Verbreitungsverhältnisse der Amphibien und Reptilien der östlichen Beira Baixa (östliches Mittelportugal). Einleitend werden die geologischen und klimatischen Bedingungen beschrieben, das Habitatinventar und die den Raum betreffende herpetofaunistische Literatur vorgestellt. Im Untersuchungsgebiet wurden 16 Amphibien- und 23 Reptilienarten registriert, deren Verbreitung kartografisch auf der Basis eines 1 x 1 km UTM-Gitternetzes dargestellt wird. Während auf dem südlichen und zentralen Planalto mesomediterrane Arten vorherrschen, werden diese im nördlich gelegenen höheren Bergland durch supramediterrane und eurosibirische ersetzt. Pelodytes ibericus erreicht im Untersuchungsgebiet sein küstenfern nördlichstes, Hyla meridionalis den Grenzbereich seines landesweit nördlichsten Vorkommens. Triturus marmoratus und Triturus pygmaeus erscheinen in einer teilweise über 10 km breiten Überlappungszone in Sympatrie. Abschließend wird das Gefährdungspotenzial anthropogener Einflüsse (Ausbau der Infrastruktur, Einsatz von Agrochemie, Landnutzungswandel) auf die Herpetozönosen diskutiert und die Bedeutung der im Untersuchungsgebiet liegenden beiden großen Schutzzonen (Reserva da Serra da Malcata, Parque Natural Tejo Internacional) für die Herpetofauna erläutert.

×

We describe the distribution of the amphibians and reptiles of the Serra de Monte-muro (northern Portugal). In the introduction the geological and climatical condi-tions of this region as well as the habitat types and the herpetofaunistic studies are described. 11 amphibian and 17 reptile species were recorded. The distribution pat-tern of each species is shown by maps using the 1 x 1 km squares of the UTM grid system. In the montane region predominate north Iberian endemits (Chioglossa lusi-tanica, Rana iberica, Lacerta schreiberi; the occurrence of Podarcis bocagei is doubtful) and ubiquists (Salamandra salamandra, Triturus marmoratus, Lissotriton boscai, Pelophy-lax perezi; Chalcides striatus, Timon lepidus, Podarcis guadarramae). Along the rivers (Rio Douro, Rio Paiva), areas with components of Mediterranean climate, thermophile species (Chalcides bedriagai, Blanus cinereus, Hemorrhois hippocrepis) penetrate into the investigated area. Within the region Podarcis carbonelli reaches the northernmost oc-currence of its total distribution range. Remarkable is the high number of individuals of some montane Hyla molleri populations. Finally, the human impact on the land-scape (change of agricultural activities, reforestation in monocultures, widespread forest fires), its influence on the distribution pattern of the amphibians and reptiles and the efforts for protect the habitats are discussed.

×

Apart from analyses for elemental contaminants in field collected specimens, very little is known about the assimilation, accumulation and toxic effects of inorganic contaminants in reptiles. This study examined the chronic accumulation of Cd in a European lacertid lizard (Podarcis carbonelli) following dietary provision of an environmentally realistic concentration of Cd for 21 weeks. Lizards were provided with Cd that had either been biologically incorporated into crickets, or as Cd(NO3)2 added superficially to crickets just prior to feeding. Among both treatment groups Cd accumulated in tissues in the following order of concentration: gut > liver > kidney > carcass. The majority of the Cd was retained within the gut, and transfer to internal organs was low. Morphological indices, brain and plasma cholinesterase activities, gut and liver metallothionein content, and standard metabolic rate were measured as biomarkers of exposure and effect; however, no differences between control lizards and Cd-treated lizards were observed.

×

Apart from analyses for elemental contaminants in field-collected specimens, very little is known about the assimilation and accumulation of inorganic contaminants in reptiles. Recent dietary studies with reptiles (and some other vertebrates and invertebrates) have taken care to incorporate the principles of trophic transfer by pre-exposing prey items to the elemental contaminant of interest. However, there are conflicting data in the literature as to whether biologically incorporated metals are more bioavailable to consumers in a food chain than simple salts added to the diet, and this study examines this issue in a lacertid lizard. Adult individuals of Podarcis carbonelli were exposed to cadmium (Cd) in a 21-week dietary study to determine whether the form in which the Cd is provided influences assimilation efficiency for this metal. Lizards were provided with Cd that had either been biologically incorporated into crickets or as Cd(NO3)2 added superficially to crickets just prior to feeding. Radiospectrometric analysis for 109Cd in animal tissues and fecal material was used to follow Cd accumulation over the duration of exposure. The highest levels of accumulation were found within the gut. This, combined with the observation of higher rates of assimilation over the first five weeks, strongly suggests a rapid accumulation of Cd within the gut tissue followed by a slower redistribution to other tissues. No statistically different levels of Cd assimilation efficiency were detected between the two treatment groups, nor were there any statistically significant differences between the two treatment groups in relation to the proportional distribution to the gut, liver, or kidneys.

×

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.

×

Invasive species are a major threat to island biodiversity, and their eradications have substantially contributed to the conservation of island endemics. However, the consequences of eradications on the trophic ecology of native taxa are largely unexplored. Here, we used the eradication of invasive black rats Rattus rattus and European rabbits Oryctolagus cuniculus from the Berlenga Island, in the western coast of Portugal, as a whole-ecosystem experiment to investigate the effects of the eradication of invasive mammals on the trophic niche and body dimensions of the island-restricted Berlenga wall lizard Podarcis carbonelli berlengensis over a 2-year period. Our results suggest an expansion of the isotopic niche and an intensification of the sexual dimorphism of the lizard following mammal eradication. Additionally, we found considerable variability in isotopic niche across the island and detected evidence of sex-specific and season-modulated nutritional requirements of this threatened reptile. Our findings support that the eradication of 2 of the planet’s most problematic invasive vertebrates led to changes in the lizard trophic niche and sexual dimorphism in just 2 years. This suggests that the ecological pressures—for example, prey availability and habitat structure—to which lizards are exposed have substantially changed post-eradication. Our study emphasizes the scientific value of island eradications as experiments to address a wide range of ecological questions and adds to the increasing body of evidence supporting substantial conservation gains associated with these restoration interventions.

×

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.

×

The taconomic status of Podarcis bocagei in the Iberian Peninsula is reviewed. Since no Holotype is known, a Lectotype from the species is given. P. bocagei carbonelli ssp. n. is also described; it inhabits the western area of the Sistema Central, in particular the `Sierras` of Francia and Gata, both in Spain and the Serra da Estrela in Portugal. Finally, new localities for both subspecies are described, that together with those reported in the previous paper sum a total of 76 localities known up to date.

