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Conspicuous body colors and color polymorphism have been hypothesized to increase rates of speciation. Conspicuous colors are evolutionary labile, and often involved in intraspecific sexual signaling and thus may provide a raw material from which reproductive isolation can easily evolve, while polymorphism could favor rapid evolution of new lineages through morphic speciation. Here, we investigated the influence of the presence/absence of conspicuous colorations, and of color polymorphism on the speciation of Lacertids. We used several state-dependent diversification models, and showed that, regardless of the methods, conspicuous colorations and color polymorphism were not related to species speciation. While the lack of correlation between conspicuous colorations and speciation rates is in line with most of the literature testing this hypothesis, the results for color polymorphism contradict previous studies, and question the generality of the morphic speciation hypothesis.

AimDiscontinuity in the distribution of genetic diversity (often based on mtDNA) is usually interpreted as evidence for phylogeographic breaks, underlying vicariant units. However, a misleading signal of phylogeographic break can arise in the absence of barrier to gene flow, under mechanisms of isolation by distance (IBD). How and under which conditions phylogeographic breaks can be reliably differentiated from populations evolving under IBD remain unclear. Here, we use multi-locus sequence data from a widely distributed lizard species to address these questions in an empirical setting.LocationMoroccoTaxonSpiny-footed lizard (Acanthodactylus erythrurus), Squamata: LacertidaeMethodsUsing 325 samples from 40 localities, we identified genetic discontinuities withinA. erythrurusbased on a mitochondrial fragment and nine nuclear markers independently. Using the nuclear markers, we then applied linear regression models to investigate whether genetic divergence could be explained by geographical distances alone, or barriers to gene flow (real phylogeographic breaks).ResultA. erythrurusis characterized by an important mitochondrial diversity, with 11 strongly supported phylogeographic lineages with a crown age of 6 Mya. Nuclear markers, however, yielded weak phylogenetic support for these lineages. Using clustering methods based on genotypes at nine nuclear loci, we identified phylogeographic clusters that were partly discordant with the mtDNA lineages. Tests of IBD delimited at least four groups of populations separated by barriers to gene flow, but unambiguous separation of vicariance from IBD remained challenging in several cases.Main conclusionsThe genetic diversity ofA. erythrurusoriginates from a mix of IBD and vicariance, which were difficult to distinguish, and resulted in similar levels of mitochondrial differentiation. These results highlight that phylogeographic breaks inferred from mitochondrial data should be further investigated using multi-locus data and explicit testing to rule out alternative processes generating discontinuities in mitochondrial diversity, including IBD. We identified four groups of populations withinA. erythrurus, separated by barriers to gene flow, but even using nine independent nuclear makers the power of our approach was limited, and further investigation using genome-wide data will be required to resolve the phylogeographic history of this species.

Linnaean and Wallacean shortfalls (Uncertainties on species taxonomy and distribution, respectively) are major factors hampering efficient conservation planning in the current context of biodiversity erosion. These shortfalls concern even widespread and abundant species in relatively well-studied regions such as the Mediterranean biodiversity hotspot which still hosts a large fraction of unrecognised biodiversity, notably in small vertebrates. Species delimitations have long been based on phylogenetic analyses of a small number of standard markers, but accurate lineage identification in this context can be obscured by incomplete lineage sorting, introgression or isolation by distance. Recently, integrative approaches coupling various sets of characters or analyses of contact zones aiming at estimating reproductive isolation (RI) have been advocated instead. Analyses of introgression patterns in contact zone with genomic data represent a powerful way to confirm the existence of independent lineages and estimate the strength of their RI at the same time. The Spiny-footed Lizard Acanthodactylus erythrurus (Schinz, 1833) is widespread in the Iberian Peninsula and the Maghreb and exhibits a large amount of genetic diversity, although the precise number and distribution of its genetic lineages remain poorly understood. We applied a RADseq approach to obtain a genome wide SNPs dataset on a contact zone in central Morocco between the previously described Rif and Middle-Atlas lineages. We show that these two lineages exhibit strong RI across this contact zone, as shown by the limited amount and restricted spatial extant of gene flow. We interpret these results as evidence for species-level divergence of these two lineages. Our study confirms the usefulness of RADseq approaches applied on contact zones for cryptic diversity studies and therefore to resolve Linnaean and Wallacean shortfalls.

Background The orogeny of the eastern Mediterranean region has substantially affected ecological speciation patterns, particularly of mountain-dwelling species. Mountain vipers of the genus Montivipera are among the paramount examples of Mediterranean neo-endemism, with restricted ranges in the mountains of Anatolia, the Levant, Caucasus, Alborz, and Zagros. Here we explore the phylogenetic and ecological diversification of Montivipera to reconstruct its ecological niche evolution and biogeographic history. Using 177 sequences of three mitochondrial genes, a dated molecular phylogeny of mountain vipers was reconstructed. Based on 320 occurrence points within the entire range of the genus and six climatic variables, ecological niches were modelled and used to infer ancestral niche occupancy. In addition, the biogeographic history and ancestral states of the species were reconstructed across climate gradients. Results Dated phylogenetic reconstruction revealed that the ancestor of mountain vipers split into two major clades at around 12.18 Mya followed by multiple vicariance events due to rapid orogeny. Montivipera colonised coastal regions from a mountain-dwelling ancestor. We detected a highly complex ecological niche evolution of mountain vipers to temperature seasonality, a variable that also showed a strong phylogenetic signal and high contribution in niche occupation. Conclusion Raising mountain belts in the Eastern Mediterranean region and subsequent remarkable changes in temperature seasonality have led to the formation of important centres of diversification and endemism in this biodiversity hotspot. High rates of niche conservatism, low genetic diversity, and segregation of ranges into the endemic distribution negatively influenced the adaptive capacity of mountain vipers. We suggest that these species should be considered as evolutionary significant units and priority species for conservation in Mediterranean mountain ecosystems.