×

Iberian and North African Podarcis wall lizards constitute a cryptic species complex for which different morphological studies have produced largely conflicting results regarding the number, taxonomic rank and distribution of evolutionary entities. Recently, the assessment of mitochondrial DNA (mtDNA) diversity demonstrated the existence of highly differentiated and geographically consistent clusters, some of which corresponded neatly to partitions previously suggested by morphological analyses. As a result of this concordance, systematic reevaluations were carried out, and at present five different species are recognised: P. bocagei, P. carbonelli, P. vaucheri, P. hispanica and P. atrata, although the latter has been shown to be closely related to one of the various phylogroups that constitute the polytypic (and, from a mitochondrial DNA perspective, paraphyletic) P. hispanica. Given this framework, the first goal of this thesis was to characterize in more detail the dynamics of genetic differentiation among forms of this species complex. Previous descriptions of genetic variability within the complex relied on a single marker – mitochondrial DNA –, and biogeographical inferences were heavily dependent upon poorly supported estimates of relationships. On one hand, we aimed at obtaining a more robust mtDNA-based phylogenetic tree in order to validate previous hypotheses regarding the biogeographical processes governing variability within the clade. On the other hand, we sought to complement these data with information from the nuclear genome, in order to independently assess the distinctiveness of the various clades previously described. Additionally, by examining patterns of nuclear-mitochondrial concordance and analysing in detail the dynamics of a contact zone between two species, we were expecting to evaluate levels of reproductive isolation among forms of the species complex. The reevaluation of mitochondrial phylogenetic relationships was accomplished by selecting a few individuals from each lineage and extending the amount of included sequence data. In addition to the two mtDNA gene regions already published, we sequenced three other fragments, yielding a total of 2425bp. A robust phylogenetic tree was recovered, with a significant proportion of nodes receiving bootstrap support close to 100%. This rigorous assessment of mtDNA relationships between lineages confirmed some of the results obtained in previous studies, such as the paraphyly of P. hispanica. However, other aspects of the phylogeny differ, offering alternative scenarios for the timing and polarity of the colonization of North Africa by wall lizards. In particular, we suggest that the opening of the Strait of Gibraltar might have caused vicariant isolation of Iberian from North African forms, and that a subsequent transmarine colonization could have occurred from North Africa to Iberia. An additional important contribution of this study was the detection of a previously undescribed lineage inhabiting southern Spain, which further exemplifies the evolutionary complexity within this group. Two major lines of research were pursued regarding the description of nuclear gene variation: allozyme electrophoresis and sequencing of nuclear introns. The study of allozyme variation in 30 populations representing all known mtDNA lineages documented a high degree of genetic divergence between most of them, with groups within P. hispanica generally presenting similar levels of differentiation to those observed between fully recognised species. Although this constitutes evidence corroborating the validity of mtDNA lineages as evolutionary distinct units, the application of recent model-based clustering approaches revealed some important discordant patterns with respect to the mtDNA, which may be indicative of the occurrence of gene flow between forms. In this context, two hybrid individuals between the broadly sympatric P. bocagei and P. hispanica type 1 were detected. Summary viii Conversely, the study of two nuclear gene genealogies (β-fibint7 and 6-Pgdint7), demonstrated that, in general, species and mtDNA lineages are strikingly nonmonophyletic, which was unexpected given the high levels of differentiation detected by the use of other markers. An important issue that required clarification was, then, if this pattern emerged as the result of incomplete lineage sorting of ancestral polymorphism (motivated by the four-times higher effective population size of nuclear genes when compared to the mtDNA) or if it resulted from high levels of gene flow. In order to disentangle between these two non- mutually exclusive hypotheses, we estimated levels of gene flow between all pairs of lineages using recent methods of analyses based on coalescent theory that allow the study of the dynamics of admixture and divergence in the same framework. In contrast to the information obtained using classic, F-statistic-based estimators of gene flow, this approach revealed that only a few pairs of lineages have exchanged genes since their divergence, and even fewer show important levels of gene flow, suggesting that in general the various lineages are overall differentiated. Therefore, although gene flow has certainly played an important role in the evolution of the species complex (and as a result some mtDNA lineages may have even lost their nuclear identity), the polyphyletic pattern observed in nuclear genealogies is especially influenced by the persistence of ancestral polymorphism. These studies addressed the subject of gene flow among forms superficially, mostly based on the patterns of mitochondrial/nuclear discordance. In order to characterize in more detail the dynamics of gene flow, a battery of nuclear and mitochondrial markers was studied along a transect crossing the contact zone between P. bocagei and P. carbonelli. This information was complemented with analyses of morphology and fertility. Applying model-based individual multilocus genotype clustering approaches, we document abundance of individuals showing signs of admixture in the locality where the two species meet. However, strong Hardy-Weinberg and linkage disequilibria were observed. This clear bimodality suggests the existence of strong barriers to gene flow, the nature of which still remain obscure. For example, our data suggests neither obvious reductions in hybrid fertility nor the verification of Haldane’s rule. However, divergent natural selection acting on morphology is suggested by the fact that genetically admixed individuals are clearly assigned to one species or the other based on morphological characters. Bimodality within a hybrid zone is usually suggestive of a nearly complete process of speciation; while these results cannot be promptly generalized to other contact zones, they are in accordance with previous suggestions that, although Podarcis lineages are not fully reproductive isolated, levels of gene flow among them do not seem to challenge the ongoing process of differentiation. A second major goal of this thesis was to describe the phylogeographic structure within selected forms of the species complex using multiple molecular markers. In particular, we attempted to evaluate the response of the species to the Pleistocene climatic oscillations, comparing the patterns detected with phylogeographic scenarios described for other species occupying the same regions, and interpreting contrasting signatures left by the Ice Ages on distinct species of Podarcis. The study of mtDNA variation in P. bocagei, P. carbonelli and P. vaucheri, three species with parapatric distributions that replace each other along a latitudinal gradient, allowed us to test two predictions relative to the differential influence of Quaternary climatic oscillations on distinct latitudes: i) northerly distributed species are expected to bear lower levels of genetic subdivision and diversity than species distributed in the south because they were able to survive in fewer, smaller and less stable patches of favourable habitat during glaciations; ii) species distributed in the south should retain signs of long-term effective population size stability, while northern species, because they were more Summary ix confined during glacial stages, should have experienced a rapid demographic growth concomitant with a post-glacial colonization of newly available habitats. Our results show that P. bocagei presents remarkably low levels of diversity and subdivision, a shallow coalescent history (the estimated coalescence time was ~100,000-~70,000 years) and a strong signature of demographic growth. P. vaucheri, on the other hand, presents large levels of genetic diversity even at small geographic scales, strong geographic subdivision, no evidence of demographic growth and an ancient coalescence time, probably dating back to the initial stages of the Pleistocene. The intermediately distributed P. carbonelli presents average values of all studied variables. Taken together, these results entirely fit to our main predictions and demonstrate that different effects of the Ice Ages can be detected at small geographic scales. The analyses of nuclear markers (allozymes and a set of microsatellite loci specifically developed during this study) in populations of P. bocagei and P. carbonelli confirmed, on one hand, the low levels of population subdivision observed in both species from the study of mitochondrial DNA. Moreover, levels of differentiation are higher among populations of P. carbonelli than among populations of P. bocagei, which is also in accordance with higher levels of persistence and a consequent longer time for differentiation in the former inferred from mtDNA. In P. bocagei, we report a progressive loss of genetic diversity in a northwards fashion, consistent with a recent geographic expansion from a reduced source as suspected from mtDNA-based evidence of a rapid demographic growth. Moreover, based on a spatial interpolation of genetic data and on a Bayesian model-based multilocus genotype clustering algorithm, we were able to identify probable expansion routes and to pinpoint with some degree of certainty the area that has probably functioned as a glacial refugium for the species during the last glaciations. Applying the same methodology in P. carbonelli we document some degree of association between genetic clusters and geography, but with only partial correspondence to inferences based on mtDNA; to explain these discordant patterns, we hypothesise that recent fragmentations in the species’ distribution might have led to a loss of the genetic signatures that are typically found in co-distributed species, and that the patterns that are presently observed are more a byproduct of recent genetic drift than of Pleistocene climatic oscillations. Globally, these results constitute a major improvement regarding previous knowledge on evolutionary relationships, stages of differentiation, levels of gene flow and patterns of intraspecific subdivision in Iberian and North African Podarcis. At a more general level, the large-scale study of nuclear gene variation on these lizards, documenting polyphyly and gene flow among mtDNA lineages, illustrates that these correspond to very incipient species with permeable boundaries, highlighting the need for the assessment of multiple genetic markers prior to any taxonomic reevaluations. Moreover, the results have a double importance for the understanding of the Iberian and North African Quaternary biogeography: on one hand, by helping to confirm the transversality of patterns that appear in response to climatic fluctuations, such as glacial fragmentation and post-glacial expansion; on the other hand, by documenting how species-specific such patterns may be even among closely-related species.

×

Iberian and North African Podarcis wall lizards constitute a cryptic species complex for which different morphological studies have produced largely conflicting results regarding the number, taxonomic rank and distribution of evolutionary entities. Recently, the assessment of mitochondrial DNA (mtDNA) diversity demonstrated the existence of highly differentiated and geographically consistent clusters, some of which corresponded neatly to partitions previously suggested by morphological analyses. As a result of this concordance, systematic reevaluations were carried out, and at present five different species are recognised: P. bocagei, P. carbonelli, P. vaucheri, P. hispanica and P. atrata, although the latter has been shown to be closely related to one of the various phylogroups that constitute the polytypic (and, from a mitochondrial DNA perspective, paraphyletic) P. hispanica. Given this framework, the first goal of this thesis was to characterize in more detail the dynamics of genetic differentiation among forms of this species complex. Previous descriptions of genetic variability within the complex relied on a single marker – mitochondrial DNA –, and biogeographical inferences were heavily dependent upon poorly supported estimates of relationships. On one hand, we aimed at obtaining a more robust mtDNA-based phylogenetic tree in order to validate previous hypotheses regarding the biogeographical processes governing variability within the clade. On the other hand, we sought to complement these data with information from the nuclear genome, in order to independently assess the distinctiveness of the various clades previously described. Additionally, by examining patterns of nuclear-mitochondrial concordance and analysing in detail the dynamics of a contact zone between two species, we were expecting to evaluate levels of reproductive isolation among forms of the species complex. The reevaluation of mitochondrial phylogenetic relationships was accomplished by selecting a few individuals from each lineage and extending the amount of included sequence data. In addition to the two mtDNA gene regions already published, we sequenced three other fragments, yielding a total of 2425bp. A robust phylogenetic tree was recovered, with a significant proportion of nodes receiving bootstrap support close to 100%. This rigorous assessment of mtDNA relationships between lineages confirmed some of the results obtained in previous studies, such as the paraphyly of P. hispanica. However, other aspects of the phylogeny differ, offering alternative scenarios for the timing and polarity of the colonization of North Africa by wall lizards. In particular, we suggest that the opening of the Strait of Gibraltar might have caused vicariant isolation of Iberian from North African forms, and that a subsequent transmarine colonization could have occurred from North Africa to Iberia. An additional important contribution of this study was the detection of a previously undescribed lineage inhabiting southern Spain, which further exemplifies the evolutionary complexity within this group. Two major lines of research were pursued regarding the description of nuclear gene variation: allozyme electrophoresis and sequencing of nuclear introns. The study of allozyme variation in 30 populations representing all known mtDNA lineages documented a high degree of genetic divergence between most of them, with groups within P. hispanica generally presenting similar levels of differentiation to those observed between fully recognised species. Although this constitutes evidence corroborating the validity of mtDNA lineages as evolutionary distinct units, the application of recent model-based clustering approaches revealed some important discordant patterns with respect to the mtDNA, which may be indicative of the occurrence of gene flow between forms. In this context, two hybrid individuals between the broadly sympatric P. bocagei and P. hispanica type 1 were detected. Conversely, the study of two nuclear gene genealogies (β-fibint7 and 6-Pgdint7), demonstrated that, in general, species and mtDNA lineages are strikingly non- monophyletic, which was unexpected given the high levels of differentiation detected by the use of other markers. An important issue that required clarification was, then, if this pattern emerged as the result of incomplete lineage sorting of ancestral polymorphism (motivated by the four-times higher effective population size of nuclear genes when compared to the mtDNA) or if it resulted from high levels of gene flow. In order to disentangle between these two non- mutually exclusive hypotheses, we estimated levels of gene flow between all pairs of lineages using recent methods of analyses based on coalescent theory that allow the study of the dynamics of admixture and divergence in the same framework. In contrast to the information obtained using classic, F-statistic-based estimators of gene flow, this approach revealed that only a few pairs of lineages have exchanged genes since their divergence, and even fewer show important levels of gene flow, suggesting that in general the various lineages are overall differentiated. Therefore, although gene flow has certainly played an important role in the evolution of the species complex (and as a result some mtDNA lineages may have even lost their nuclear identity), the polyphyletic pattern observed in nuclear genealogies is especially influenced by the persistence of ancestral polymorphism. These studies addressed the subject of gene flow among forms superficially, mostly based on the patterns of mitochondrial/nuclear discordance. In order to characterize in more detail the dynamics of gene flow, a battery of nuclear and mitochondrial markers was studied along a transect crossing the contact zone between P. bocagei and P. carbonelli. This information was complemented with analyses of morphology and fertility. Applying model-based individual multilocus genotype clustering approaches, we document abundance of individuals showing signs of admixture in the locality where the two species meet. However, strong Hardy-Weinberg and linkage disequilibria were observed. This clear bimodality suggests the existence of strong barriers to gene flow, the nature of which still remain obscure. For example, our data suggests neither obvious reductions in hybrid fertility nor the verification of Haldane’s rule. However, divergent natural selection acting on morphology is suggested by the fact that genetically admixed individuals are clearly assigned to one species or the other based on morphological characters. Bimodality within a hybrid zone is usually suggestive of a nearly complete process of speciation; while these results cannot be promptly generalized to other contact zones, they are in accordance with previous suggestions that, although Podarcis lineages are not fully reproductive isolated, levels of gene flow among them do not seem to challenge the ongoing process of differentiation. A second major goal of this thesis was to describe the phylogeographic structure within selected forms of the species complex using multiple molecular markers. In particular, we attempted to evaluate the response of the species to the Pleistocene climatic oscillations, comparing the patterns detected with phylogeographic scenarios described for other species occupying the same regions, and interpreting contrasting signatures left by the Ice Ages on distinct species of Podarcis. The study of mtDNA variation in P. bocagei, P. carbonelli and P. vaucheri, three species with parapatric distributions that replace each other along a latitudinal gradient, allowed us to test two predictions relative to the differential influence of Quaternary climatic oscillations on distinct latitudes: i) northerly distributed species are expected to bear lower levels of genetic subdivision and diversity than species distributed in the south because they were able to survive in fewer, smaller and less stable patches of favourable habitat during glaciations; ii) species distributed in the south should retain signs of long-term effective population size stability, while northern species, because they were more confined during glacial stages, should have experienced a rapid demographic growth concomitant with a post-glacial colonization of newly available habitats. Our results show that P. bocagei presents remarkably low levels of diversity and subdivision, a shallow coalescent history (the estimated coalescence time was ~100,000-~70,000 years) and a strong signature of demographic growth. P. vaucheri, on the other hand, presents large levels of genetic diversity even at small geographic scales, strong geographic subdivision, no evidence of demographic growth and an ancient coalescence time, probably dating back to the initial stages of the Pleistocene. The intermediately distributed P. carbonelli presents average values of all studied variables. Taken together, these results entirely fit to our main predictions and demonstrate that different effects of the Ice Ages can be detected at small geographic scales. The analyses of nuclear markers (allozymes and a set of microsatellite loci specifically developed during this study) in populations of P. bocagei and P. carbonelli confirmed, on one hand, the low levels of population subdivision observed in both species from the study of mitochondrial DNA. Moreover, levels of differentiation are higher among populations of P. carbonelli than among populations of P. bocagei, which is also in accordance with higher levels of persistence and a consequent longer time for differentiation in the former inferred from mtDNA. In P. bocagei, we report a progressive loss of genetic diversity in a northwards fashion, consistent with a recent geographic expansion from a reduced source as suspected from mtDNA-based evidence of a rapid demographic growth. Moreover, based on a spatial interpolation of genetic data and on a Bayesian model-based multilocus genotype clustering algorithm, we were able to identify probable expansion routes and to pinpoint with some degree of certainty the area that has probably functioned as a glacial refugium for the species during the last glaciations. Applying the same methodology in P. carbonelli we document some degree of association between genetic clusters and geography, but with only partial correspondence to inferences based on mtDNA; to explain these discordant patterns, we hypothesise that recent fragmentations in the species’ distribution might have led to a loss of the genetic signatures that are typically found in co-distributed species, and that the patterns that are presently observed are more a by- product of recent genetic drift than of Pleistocene climatic oscillations. Globally, these results constitute a major improvement regarding previous knowledge on evolutionary relationships, stages of differentiation, levels of gene flow and patterns of intraspecific subdivision in Iberian and North African Podarcis. At a more general level, the large-scale study of nuclear gene variation on these lizards, documenting polyphyly and gene flow among mtDNA lineages, illustrates that these correspond to very incipient species with permeable boundaries, highlighting the need for the assessment of multiple genetic markers prior to any taxonomic reevaluations. Moreover, the results have a double importance for the understanding of the Iberian and North African Quaternary biogeography: on one hand, by helping to confirm the transversality of patterns that appear in response to climatic fluctuations, such as glacial fragmentation and post-glacial expansion; on the other hand, by documenting how species-specific such patterns may be even among closely-related species.