We examined the contact zone of two parapatric species of grass snake (Natrix astreptophora and Natrix helvetica) in southern France. To this end, we used comprehensive sampling, analysed mtDNA sequences and microsatellite loci, and built Species Distribution Models for current and past climatic conditions. The contact zone had established by the mid-Holocene during range expansions from glacial refuges in the Iberian Peninsula (N. astreptophora) and southern or western France (N. helvetica). The contact zone represents a narrow bimodal hybrid zone, with steep genetic transition from one taxon to the other and rare hybridization, supporting species status for N. astreptophora and N. helvetica. Our results suggest that the steepness of the clines is a more robust tool for species delimitation than cline width. In addition, we discovered in western France, beyond the hybrid zone, a remote population of N. helvetica with genetic signatures of hybridization with N. astreptophora, most likely the result of human-mediated long-distance dispersal. For N. helvetica, we identified a southern and a northern population cluster, connected by broad-scale gene flow in a unimodal hybrid zone running across France. This pattern either reflects genetic divergence caused by allopatry in two microrefuges and subsequent secondary contact or introgression of foreign alleles into the southern cluster.

We examined the taxonomy of the minute desert geckos of the Tropiocolotes nat-tererispecies complex using the largest morphological sampling, and the first mo-lecular assessment of intraspecific diversity within this complex. We examined variation in mitochondrial and nuclear markers (12S, ND2, c- mosand MC1R) of 30 samples and analyzed the external morphology of 202 specimens, from across the entire distribution range of the complex from Egypt, Israel, Jordan and Saudi Arabia. We recognize two species under the name T. nattereri. We thus hereby describe a new species, T. yomtovisp. n., and we redefine and redescribe T. nattereri, for which we designate a neotype. The species diversity in the genus Tropiocolotes increases to 15., This work was supported by the Gans Collections and Charitable Fund Inc. [M.A.R- J. grant], SYNTHESYS+, Synthesis of Systematic Resources funded by the European Commission [M.A.R- J. grants: ES- TAF- 1276; GB- TAF- 2393; CZ- TAF- 1260; DE- TAF- 2418], the Rector scholarship, Tel Aviv University [M.A.R- J. postdoctoral fellowship] and the Alexander and Eva Lester Fund scholarship, I. Meier Segals Garden for Zoological Research [M.A.R- J. postdoctoral fellowship].

International audience; Aim: The biogeographic history of the Sahara-Sahel desert is tightly linked to its extreme and fluctuating palaeoclimate and diverse topography. For the mesic species inhabiting the region, coastal areas and the Nile Valley are perceived as the main pathways to disperse through desert habitats, but past connections may have also occurred throughout currently isolated mountain regions. Herein, we test the trans-Sahara mountain corridor hypothesis (i.e., mesic connectivity across Central Sahara highlands) and its role in the diversification of a small terrestrial vertebrate.Location: North Africa and Arabia.Taxon; Acanthodactylus boskianus (Squamata: Lacertidae).Methods: We integrated multi-locus mitochondrial and nuclear phylogenies with species’ climate-niche modelling, including palaeo-projections. Genetic analyses aimed to assess the species’ genetic structure, identify its main mitochondrial lineages and nuclear diversity, and reconstruct its ancestral biogeography. Species’ climate-niche stability was modelled independently for the Late Pleistocene-Holocene and the Plio-Pleistocene, to infer historical climatic refugia and dispersal corridors.Results: Four spatially structured mitochondrial lineages, integrating several parapatric sub-lineages, originated during the Plio-Pleistocene. Nuclear data revealed nine potential candidate species. Climatic refugia were located in mountains and desert fringes, remaining consistent for the Late Pleistocene-Holocene and the Plio-Pleistocene. Recurrent North-South climatic corridors were located along the desert periphery, while others less frequent were found across Central Sahara. Ancestral biogeography analyses recovered a recent Pleistocene colonization of the Sahel throughout eastern Sahara and either Sahara or Sahel origin for Central Sahara populations.Main conclusions: Species’ diversification was triggered by a combination of Plio-Pleistocene climatic cycles across a complex topographic region, where mountains acted as the main diversification hotspots. The historical role of Central Sahara highlands as main non-peripheral mesic refugia was corroborated. In addition, intermittent climatic connections linked Mediterranean and Sahel ecoregions with Central Sahara refugia, suggesting the existence of alternative trans-Sahara dispersal routes to the putative coastal and Nile corridors.

The slow-worm lizards (Anguis) comprise five species occurring throughout most of the Western Palearctic. Although these species are relatively uniform morphologically – with the exception of A. cephallonica, which exhibits a quite unique morphology – they are genetically deeply divergent. Here, we provide detailed distribution maps for each species and discuss their biogeography and conservation based on updated genetic data and a robust distribution database. We pay particular attention to the so called ‘grey zone’, which typically represents secondary contact zones and in some cases confirmed or presumed hybrid zones. Four of the five species live in parapatry, while only two species, A. cephallonica and A. graeca from the southern Balkans occur in partial sympatry. Further research should focus on the eco-evolutionary interactions between species in contact, including their hybridization rates, to reveal deeper details of the slow-worm evolutionary and natural history.

Cryptic phylogeographic diversifications provide unique models to examine the role of phylogenetic divergence on the evolution of reproductive isolation, without extrinsic factors such as ecological and behavioural differentiation. Yet, to date very few comparative studies have been attempted within such radiations. Here, we characterize a new speciation continuum in a group of widespread Eurasian amphibians, the Pelobates spadefoot toads, by conducting multilocus (restriction site associated DNA sequencing and mitochondrial DNA) phylogenetic, phylogeographic and hybrid zone analyses. Within the P. syriacus complex, we discovered species‐level cryptic divergences (>5 million years ago [My]) between populations distributed in the Near‐East (hereafter P. syriacus sensu stricto [s.s.]) and southeastern Europe (hereafter P. balcanicus), each featuring deep intraspecific lineages. Altogether, we could scale hybridizability to divergence time along six different stages, spanning from sympatry without gene flow (P. fuscus and P. balcanicus, >10 My), parapatry with highly restricted hybridization (P. balcanicus and P. syriacus s.s., >5 My), narrow hybrid zones (~15 km) consistent with partial reproductive isolation (P. fuscus and P. vespertinus, ~3 My), to extensive admixture between Pleistocene and refugial lineages (≤2 My). This full spectrum empirically supports a gradual build up of reproductive barriers through time, reversible up until a threshold that we estimate at ~3 My. Hence, cryptic phylogeographic lineages may fade away or become reproductively isolated species simply depending on the time they persist in allopatry, and without definite ecomorphological divergence.

[Aim] Deserts are generally perceived as areas of low diversity, and hence receive little attention from researchers and conservationists. Squamates are the dominant group of vertebrates in arid regions, and as such represent an ideal model to study biodiversity patterns in these areas. We examine spatial patterns of diversity, evolutionary history and endemism of terrestrial squamates of the Arabian Peninsula and test hypotheses on the role of topography and history of isolation so as to identify possible environmental drivers of diversification., [Location] The Arabian Peninsula., [Taxon] Squamate reptiles (Squamata; lizards and snakes)., [Methods] We generated distribution maps for all Arabian squamate species (including yet undescribed) and reconstructed their phylogenetic relationships using existing and newly produced genetic data for nearly all the species. We assessed patterns of the distribution of species richness, phylogenetic diversity and phylogenetic endemism across the peninsula to identify areas that could be considered evolutionary or endemicity hotspots for squamates. We evaluated community turnover across the peninsula and assessed the possible environmental drivers affecting the diversity of Arabian squamates in a regression framework., [Results] The main hotspots of Arabian squamate diversity are mostly along the mountains that rim the peninsula while the most arid, central regions support a low diversity of species. The distribution of the phylogenetic diversity mirrors that of the species richness. Phylogenetic endemism is also highest in the mountains, especially when only endemic species are analysed. The deserts of northern Arabia are poor in terms of species richness and they show low connectivity to the peninsular communities. Topographic heterogeneity is the strongest predictor for Arabian squamates, followed by elevation. There is no correlation between richness and temperature., [Main conclusions] The mountains of Arabia support rich and unique squamate communities that are dominated by local radiations of closely related and narrow-ranging species. In particular, the Asir Mountains of SW Arabia, Dhofar Province of Oman and the Hajar Mountains of northern Oman and UAE show unprecedented levels of squamate endemism and phylogenetic endemism. While many generalist species range across Arabia, a low number of species is shared between the peninsula and mainland Asia, indicating an effective isolation of the Arabian fauna. Squamate richness is highest in heterogeneous, topographically complex habitats., Field work carried out for this project in Saudi Arabia was supported by Saudi Wildlife Authority (SWA). We are thankful to Taif University, Saudi Arabia, for support under Researcher Supporting project number TURSP-2020/06. The work of JŠ was supported by the Czech Science Foundation (GACR, project number 18–15286Y) and the Ministry of Culture of the Czech Republic (DKRVO 2019–2023/6.VII.c, 00023272); SC was supported by grant PGC2018-098290-B-I00 (MCIU/AEI/FEDER, UE); BB-C was funded by FPU grant FPU18/04742 (MICIU, Spain); HT-C and MS-R were funded by FPI grants (MINECO, Spain; BES-2016-078341 and BES-2013-064248, respectively), PT was supported by FCT (DL57/2016/CP1440/CT0008).

Our study seeks to: (1) reduce biodiversity knowledge gaps in amphibians from desert and arid regions; (2) quantify species diversity and detect potential cryptic diversity; (3) identify environmental correlates of amphibian richness distribution, and (4) identify diversity hotspots. DNA barcoding and spatial modelling were integrated to map observed and predicted amphibian richness in Mauritania, Africa. We built two DNA barcoding libraries using one mitochondrial (COI) and one nuclear marker (RAG1). Taxon richness was calculated using species delimitation methods. A generalised linear model was employed to identify environmental correlates of amphibian richness and the distribution of diversity hotspots was predicted. We found a total of 16 anuran taxa with Afrotropic affinities, and two genera and four species were added for the amphibian list of Mauritania. Potential cryptic diversity was detected in Hoplobatrachus occipitalis. Amphibian richness was positively correlated with proximity to savannah, gravel floodplains, and with presence of seasonal wetlands, and negatively with proximity to dunes. Major diversity hotspots were predicted in southern Mauritania. Barcoding methods for both genetic markers successfully identified the taxonomic identity of specimens, also uncovering cryptic diversity in the amphibians of the Sahara-Sahel ecoregions. Amphibian richness in Mauritania increases southwards and it is mostly concentrated in areas under pressure due to habitat conversion, lacking legal protection. The combination of DNA barcoding with spatial modelling can be easily applied to any desert system to address pressing needs for research on biodiversity distribution., Funding provided by National Geographic Society (CRE-7629-04, CRE-8412-08, GEFNE-53-12), Mohammed bin Zayed Species Conservation Fund (11052709, 11052707, 13257467), Rufford Foundation (SG-15399-1, SG-17893-1), Fundação para a Ciência e Tecnologia (FCT: PTDC/BIA-BEC/099934/2008, PTDC/BIA-BIC/2903/2012), FEDER through COMPETE-Operational Programme for Competitiveness Factors (FCOMP-01-0124-FEDER-008917, -028276), and by AGRIGEN–NORTE-01-0145-FEDER-000007, supported by Norte Portugal Regional Operational Programme (NORTE2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). Research conducted in the scope of the LIA “Biodiversity and Evolution”. Individual support given by FCT (contracts DL57/2016/CP1440/CT0010, IF/01425/2014, and CEECINST/00014/2018/CP1512/CT0001).