×

Podarcis bocagei and P. carbonelli are two Iberian-endemic wall lizard species for which a detailed phylogeographic study based on mitochondrial DNA (mtDNA) variation has been accomplished, showing that the two species responded differently to climatic oscillations during the Quaternary. In this study, our main goal was to assess whether nuclear markers reveal similar evolutionary patterns to those inferred from the study of mtDNA variation. We studied a battery of allozyme and microsatellite loci in populations from both species. For each species we evaluated overall levels of differentiation, the patterns of variation in genetic variability, genetic relationships among populations, changes in allele frequencies across the species’ distribution area and applied model-based individual multilocus genotype clustering approaches to detect hidden population structure. Our results for Podarcis bocagei are highly concordant with the phylogeographic scenario inferred from mtDNA variation: not only we find very low levels of population differentiation, consistent with survival in a single glacial refugium, but we detect signatures of a rapid demographic and geographic expansion, as suggested from mtDNA analyses. The analyses of nuclear markers furthermore helped in the identification of the probable refugial area, as well of expansion routes. Also with similarity to observations based on mtDNA variation, a low level of population differentiation was observed in P. carbonelli. In concordance with mitochondrial DNA, differentiation levels were slightly higher in P. carbonelli than those observed in P. bocagei. However, the geographic basis for differentiation in P. carbonelli is highly inconsistent between mtDNA and nuclear markers, suggesting a complex, albeit recent, history of isolation. Furthermore, a recent reduction on the species distribution has probably erased the signatures of glacial isolation and postglacial expansion that are normally found in other Iberian species, suggesting that the currently observed pattern of genetic differentiation in this species was shaped more by recent genetic drift than by the Pleistocene climatic oscillations.

×

The taxonomy of Iberian and North African wall lizards (Podarcis sp.) has been controversial. Recently, morphological and mtDNA sequence data have provided new information on differentiation within these lacertids. To compare these results to those provided by nuclear markers, we investigated variation at 11 polymorphic protein loci using conventional electrophoresis and isoelectric focusing in 11 populations belonging to seven different mtDNA lineages. A total of 62 alleles were found. Populations belonging to the same mtDNA type presented high genetic similarity, whereas strong differentiation was observed between groups. These results are consistent with those previously obtained from morphological and mtDNA analysis and support the idea that Iberian and North African Podarcis are composed of several well-differentiated entities, some of which are already recognized as species, whereas others (belonging to the P. hispanica complex) clearly need taxonomic revision.

×

Pleistocene climatic oscillations were a major force shaping genetic variability in many taxa. We analyse the relative effects of the ice ages across a latitudinal gradient in the Western Mediterranean region, testing two main predictions: (i) species with historical distributions in northern latitudes should have experienced greater loss of suitable habitat, resulting in higher extinction of historical lineages than species distributed in southern latitudes, where the effects of the ice ages were not as drastic. This would be reflected in the observation of lower diversity and number of differentiated lineages in northern areas. (ii) a signature of demographic expansion following the climate amelioration should be obvious in northern species, whereas in the south evidence of long-term effective population size stability should be observed. We used as models three species of wall lizards (Podarcis bocagei, Podarcis carbonelli and Podarcis vaucheri) that replace each other along the study area. We investigated the patterns of mitochondrial DNA diversity and subdivision and obtained demographic parameter estimates for each species. Our results suggest that P. bocagei, the northernmost species, bears low genetic diversity, a shallow coalescent history and marks of a demographic expansion. In contrast, P. vaucheri, the species with a southernmost distribution, shows deeper coalescence events, complex geographical substructure and no evidence for population growth. The species with an intermediate distribution, P. carbonelli, shows average levels of diversity, substructure and population growth. Taken together, these results conform to our main predictions and are explained by a differential influence of the ice ages on distinct latitudes.

×

Combining different sources of information is essential for a complete understanding of the process of genetic dif- ferentiation between species. The Iberian and North African wall lizard ( Podarcis ) species complex has been the object of several studies regarding morphological and mitochondrial DNA variation but, so far, no large-scale survey of nuclear variation within this group has been accomplished. In this study, ten polymorphic allozyme loci were stud- ied in 569 individuals collected across the Iberian Peninsula and North Africa. The obtained data were analysed using both conventional population genetic tools and recent Bayesian model-based clustering methods. Our results show that there are several well-differentiated entities corroborating the major splits observed in mtDNA analyses. These groups correspond not only to the fully recognized species Podarcis bocagei , Podarcis carbonelli , and Podarcis vaucheri but also to multiple forms within the polytypic Podarcis hispanica , all of which have a similar level of dif- ferentiation to that observed between the acknowledged species. However, relationships between forms are weakly supported both by population and individual clustering methods, suggesting a scenario of a rapid diversification that contrasts to the clear bifurcating model assumed from previous mtDNA analyses. Individual multilocus analyses report few individuals misassigned or apparently admixed, some of which are most likely explained by the persis- tence of high levels of ancestral polymorphism. Other admixed individuals, however, are probably the result of lim- ited levels of gene flow between forms.