Plate tectonics constitute one of the main mechanisms of biological diversification on Earth, often being associated with cladogenetic events at different phylogenetic levels, as well as with exchange of faunas and floras across previously isolated biogeographic regions. North Africa and Arabia share a complex geological history that dates back to the break-up of the Arabian plate from the African plate ~30–25 Mya, followed by various geological events, such as the formation of the Red Sea or the connection between the African, Arabian and Eurasian plates. Species with Saharo-Arabian distributions have shown a close association between their evolutionary history and these geological events. In this study, we investigate the systematics, biogeography and evolution of the genus Tropiocolotes, a group of small ground-dwelling geckos, comprised by 12 species distributed from the Atlantic coast of North Africa to southwestern Iran. Species delimitation analyses uncovered the existence of high levels of undescribed diversity, with forms here considered at the species level including Tropiocolotes tripolitanus (Mauritania and southern Morocco), T. nattereri (southern Israel) and T. scorteccii (Yemen and Oman). Phylogenetic and biogeographic analyses recovered two main clades, an exclusively African clade and a Saharo–Arabian clade, that split ~25 Mya following the vicariant event mediated by the separation of the Arabian and African plates. The complex geological activity around the Red Sea is associated with the diversification within the Saharo-Arabian clade, including the colonization of North Africa from a second Tropiocolotes group. Results also provide new insights into the geographic distribution of Tropiocolotes nubicus, previously considered as exclusively associated to the Nile River valley, extending its known distribution further west, up to the Central Mountains of the Sahara. Accordingly, the Nile River seems to act as a major biogeographic barrier, separating Tropiocolotes nubicus and T. steudneri in their western and eastern margins, respectively., LM was funded by Fundação para a Ciência e Tecnologia (FCT) through a PhD grant (SFRH/BD/89820/2012) financed by Programa Operacional Potencial Humano (POPH) – Quadro de Referência Estratégico Nacional (QREN) from the European Social Fund and Portuguese Ministério da Educação e Ciência. The study was funded by grants CGL2015-70390-P and PGC2018-098290-B-I00 from the Ministerio de Economía y Competitividad, Spain (cofunded by FEDER) to and grant 2017-SGR-00991 from the Secretaria d’Universitats i Recerca del Departament d’Economia i Coneixement de la Generalitat de Catalunya to SC.

International audience; Aim: To test the hypothesis that spatial variations in climate and land use explain the distribution and diversity of reptiles’ ecological traits in a biodiversity hotspot of the Mediterranean basin.Location: French Mediterranean region.Taxon: Reptiles (25 species).Methods: We defined 288 species assemblages from 27,858 opportunistic occurrence records within 10 × 10 km square grid cells. Using a RLQ analysis, we investigated the distribution of nine ecological traits describing reptiles’ reproductive, dietary and behavioural strategies along environmental gradients formed by 10 climatic, topographic and land‐use descriptors. After homogenizing survey effort through rarefaction, we used generalized additive models to assess variations in species richness and several measures of functional diversity and composition along these gradients.Results: Although ecological traits were not structured by environmental gradients at a species level, species richness and all measures of functional diversity varied nonlinearly with climate, elevation and secondarily land use. Species richness and body size peaked at intermediate altitudes, indicating a climatic transition zone between Mediterranean and medio‐European herpetofaunas. Conversely, functional diversity increased from Mediterranean plains, dominated by urbanization and agriculture, to higher elevations. These changes were associated with shifts towards less productive, more diurnal and more forest‐related species.Main conclusions: Species‐scale patterns are insufficient to assess regional variations in ecological traits in space. Our results support the hypothesis that climatic limitations in species’ distributions, rather than environmental filtering, explain the taxonomic and ecological diversity of reptiles at a regional scale. Although secondary to climate, land abandonment has a strong structuring effect which may contribute to homogenize the composition of reptile assemblages.

International audience

The monitoring of introduced species is becoming more important as global trade intensifies. Although ants make up a larger proportion of species on the list of the most invasive species in the world compared with other groups, little is known about the occurrence of those introduced in France, especially inside heated buildings. Here we review the literature available for mainland France and Belgium and report the results of a survey conducted with the help of tropical building managers between 2014 and 2016. We report for the first time in France the presence of Technomyrmex vitiensis and Plagiolepis alluaudi in multiple greenhouses. Technomyrmex difficilis was also found in one greenhouse for the first time in Europe. The diversity of introduced ants in greenhouses is very low, and these buildings are most often dominated by one or two species. We compared the most recent data and those collected throughout the twentieth century and showed that ant communities have changed substantially. Greenhouses could be responsible for the introduction of invasive species because they regularly import exotic plants, but we found no evidence that the three species of invasive ants present outdoors in France were introduced from greenhouses, where they rarely occur. We also report that introduced ants are pests in greenhouses because they disperse scale insects and kill biological control agents. The suppression of these ants could ease the maintenance of plants inside greenhouses.

International audience; The subfamily Uromastycinae within the Agamidae is comprised of 18 species: three within the genus Saara and 15 within Uromastyx. Uromastyx is distributed in the desert areas of North Africa and across the Arabian Peninsula towards Iran. The systematics of this genus has been previously revised, although incomplete taxonomic sampling or weakly supported topologies resulted in inconclusive relationships. Biogeographic assessments of Uromastycinae mostly agree on the direction of dispersal from Asia to Africa, although the timeframe of the cladogenesis events has never been fully explored. In this study, we analysed 129 Uromastyx specimens from across the entire distribution range of the genus. We included all but one of the recognized taxa of the genus and sequenced them for three mitochondrial and three nuclear markers. This enabled us to obtain a comprehensive multilocus time‐calibrated phylogeny of the genus, using the concatenated data and species trees. We also applied coalescent‐based species delimitation methods, phylogenetic network analyses and model‐testing approaches to biogeographic inferences. Our results revealed Uromastyx as a monophyletic genus comprised of five groups and 14 independently evolving lineages, corresponding to the 14 currently recognized species sampled. The onset of Uromastyx diversification is estimated to have occurred in south‐west Asia during the Middle Miocene with a later radiation in North Africa. During its Saharo‐Arabian colonization, Uromastyx underwent multiple vicariance and dispersal events, hypothesized to be derived from tectonic movements and habitat fragmentation due to the active continental separation of Arabia from Africa and the expansion and contraction of arid areas in the region.

We examined phylogeographic differentiation of the red-eyed grass snake (Natrix astreptophora) using 1984 bp of mtDNA and 13 microsatellite loci from specimens collected across its distribution range in southwestern Europe and northwestern Africa. Based on phylogenetic analyses of mtDNA, European N. astreptophora constituted the sister clade to a weakly supported North African clade comprised of two deeply divergent and well-supported clades, one corresponding to Moroccan snakes and the other to snakes from Algeria and Tunisia. This tripartite differentiation was confirmed by analyses of microsatellite loci. According to a fossil-calibrated molecular clock, European and North African N. astreptophora diverged 5.44 million years ago (mya), and the two Maghrebian clades split 4.64 mya. These dates suggest that the radiation of the three clades was initiated by the environmental changes related to the Messinian Salinity Crisis and the reflooding of the Mediterranean Basin. The differentiation of N. astreptophora, with distinct clades in the Iberian Peninsula and in the western and eastern Maghreb, corresponds to a general phylogeographic paradigm and resembles the differentiation found in another co-distributed Natrix species, the viperine snake (N. maura). Despite both species being good swimmers, the Strait of Gibraltar constitutes a significant biogeographic barrier for them. The discovery that North Africa harbours two endemic lineages of N. astreptophora necessitates more conservation efforts for these imperilled snakes.

Biodiversity conservation requires strategies that encompass a variety of land uses and habitat diversity. In this study, we used sites of high ecological interest identified on the basis of the distribution of priority plant and vertebrate species to assess the implications of habitat diversity for conservation management in the Mediterranean mosaic landscape. 40% of the priority species occur in open habitats that depend on continued human presence and low-intensity land-use activities. Furthermore, 70% of the sites have more than one species habitat and 15% of sites contain more than four different species habitats. By explicitly integrating localized habitat variation, conservation planning can address the multiple conservation issues at stake in regions of high landscape diversity to provide clear and effective management objectives.

Batesian mimicry, with its highly colorful species and astonishing mimic-model resemblance, is a canonical example of evolution by natural selection. However, Batesian mimicry could also occur in inconspicuous species and rely on subtle resemblance. Although potentially widespread, such instances have been rarely investigated, such that the real frequency of Batesian mimicry has remained largely unknown. To fill this gap, we developed a new approach using deep learning to quantify the resemblance between putative mimics and models from photographs. We applied this method to quantify the frequency of Batesian mimicry in Western Palearctic snakes. Potential mimics were revealed by an excess of resemblance with sympatric venomous snakes compared to random expectations. We found that 8% of the non-venomous species were potential mimics, among which all were imperfect mimics. This study is the first to quantify the frequency of Batesian mimicry in a whole community of vertebrates, and shows that even concealed species can be reliably identified as potential models. Our approach should prove useful to detect mimicry in other communities, and more generally it highlights the benefits of deep learning for quantitative studies of phenotypic resemblance.

Background and aims Orchids are known to be particularly sensitive to environmental changes due to their narrow ranges of secondary successional habitats. Lack of data at the community level limits our ability to evaluate how traits of different species influence their responses to habitat change. Here, we used a diachronic survey of Mediterranean orchid communities in Corsica to examine this question. Methods Using data from two field surveys conducted 27 years apart (1982-84 and 2009-11) at the same 45 sites in Corsica, we evaluated the impact of increase in woody plant cover (WPC) on (i) the richness and composition and (ii) the local extinction/colonization dynamics of orchids. We applied a Bayesian multispecies site-occupancy model to each of the 36 orchid species recorded at these sites to estimate the detection probability of each species, enabling us to account for under-detection in estimating their dynamics. Key results Between 1982 and 2011, WPC changed at 82·3 % of sites (increasing at 75·6 %, decreasing at 6·7 %). Despite marked changes in composition of orchid communities at the local scale, no significant change was detected in species richness at the regional scale. Canopy closure affected the probability of new colonization of sites, but had no significant influence on the probability of local extinction. However, the abundance of shade-intolerant species declined more sharply than that of shade-requiring species. Among orchid species, the detection probability was significantly and positively correlated with population density and plant height. Conclusions This study reveals contrasted dynamics of orchid communities between local and regional scales in Corsica. Although high turnover in communities was found at the local scale, regional species richness was maintained despite major land-use changes. Conserving landscape mosaics could provide locally suitable habitats for orchids of different ecologies to maintain diversity at larger spatial scales.