×

Background: The study of recently-diverged species offers significant challenges both in the definition of evolutionary entities and in the estimation of gene flow among them. Iberian and North African wall lizards (Podarcis) constitute a cryptic species complex for which previous assessments of mitochondrial DNA (mtDNA) and allozyme variation are concordant in describing the existence of several highly differentiated evolutionary units. However, these studies report important differences suggesting the occurrence of gene flow among forms. Here we study sequence variation in two nuclear introns, β-fibint7 and 6-Pgdint7, to further investigate overall evolutionary dynamics and test hypotheses related to species delimitation within this complex. Results: Both nuclear gene genealogies fail to define species as monophyletic. To discriminate between the effects of incomplete lineage sorting and gene flow in setting this pattern, we estimated migration rates among species using both FST-based estimators of gene flow, which assume migration-drift equilibrium, and a coalescent approach based on a model of divergence with gene flow. Equilibrium estimates of gene flow suggest widespread introgression between species, but coalescent estimates describe virtually zero admixture between most (but not all) species pairs. This suggests that although gene flow among forms may have occurred the main cause for species polyphyly is incomplete lineage sorting, implying that most forms have been isolated since their divergence. This observation is therefore in accordance with previous reports of strong differentiation based on mtDNA and allozyme data. Conclusion: These results corroborate most forms of Iberian and North African Podarcis as differentiated, although incipient, species, supporting a gradual view of speciation, according to which species may persist as distinct despite some permeability to genetic exchange and without having clearly definable genetic boundaries. Additionally, this study constitutes a warning against the misuse of equilibrium estimates of migration among recently-diverged groups.

×

When recently diverged taxa come into contact, the extent of introgression between them is related to the degree of differentiation that they have achieved. Studying contact zones is therefore essential to understand if differentiated taxa are reproductively isolated and, ultimately, if they are likely to remain distinct. Recent work on Iberian and North African wall lizards (Podarcis) has documented the existence of multiple evolutionary units, diagnosable both by genetic markers and morphology, but suggests that gene flow between distinct forms has occurred. Therefore, we were interested in evaluating how species boundaries are maintained in the areas where they meet. In this work, we study the contact zone between Podarcis bocagei and Podarcis carbonelli. We sampled a transect including the only locality where these two lizards are known to occur in syntopy and analysed a battery of 15 unlinked nuclear genetic markers and mitochondrial DNA. We also conducted a preliminary analysis of morphology and fertility. Using model-based clustering approaches, we show that the two species hybridize in the population where they have direct contact, but evidences of introgression are low for nearby populations. Although a significant number of individuals show evidence of admixture, this hybrid zone is clearly bimodal, suggesting strong barriers to gene flow, of which the putative nature are discussed. Interestingly, morphological analyses do not support the existence of intermediate forms among individuals that are admixed genetically. Taken together, these results constitute further evidence validating P. bocagei and P. carbonelli as distinct species.

×

When recently diverged taxa come into contact, the extent of introgression between them is directly related to the stage of differentiation that they have achieved. The study of contact zones is therefore essential to understand if differentiated taxa are reproductively isolated and, ultimately, to assess if they are likely to remain distinct. Recent work on differentiation within Iberian and North African wall lizards (Podarcis) has shown that multiple evolutionary units exist, diagnosable both by genetic markers and morphology, some of which have been recognised as full species. These studies also suggest that gene flow between distinct forms may occur. Therefore, we were interested in evaluating how species boundaries are maintained in the areas where they meet. In this work, we present data relative to the contact zone between P. bocagei and P. carbonelli. We studied a transect including the only known locality where these two lizards are known to occur in syntopy and analysed a battery of 15 unlinked nuclear genetic markers (11 allozymes, three microsatellites and one nuclear intron), mitochondrial DNA and morphology. We also conducted a preliminary analysis of fertility. Using model-based clustering approaches we show that the two species hybridize in the population where they contact, but evidences of introgression are low for nearby populations. Although a significant number of individuals show evidence of admixture, this hybrid zone is clearly bimodal, suggesting strong barriers to gene flow, which putative nature are discussed. Interestingly, morphological analyses revealed a complete lack of intermediate forms, even among individuals that are admixed genetically. Taken together, these results constitute further evidence validating the species status of P. bocagei and P. carbonelli.

×

Automated image classification is a thriving field of machine learning, and various successful applications dealing with biological images have recently emerged. In this work, we address the ability of these methods to identify species that are difficult to tell apart by humans due to their morphological similarity. We focus on distinguishing species of wall lizards, namely those belonging to the Podarcis hispanicus species complex, which constitutes a well-known example of cryptic morphological variation. We address two classification experiments: (1) assignment of images of the morphologically relatively distinct P. bocagei and P. lusitanicus; and (2) distinction between the overall more cryptic nine taxa that compose this complex. We used four datasets (two image perspectives and individuals of the two sexes) and three deep-learning models to address each problem. Our results suggest a high ability of the models to identify the correct species, especially when combining predictions from different perspectives and models (accuracy of 95.9% and 97.1% for females and males, respectively, in the two-class case; and of 91.2% to 93.5% for females and males, respectively, in the nine-class case). Overall, these results establish deep-learning models as an important tool for field identification and monitoring of cryptic species complexes, alleviating the burden of expert or genetic identification.

×

Podarcis bocagei and Podarcis carbonelli are two species of wall lizards endemic to the western Iberian Peninsula. A detailed phylogeographical study based on mitochondrial DNA (mtDNA) variation has shown that they responded differently to the Quaternary climatic oscillations. These differences have been attributed to their distribution patterns: P. bocagei is distributed in the north of the Peninsula and in a continuous fashion, whereas P. carbonelli has a more southern and fragmented distribution. In this study, we assessed whether nuclear markers reveal similar evolutionary patterns to those inferred from mtDNA variation. We studied a battery of allozyme and microsatellite loci in a geographically representative set of individuals from both species. For each species we evaluated overall levels of differentiation, patterns of geographical variation in genetic diversity, genetic relationships amongst localities, and applied model-based individual multilocus genotype clustering approaches to detect hidden population structure. Our results for P. bocagei are highly concordant with the phylogeographical scenario inferred from mtDNA variation: we found very low levels of population differentiation, consistent with survival in a single glacial refugium, and detected signatures of a rapid demographic and geographical expansion. The analyses of nuclear markers furthermore helped to identify a probable refugial area, as well as expansion routes. Additionally, in concordance with observations based on mtDNA variation, a low level of population differentiation was observed in P. carbonelli, but this was significantly higher than in P. bocagei. However, the geographical basis for differentiation in P. carbonelli is highly inconsistent between mtDNA and nuclear markers, suggesting a complex, albeit recent, history of fragmentation. A recent reduction of this species’ distribution has probably erased the signatures of glacial isolation and post-glacial expansion that are normally found in other Iberian species, suggesting that the currently observed pattern of genetic differentiation in this species was shaped more by recent genetic drift than by the Pleistocene climatic oscillations.