In the south of France, the so-called climate hiatus from 1998 to 2013 was associated with a late winter cooling which has affected the phenology of several reptiles and amphibian species, delaying their dates of first appearances in spring. This episode has been related to a period of frequently negative values of the North Atlantic Oscillation index (NAOi). The recent increase of this index after this episode marks the end of the “hiatus” and provides an opportunity to verify the impact of the North Atlantic Oscillation (NAO) on the fauna of the North Mediterranean region. Most of the emergence dates of amphibians and reptiles in spring have rapidly advanced from 1983 to 1997 and then receded or stabilized from 1998 to 2010. They began to advance again since 2010. These phenological changes covary with the temperature of February–March in the study area, which is itself related to the variations of the NAO index. These changes confirm the influence of the NAO on the phenology of terrestrial organisms in northern Mediterranean where its influence is sometimes assumed to be attenuated.

The diversity of animal visual displays has intrigued scientists for centuries. Sexual selection theory has explained some of this diversity, yet most of this effort has focused on simple aspects of signal design, such as color. The evolution of complex patterns that characterize many sexual displays remains largely unexplained. The field of empirical aesthetics, a subdiscipline of cognitive psychology, has shown that humans are attracted to visual images that match the spatial statistics of natural scenes. We investigated whether applying this result to animals could help explain the diversification of complex sexual signaling patterns. We used Fourier analysis to compare the spatial statistics of body patterning in ten species of darters (Etheostoma spp.), a group of freshwater fishes with striking male visual displays, with those of their respective habitats. We found a significant correlation between the spatial statistics of darter patterns and those of their habitats for males, but not for females. Our results suggest that visual characteristics of natural environments can influence the evolution of complex patterns in sexual signals.

International audience

International audience; Although classified among the greatest threats to the world's biodiversity, the effects of land use and their scale dependency are left unexplored in many taxonomic groups. Reptiles are among the most data-deficient vertebrates in this respect, although their ecological traits make them highly sensitive to habitat modifications. We tested whether land use gradients shape the distributions of Mediterranean reptiles at regional and local scales, and whether species' ecological traits and phylogeny explain these patterns. Reptiles are generally rare and hard to survey through standardized protocols. We overcame these obstacles by modeling an original data set of 18164 opportunistic occurrence records for 14 reptile species with spatially-explicit point process models incorporating known sources of sampling heterogeneity and spatially autocorrelated error. At a regional scale, reptiles favored open habitats and tended to avoid urban areas. At a local scale, the persistence of open habitats did better than forest resulting from land abandonment in maintaining reptiles within a heavily anthropogenic matrix. Contrary to our expectations, the absence of any clear trait or phylogenetic signals suggests that these responses are mediated by a complex interplay between species' ecology and regional biogeographic history. These results demonstrate that reptile responses to land use are scale-dependent and locally exacerbated when anthropogenic pressure is high. We further show that land abandonment is insufficient to preserve reptiles in the face of anthropogenic pressures unless patches of suitable habitat are effectively maintained. Eventually, our study further illustrates the effectiveness of volunteer-based opportunistic sampling in testing hypotheses on the determinants of rare species' distributions.

The grass snake (Natrix natrix) is Europe's most widely distributed and, in many regions, most common snake species, with many morphologically defined subspecies. Yet, the taxonomy of grass snakes is relatively little studied and recent work has shown major conflicts between morphologically defined subspecies and phylogeographical differentiation. Using external morphology, osteological characters, and information from 13 microsatellite loci and two mitochondrial markers, we examine differentiation of the subspecies N. n. astreptophora from the North African Maghreb region, the Iberian Peninsula and neighbouring France. According to previous studies, N. n. astreptophora corresponds to a deeply divergent mitochondrial clade and constitutes the sister taxon of all remaining grass snakes. In the French Pyrenees region, there is a contact zone of N. n. astreptophora with another subspecies, N. n. helvetica. Our analyses of microsatellites and mitochondrial DNA reveal that the distribution ranges of the two taxa abut there, but both hybridize only exceptionally. Even though many morphological characters are highly variable and homoplastic in grass snakes, N. n. astreptophora differs consistently from all other grass snakes by its reddish iris coloration and in having significantly fewer ventral scales and another skull morphology. Considering further the virtual absence of gene flow between N. n. astreptophora and N. n. helvetica, and acknowledging the morphological distinctiveness of N. n. astreptophora and its sister group relationship to all remaining subspecies of grass snakes, we conclude that Natrix astreptophora (Seoane, 1884) should be recognized as a distinct species. Further research is needed to explore whether N.astreptophora is polytypic because a single sample of N.astreptophora from Tunisia turned out to be genetically highly distinct from its European conspecifics.

International audience; Recent integration of ecological niche models in phylogeographic studies is improving our understanding of the processes structuring genetic variation across landscapes. Previous studies on the amphibian Bufotes boulengeri boulengeri uncovered a surprisingly weak intraspecific differentiation across the Maghreb region. We widely sampled this species from Morocco to Egypt and sequenced one nuclear and three mitochondrial (mtDNA) genes to determine the level of genetic variability across its geographic range. We evaluated these data with ecological niche modeling to reveal its evolutionary history in response to climate change during the Quaternary. Our results highlight some mtDNA phylogeographic structure within this species, with one haplogroup endemic to coastal Morocco, and one haplogroup widely distributed throughout North Africa. No or little genetic differentiation is observed between isolated populations from the Hoggar Mountains, the Sabha district and the islands of Kerkennah and Lampedusa, compared to others populations. This can be explained by the expansion of the distribution range of B. b. boulengeri during glacial periods. This might have facilitated the species’ dispersal and subsequent gene flow between most North African localities.

International audience; Highlands, hydrographic systems and coastal areas have been hypothesised to form corridors across the hyperarid Sahara desert in North Africa, allowing dispersal and gene flow for non-xeric species. Here we aim to provide a genetic test for the trans-Saharan corridor model, and predict the location and stability of ecological-corridors, by combining phylogeography and palaeoclimatic modelling. The model was the Psammophis schokari (Schokari sand racer) group, fast-moving and widely distributed generalist colubrids occurring mostly in arid and semiarid scrublands. We combined dated phylogenies of mitochondrial and nuclear markers with palaeoclimatic modelling. For the phylogeographic analysis, we used 75 samples of P. schokari and P. aegyptius, and Bayesian and Maximum-Likelihood methods. For the ecological models, we used Maxent over the distribution of P. schokari and West African lineages. Models were projected to past conditions (mid Holocene, Last Glacial Maximum and Last Inter-Glacial) to infer climatic stable areas. Climatic stability was predicted to be mostly restricted to coastal areas and not spatially continuous. A putative temporary trans-Saharan corridor was identified in Eastern Sahara, with a more stable one along the Atlantic coast. Six parapatric lineages were identified within P. schokari, four occurring in North Africa. These likely diverged during the Pliocene. The Tamanraset River might have been a vicariant agent. African lineages may have experienced further subsequent diversification during the late Pleistocene. The main P. schokari refugia were probably located along the northern margins of the Sahara, allowing its North-to-South colonization. Trans-Saharan corridors seem to have played a role in P. schokari biogeography, allowing colonization of central Saharan mountains and Sahel. Some might have worked as refugia, and even the most stable corridors may have sections working as filters, depending on each climatic phase. We expect the use of trans-Saharan corridors to decrease for more mesic species or with less dispersal capabilities.

We studied the phylogeography of the Sahara frog in North Africa. We widely sampled frogs from Morocco to Tunisia (195 individuals) and sequenced two mitochondrial (16S and CO1) and one nuclear (Rag1) genes. Our results confirm that Moroccan populations of Pelophylax saharicus are genetically distinct from Algerian ones. Specimens from Alger and Djelfa (central Algeria) are genetically closer to Moroccan specimens than to east Algerian ones, and the split between these two lineages may have occurred approximately 2.6 Mya. A similar pattern of differentiation was observed in several other species and was hypothesized to be linked to the formation of the fossil island called the ‘Edough Peninsula’ in eastern Algeria around 4.2 Ma and then to have been reinforced by Pleistocene climatic changes. At the Moroccan scale, we found a low level of genetic diversity and no clear phylogeographic pattern within P. saharicus. However, our SAShA analyses revealed a mixture of random and underdistributed haplotypes, which may indicate a complex population genetic or biogeographic history.

Herps, especially amphibians, are particularly susceptible to climate change, since temperature tightly controls many parameters of their biological cycle – above all, their phenology. The timing of herps’ activity or migration period – in particular the dates of their first appearance in spring and first breeding – and the shift to earlier dates in response to warming since the last quarter of the 20th century has often been described up to now as a nearly monotonic trend towards earlier phenological events. In this study, we used citizen science data opportunistically collected on reptiles and amphibians in the northern Mediterranean basin over a period of 32 years to explore temporal variations in herp phenology. For 17 common species, we measured shifts in the date of the species’ first spring appearance – which may be the result of current changes in climate – and regressed the first appearance date against temperatures and precipitations. Our results confirmed the expected overall trend towards earlier first spring appearances from 1983 to 1997, and show that the first appearance date of both reptiles and amphibians fits well with the temperature in late winter. However, the trend towards earlier dates was stopped or even reversed in most species between 1998 and 2013. We interpret this reversal as a response to cooling related to the North Atlantic Oscillation (NAO) in the late winter and early spring. During the positive NAO episodes, for certain species only (mainly amphibians), the effect of a warm weather, which tends to advance the phenology, seems to be counterbalanced by the adverse effects of the relative dryness. This article is protected by copyright. All rights reserved.

Aim We explored the phylogenetic relationships of species of Mesalina, using one nuclear and two mitochondrial loci. This genus of lacertid lizards is widely distributed in North Africa and the Middle East and our goal was to develop a scenario capable of explaining the current distribution and evolutionary patterns within the genus in the context of the wider historical biogeography of the region. Location North Africa and the Middle East. Methods The assembled dataset consisted of 193 Mesalina individuals, representing 12 species distributed across the geographical range of the genus. Bayesian and maximum likelihood methods were used to support phylogenetic inferences on two mitochondrial (cytochrome b and 16S ribosomal RNA) and one nuclear (beta-fibrinogen intron 7) markers. Palaeogeographical and palaeoclimatic data were used to support the inferred phylogeographical patterns. Results Mesalina lizards exhibit high genetic diversity and complex phylogenetic patterns, leading to an unsatisfactory systematic hypothesis of one paraphyletic and three polyphyletic traditional species. The estimated divergence times place the origin of the genus in the early Miocene (c. 22 Ma) and the divergence of most currently recognized species in the middle to late Miocene. The inferred ancestral distribution suggests that the genus and most of its species originated somewhere in Arabia or the Middle East, with the exception of the Mesalina olivieri complex, which may be of African origin. Main conclusions Phylogenetic reconstruction based on the three loci studied suggests a higher than expected cryptic diversity of Mesalina in North Africa and the Middle East. We suggest that the tectonic movements of the Arabian plate, coupled with the climatic changes occurring since the Miocene, may be responsible for the phylogeographical patterns of North African and Middle Eastern Mesalina.