×

We report new primers for the amplification and sequencing of 11 nuclear markers in squamate reptiles and anuran amphibians (five in squamates, six in anurans). Ten out of the 11 loci are introns (three of which are linked) that were amplified using an exon-primed, intron-crossing (EPIC) PCR strategy, whereas an eleventh locus spans part of a protein-coding gene. Squamate and anuran primers were initially developed for Lacerta schreiberi (Squamata: Lacertidae) and Pelodytes spp. (Anura: Pelodytidae), respectively. Cross-species amplification of the squamate markers was evaluated in four genera representing two additional families, whereas for anurans three genera corresponding to three additional families were tested. Three out of the five loci were successfully sequenced in all squamate taxa tested. Cross-amplification of the six anuran markers had lower, but still significant, success. We predict these markers will be of great utility for both population genetics and phylogenetic studies.

×

Mitochondrial markers are still often used alone to identify evolutionary units, despite widespread evidence for processes such as incomplete lineage sorting or introgressive hybridization that may blur past population history. The combination of mitochondrial DNA data with other sources of information (morphology, nuclear genes) is a powerful tool to reveal when and why mitochondrial markers are potentially misleading. In this study, we evaluate the performance of mtDNA markers to unravel the evolutionary history of Spanish lizards from the Podarcis hispanicus species complex. We first uncover several cases of discordance between morphological and mitochondrial data in delimitation of taxa. To assess the origin of these discordances, we analysed the same populations using several independent nuclear loci. Both morphological and nuclear markers identified the same three evolutionary units in the region, while mitochondrial data revealed four deeply divergent lineages. We suggest here that the most likely scenario to explain this discordance is ancient mitochondrial introgression originating from a fourth evolutionary unit presently absent from the study area. Notably, this resulted in a complete replacement of the original lineage in a large part of the distribution of one of the taxa investigated. We discuss the potential evolutionary scenarios leading to this complete mitochondrial replacement and suggest why the previous studies have failed to recover the correct history of this species complex.

×

Host parasite specificity is related to several factors including the type of life cycle of the parasite, the habitat occupied by both parasites and hosts, and the food habits of the hosts. In this work, gastrointestinal helminths in two congeneric lacertid lizards, Podarcis bocagei and Podarcis carbonelli living in sintopy, have been analysed. Out of four helminth species found, three of them, the trematode Brachylaima sp., the cestode Oochoristica gallica and the nematode Skrjabinelazia hoffmanni, have indirect life cycles while the nematode Spauligodon carbonelli has a direct life cycle. Heteroxenous helminths showed low host specificity whereas S. carbonelli may be placed at an intermediate position in a continuum of the degree of specificity.

×

A parasitological survey was carried out to determine the relationships between helminth fauna and some biological traits of two host species of lacertid lizards. Size, sex, diet, and season of collection, as well as infracommunities and component communities of Podarcis bocagei and P. carbonelli from Douro litoral (northwest Portugal), have been analysed. In both host species, we found low values of parasite infection parameters and diversity. These findings were in accordance with their feeding habits, eating only animal prey and no plant matter. Evidences suggest a relationship between the presence of Brachylaima sp (Trematoda: Brachylaimidae) and the ingestion of snails by both lizard species. Spauligodon carbonelli (Nematoda, Pharyngodonidae), a specialist in Podarcis hosts, was the most important parasite, affecting mainly adult males with a prevalence of infection showing seasonal variation.

×

The presence of Haemogregarines (sensu lato) in the blood of many species of reptiles is not at all unusual. In Iberian and Canarian lacertid lizards, Haemogregarines have been recorded infecting erythrocytes. Most of the records were the mature gametocytes, and this fact always has disabled the accurate identification of these infecting forms because their morphology do not give enough information to identify them even at generic level. We have analyzed blood smears from 75 specimens of Podacis bocagei (Seoane, 1884) and 33 specimens of Podarcis carbonelli (Pérez- Mellado, 1981) from several localities of North-East Portugal. We found Haemogregarines (sensu lato) for 74.7% of P. bocagei and 69.7% of P. carbonelli. In order to progress in the identification of these Haemogregarines, we studied some characteristics other than the morphology of the mature gametocytes. Thus, we observed immature gametocytes (considered merozoytes by some authors) oval in form, and with a big central nucleus. Furthermore, we analyzed histologically the liver of 4 of the searched hosts (2 P. bocagei, 2 P. carbonelli). We detected the presence of latent cysts with sporozoytes. Both characteristics, the presence of merozoytes in the blood and the presence of cysts in the liver, have been recorded by several authors as typical of the genus Hepatozoon. Although more histological analysis are necessary to assert that the hole of the sample is infected by Hepatozoon, we suspect that not only P. bocagei and P. carbonelli from Portugal, but many species of Iberian (and probably Balearic and Canary) lacertid lizards (on which we are now developing some investigations) could be infected by species of this genus.

×

In Iberian and Canarian lizards, haemogregarines have been recorded infecting erythrocytes, but most of the records correspond to mature gametocytes. We analysed blood smears from 75 specimens of Podarcis bocagei (Seoane) and 33 specimens of P. carbonelli (Pérez-Mellado) from localities of north-western Portugal. We found haemogregarines in 74.7% of P. bocagei and 69.7% of P. carbonelli. Our observations show characteristics of the haemogregarines other than the morphology of the mature gametocytes. In histological sections of the liver of four hosts latent cysts with sporozoites and meronts with merozoites were detected. Both traits have been described as typical of the genera Hepatozoon Miller, 1908 and Hemolivia Petit, Landau, Baccam & Lainson, 1990. We suggest that not only P. bocagei and P. carbonelli from Portugal but other species of Iberian and Canarian lacertids might also be infected by species belonging to one or both genera.

×

There is growing concern that anthropogenic climate change may particularly affect ectotherm groups such as amphibians and reptiles. Effects of anthropogenic climate change were already observed on different levels, ranging from changes in the phenology of individuals to changes in entire populations, their demography and geographic ranges with losses and range gains. Especially the latter is exacerbated by interactions of climate change with existing risk factors such as the spread of patho- gens and invasive species. In extreme cases, species are threatened by extinction, which is most likely in endemic species occupying restricted ranges. In this review, possible future climate change scenarios as well as previous observations and general expectations of climate change induced changes in phenology, demography and bio- geography of amphibian and reptile species are presented. Individual case studies on climate change induced changes in demography of the common lizard as well as possible range shifts in the alpine newt are highlighted, with applied methods being discussed regarding different elements of uncertainty.

×

Environmental factors determining the presence of the Carbonell lizard Podarcis carbonelli (Pérez–Mellado, 1981) in the Doñana area.— The Carbonell lizard (Podarcis carbonelli) is an Iberian endemism. The region of Doñana is its southernmost and more isolated stronghold. We used logistic regressions to investigate the factors conditioning the presence of this lizard in Doñana. All selected models retained the distance to the coast as the main variable. This variable is related with less humidity and more continental climatic conditions, including more extreme temperatures, when further from the coast. This climatic factor was observed both spatially and temporarily, with adult lizards drastically reducing their activity both in winter and in summer. We observed juveniles from June to January, with a maximum in September. Scrubland management was another important environmental factor affecting the presence of lizards. The probability of finding this species was higher where the scrubland was partially cleared, and lower in areas with a high plant cover (hygrophytic scrubland) or in areas with sparse vegetation (dune scrubland), probably due to a lower amount of incident light and less protection when moving between refuges, respectively.