Setting up effective conservation strategies requires the precise determination of the targeted species’ distribution area and, if possible, its local abundance. However, detection issues make these objectives complex for most vertebrates. The detection probability is usually

The purpose of this application, under Article 75.6 of the Code, is to conserve the usage of the specific name of Stenodactylus sthenodactylus (Lichtenstein, 1823) for a species of gecko from North Africa by designating a neotype to replace the lectotype. Prevailing usage of the name is threatened by the identity of the lectotype, which exhibits the characters of Stenodactylus mauritanicus Guichenot, 1850. It is proposed that the existing name-bearing type for the species Stenodactylus sthenodactylus (Lichtenstein, 1823) be set aside and a neotype be designated in accord with prevailing usage.

Recent molecular phylogenies of the Acanthodactylus pardalis species-group have revealed a deep genetic divergence within the nominal species A. busacki from north-west Africa. The species is phylogenetically separated into northern and southern lineages, which correspond to a previously observed morphological differentiation between the northern and southern populations of this species. Based on morphological comparisons of the type material and location of the type locality, the nomen Acanthodactylus busacki Salvador, 1982 is assigned here to the southern lineage, known from the northern Saharan Atlantic coastal desert. The northern lineage, described here as Acanthodactylus margaritae sp. nov., is prominently characterized by weakly keeled dorsal scales and a characteristic colour pattern. The new species is endemic to Morocco and confined to arid and semi-arid bioclimatic areas between the High Atlas and Anti-Atlas Mountains, from around Tamri in the north to Tiznit in the south and the Souss valley in the east.

The origin of Saharan biodiversity is poorly understood, in part because the geological and paleoclimatic events that presumably shaped species diversity are still controversial, but also because few studies have explored causal explanations for the origin of Saharan diversity using a phylogenetic framework. Here, we use mtDNA (16S and ND4 genes) and nDNA (MC1R and CMOS genes) to infer the relationships and biogeographic history of North African agamas (genus Agama). Agamas are conspicuous, diverse and abundant African lizards that also occur in the Saharan xeric and mesic environments. Our results revealed the presence of three Agama lineages in North Africa: one Afrotropical, one Sahelo-Saharan, and one broadly distributed in North Africa and mainly Saharan. Southern Mauritania contains the highest known diversity, with all three lineages present. Results suggest that agamas colonized the Sahara twice, but only one lineage was able to radiate and diversify there. Species in the Saharan lineage are mostly allopatric, and their splitting, genetic diversity and distribution are greatly explained by mountain ranges. One species in this lineage has colonized the Mediterranean climatic zone (A. impalearis), and another one the Sahel savannah (A. boueti). The other lineage to colonize the Sahara corresponds to A. boulengeri, an eminently Sahelian species that also inhabits Saharan mountain ranges in Mauritania and Mali. Phylogenetic analyses indicate that allopatric montane populations within some currently recognized species are also genetically divergent. Our study therefore concludes that vicariant speciation is a leading motor of species diversification in the area: Inside the Sahara, associated to mountain-ranges isolated by dune seas and bare plains; outside, associated to less harsh climates to the North and South. Paleoclimatic oscillations are suggested as causal explanations of the vicariant distribution and origin of species. Agamas are thought to have colonized northern Africa during wet periods, with subsequent dry periods fragmenting species distribution and leading to allopatric populations associated to milder and wetter climates in the Mediterranean, Sahel, and in Saharan mountains, in an island-model fashion. Finally, our results support the synonymization of A. castroviejoi with A. boueti, the reciprocal monophyly of all other North African agamas, and suggest one candidate species within A. boulengeri.

Research was supported by grants from Fundacao para a Ciencia e Tecnologia (FCT): SFRH/BD/25012/2005 (to R.V.), SFRH/BPD/26546/2006 (to A.P.), PTDC/BIA-BDE/74288/2006 (to D.J.H.) and PTDC/BIA-BEC/105327/2008 (to A.P.); from the Ministerio de Educacion y Ciencia, Spain: CGL2009-11663/BOS, Grup de Recerca Emergent of the Generalitat de Catalunya: 2009SGR1462; and an Intramural Grant from the Consejo Superior de Investigaciones Cientificas, Spain: 2008301031 (to S.C.).

The Common Wall Lizard (Podarcis muralis) has been introduced within large parts of Central Europe, the UK and parts of North America. In an introduced population of this species in Lower Saxony, Germany, we found in addition to mtDNA haplotypes ofP. muralisalso haplotypes of its congenerPodarcis liolepis, a species that hitherto has never been recorded outside its native range. We therefore, (1) wanted to identify the geographic origin of the founder individuals of both non-native populations, (2) test for hybridization between introduced individuals of both species in Germany and (3) compare levels of genetic diversity between native and introduced populations. We sequenced a fragment of the mitochondrial cytochromebgene and genotyped individuals of the introduced as well as native populations of both species at eleven microsatellite loci. Our results suggest that the founders presumably stem from a region in the eastern Pyrenees, where sympatric populations ofP. muralisandP. liolepisare known. No evidence for gene flow between the two species was found in the introduced population. These results are consistent with behavioural observations indicating agonistic interactions ofP. muralistowardsP. liolepisrather than cross-species attraction. Compared to the native populations, high levels of genetic diversity have been retained in the introduced population of both species and no evidence for a genetic bottleneck was found. The effective population size was high inP. muralis, but substantially smaller inP. liolepis.