×

Environmental factors determining the presence of the Carboneli lizard Podarcis carbonelli (Perez-Mellado, 1981) in the Donana area.-- The Carbonell lizard (Podarcis carbonelli) is an Iberian endemism. The region of Donana is its southernmost and more isolated stronghold. We used logistic regressions to investigate the factors conditioning the presence of this lizard in Donana. All selected models retained the distance to the coast as the main variable. This variable is related with less humidity and more continental climatic conditions, including more extreme temperatures, when further from the coast. This climatic factor was observed both spatially and temporarily, with adult lizards drastically reducing their activity both in winter and in summer. We observed juveniles from June to January, with a maximum in September. Scrubland management was another important environmental factor affecting the presence of lizards. The probability of finding this species was higher where the scrubland was partially cleared, and lower in areas with a high plant cover (hygrophytic scrubland) or in areas with sparse vegetation (dune scrubland), probably due to a lower amount of incident light and less protection when moving between refuges, respectively.

×

The author reports on new locality records of the montane subspecies of Bocage`s Wall Lizard, Podarcis bocagei carbonelli PÉREZ-MELLADO, 1981 from Portugal, where the lizard was found in some highland areas (Montemuro, Leomil and Lapa mountains) situated north of its known range in the Estrela mountains. In the new places, the lizards were found in deforested areas colonized by broom and heather that had replaced the Pyrenean oak (Quercus pyrenaica).

×

The geographic distributions of the Bocage’s wall lizard, Podarcis bocagei and the Carbonell’s wall lizard, P. carbonellaein Portugal were determined through extensive field surveys. The river Douro constitutes the main geographical barrier where both lizard species show nearby a zone of contact. Predictive models of probability of occurrence were developed for both species in Portugal, based on the Logistic Multiple Regres- sion (LMR) and the Overlap Analysis (OA). On a coarse scale, the best-fit model suggested that the distribution of P. bocagei in Portugal might be largely explained by macroenvironmental variables such as radiation, eva- potranspiration or type of climate. The balance between the number of frost days per year and a coefficient of aridity (Kdr = 100 × temperature/precipitation) seems important to explain the range of P. carbonellae. Howe- ver, the large overlap found between predictive areas strongly suggest that historical events (e.g. Pliocene spe- ciation, Pleistocene glacial refugia) might have been preponderant, acting the macroenvironmental factors as ultimate determinants of the present-day distribution of both species. The distribution of P. bocagei is signi- ficantly congruent with that of Chioglossa lusitanica, partially with Vipera seoaneiand with Rana ibericaand Lacerta schreiberinorthwards the river Douro. Conversely, the contractive distribution ofP. carbonellaedid not share any significant pattern of congruence with the latter taxa.

×

Six biometric characters and 15 electrophoretic loci of three known subspecies of Podarcis bocagei were studied. Contrary to biometric indications, Podarcis bocagei berlengensis showed a closer genetic relationship with Podarcis bocagei carbonelli than with the nominal subspecies. The biometric results were confounded by the relative large size of P. b. berlengensis. Post-glacial colonization from two different areas might explain the greater genetic differentiation between the P. b. bocagei and P. b. carbonelli populations (Nei`s D - 0.158 - near the species threshold). It might also explain the known colonization of these two lizards through the islands off the west coast of the Iberian penninsula and their present distributions to the north of (Galicia; Northern Portugal) and to the south of the valley of river Douro (central Portugal, western and Sistema Central), respectively.

×

Podarcis carbonelli is considered a full species on the basis of its morphological and genetic divergence from P. bocagei and P. hispanica. Podarcis carbonelli differs from P. bocagei in all twelve biometric variables compared and also in chromatic patterns. Podarcis carbonelli diverges from P.bocagei by more than 13% between cytochrome b sequences (mitochondrial DNA), a value typically reported between congeneric reptile species. Biogeographical criteria also support this hypothesis, as both lizard forms have different distribution ranges with a limited parapatric zone of contact without morphological intermediates.

×

Climate change is negatively affecting many species. The increase in mean air temperature is often associated with shifts in distribution, changes in phenology, and local extinctions. Other factors that only partially correlate with air temperature, like water shortage, may also contribute to the negative consequences of climate change. Although the effect of temperature on lizards’ ecophysiology is highly studied, many lizards are also at risks of increased water loss and dehydration, which are predicted to increase under climate change. Here we aimed for the first time to explore if lacertid lizards exposed to dehydration thermoregulate less precisely than hydrated lizards and if dehydrated lizards are less active, change the daily pattern of thermoregulation and balance water balance against thermoregulation. We exposed four lizard species with differences in the thermal preference to thermal gradients with or without a source of water. We measured preferred body temperatures, daily pattern of thermoregulation, and the use of space. Dehydration negatively affected thermoregulation in all investigated species. Dehydrated lizards reduced their preferred body temperature and showed a species-specific pattern of hourly change in thermal preference. Furthermore, they more frequently used the colder parts of the gradients and spent more time hidden. Lizards experiencing dehydration may suffer a reduction in survival and fitness because of poor thermoregulation. Similarly, they may spend more time hidden, waiting for more favourable weather conditions. Such inactivity may carry ecological costs especially in those regions that undergo either short or prolonged periods of droughts.

×

In recent years, great attention has been paid to many Podarcis species for which the observed intra-specific variability often revealed species complexes still characterized by an unresolved relationship. When compared to other species, P. siculus underwent fewer revisions and the number of species hidden within this taxon may have been, therefore, underestimated. However, recent studies based on genetic and morphological data highlighted a marked differentiation of the populations inhabiting the western Pontine Archipelago. In the present work we used published genetic data (three mitochondrial and three nuclear gene fragments) from 25 Podarcis species to provide a multilocus phylogeny of the genus in order to understand the degree of differentiation of the western Pontine populations. In addition, we analyzed new morphometric traits (scale counts) of 151 specimens from the main islands of the Pontine Archipelago. The phylogenetic analysis revealed five principal Podarcis groups with biogeographic consistency. The genetic distinctiveness of the Podarcis populations of the western Pontine Islands is similar or even more ancient than those observed in numerous other pairs of Podarcis sister species. In the light of these evidences we raise the western Pontine lizards to specific rank; thus they should be referred to as Podarcis latastei.

×

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.

×

Three reptile species were found in Pessegueiro Island (west coast of Portugal): Chalcides bedriagai, Podarcis carbonelli and Blanus cinereus. The first two are confirmations of species already known, but the discovery of B. cinereus is the first record of an insular population in Portugal. The species richness of the island is higher than the expected by its extension. The conservation status of vegetation on the island is poor but the island is nevertheless included in the Natural Park Southwest Alentejo and Costa Vicentina.

×

Species can occupy different realised niches when sharing the space with other congeneric species or when living in allopatry. Ecological niche models are powerful tools to analyse species niches and their changes over time and space. Analysing how species’ realised niches shift is paramount in ecology. Here, we examine the ecological realised niche of three species of wall lizards in six study areas: three areas where each species occurs alone; and three areas where they occur together in pairs. We compared the species’ realised niches and how they vary depending on species’ coexistence, by quantifying niche overlap between pairs of species or populations with the R package ecospat. For this, we considered three environmental variables (temperature, humidity, and wind speed) recorded at each lizard re-sighting location. Realised niches were very similar when comparing syntopic species occurring in the same study area. However, realised niches differed when comparing conspecific populations across areas. In each of the three areas of syntopy, the less abundant species shift its realised niche. Our study demonstrates that sympatry may shift species’ realised niche.

×

While glaciations constituted the major recent paleoclimatic event, inducing multiple oscillations on species’ ranges, future and rapid shifts are expected if global warming predictions are confirmed. Investi-gating the whole temporal spectrum of range shifts is of conservation importance since species suffering contractions during the interglacial periods may continue contracting in a warming scenario; lizards provide excellent models for such analysis. We investigated the historical biogeography of Podarcis car-bonelli, a lacertid lizard endemic to the Western Iberian Peninsula with a fragmented distribution, likely resulting from an important reduction during the Pleistocene and Holocene. We modelled with Maxent its current distribution and projected it to past (Last Interglacial—LIG and Last Glacial Maximum—LGM) and future (2020, 2050 and 2080) scenarios. The consensus models predicted a larger suitable area than the currently occupied, in areas with a high humidity and low maximum temperatures. The LIG model indicated a reduced range restricted to the northern Portuguese coast, and the LGM model, a suitable area larger than the current. After the LGM, areas with suitable climate started regression till present, which is predicted to continue in future, with a northward range shift and a loss of suitable climate from inland zones towards the coast. The range of P. carbonelli may have been oscillating from the northern Portuguese coast to the south and to inland during the Pleistocene. The Portuguese West Atlantic coast, harbouring a substantial part of the species’ genetic diversity, with suitable climate during the LIG and LGM and forecasted to remain in the future, is not currently protected but deserves conservation priority.

×

Research on the taxonomy of European amphibians and reptiles has increased noticeably over the last few decades, indicating the need for recognition of new species and the cancellation of others. This paper provides a critical review of recent changes and draws up a tentative species list.

×

The last species list of the European herpetofauna was published by Speybroeck, Beukema and Crochet (2010). In the meantime, ongoing research led to numerous taxonomic changes, including the discovery of new species-level lineages as well as reclassifications at genus level, requiring significant changes to this list. As of 2019, a new Taxonomic Committee was established as an official entity within the European Herpetological Society, Societas Europaea Herpetologica (SEH). Twelve members from nine European countries reviewed, discussed and voted on recent taxonomic research on a case-by-case basis. Accepted changes led to critical compilation of a new species list, which is hereby presented and discussed. According to our list, 301 species (95 amphibians, 15 chelonians, including six species of sea turtles, and 191 squamates) occur within our expanded geographical definition of Europe. The list includes 14 non-native species (three amphibians, one chelonian, and ten squamates).

×

Currently, we are living an environmental crisis due to the sixth mass species extinction and habitats loss that is being caused by human action. The ex-situ biodiversity monitoring is an alternative tool to conventional methods based on more static and less profitable processes. Therefore, more effective and informative tools are needed that must be supporting the decisive politics. In this work a cost-effective and more efficient methodology is used by combining the ecological niche models (based on the habitat suitability index – HSI) with satellite remote sensing time series data. The work main purpose is to estimate the habitat trends of threatened and emblematic species of different taxonomic groups in Andalusia in the last two decades (2001 – 2019 period). To the calibration of the habitat models, several remote sensing products from MODIS sensor at 5x5km of pixel resolution were used. In general, the models showed a high performance (AUC values between 0.75 and 1), predicting the 60% of the negative trends of the habitat suitability for the total species, showing a habitat regression in the last decades. Among the most affected species, Alytes dickhilleni (amphibian) and Podarcis carbonelli (reptile) stand out, both Ibero-Andalusian endemism whose natural habitat is clearly in decline. The predictor variables that contributed the most were related to the composition and structure vegetation (LC) and with climate and energy balance (ET and LST), marching in mostly of the cases with the species ecology. This methodology represents a promising early warning tool to support management and conservation protocols for threatened species, and thus helps to anticipate the decision-making processes.

×

This study explores the dynamics of a lacertid population in an island environment. The research was conducted on the island of Berlenga, off the Portuguese West Coast. The data collected were compared to previously existing data obtained from mainland areas. The study is interesting for two reasons: first: because it allows observation of Podarcis bocagei berlengensis, an endemic form subjewcted to insular constraints and, second, because the study shows that the knowledge of population dynamics is crucial to the formation of scientifically rooted conservation strategies. Comparison of the population characteristics of Podarcis bocagei berlengensis with those of the mainland species, Podarcis muralis supports the idea that species that are subjected to insular constraints are likely “K-strategist” traits: greater life expectancy, lower rates of population renewal, and very high population densities. The recruitment rate for Podarcis bocagei berlengensis was found to be lower than that of Podarcis muralis, the density of the Podarcis bocagei berlengensis population was higher than the densities of the Podarcis muralis populations, the mortality of eggs was significantyl lower for the island population, and the mortality of adult Podarcis bocagei berlengensis was consistently lower and more constant than the mortality of adult Podarcis muralis. All of these population characteristics indicate that, since its introduction to the island, the population has evoilved to develop some traits of the “K-strategy”. The data also acts as an alarm, providing humans with a way to determine if the population dynamics of Podarcis bocagei berlengensis are being dangerously affected by external factors. It has been noted that the large density decreases seen between 1985 ans 1987 are most likely related to the correlated increases in the yellow-legged-gull populations during the same period. This observation suggests that there is a serious conservation problem that must be addressed on the island of Berlenga. The future of the Podarcis bocagei berlengensis population is unsure unless effective control of the yellow-legged-gull breeding population is achieved.

×

De nombreux travaux ont été publiés sur le régime alimentaire de lézards insectivores. Très peu cependant font explicitement référence au spectre des proies disponibles, ce qui limite singulièrement leur portée écologique. On étudie ici l`écologie trophique de deux populations de Lacertidés insulaires, Podarcis bocagei berlengensis et Lacerta lepida, en reliant les spectres de proies consommées aux ressources effectivement disponibles. Il apparaît que les deux espèces sont caractérisées par un opportunisme alimentaire marqué, bien qu`il existe une certaine sélection des proies fonction de la facilité de capture. Leur importante différence de taille permet de réduire le chevauchement des niches alimentaires et favorise la coexistence de ces deux espèces dont l`abondance est probablement réglée par une forte compétition intraspécifique.

×

During two journeys from 27.04. – 07.05.2008 and from 21.04. – 27.04.2012, I visited several parts pf Spain together with some friends of mine. We focused on the lizards of the Iberiasn Peninsula. Specifically, we wanted to make some beautiful pictures of the Ocellated Lizatrds Timon lepidus and Timon nevadensis, which unfortunately did not always succeed on the first trip. In the following article, I briefly present the lizards of the family Lacertidae that were found during the two journeys together with some of their localities.