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Dietary studies are essential to unravel the functioning of ecosystems and ultimately to understand biodiversity. This task, which at first may seem simple, becomes especially complex in those cases of omnivorous species with highly variable diets. In this regard, the emergence of next-generation DNA sequencing methodologies represents a powerful tool to address the problem. Here we implement a high-throughput metabarcoding strategy based on the analysis of four molecular markers aimed at sequencing both mitochondrial (animal prey) and chloroplast (diet plants) genome fragments from fecal samples of two lizard species endemic to the Balearic Archipelago (Podarcis lilfordi and P. pityusensis) obtained through non-invasive methods. The results allowed for the characterization of their diets with a high degree of taxonomic detail and have contributed a large number of new trophic records. The reported diets are based mainly on the consumption of arthropods, mollusks and plants from a diversity of taxonomic orders, as well as carrion and marine subsidies. Our analyses also reveal inter- and intra-specific differences both in terms of seasonality and geographical distribution of the sampled lizard populations. These molecular findings provide new insights into the trophic interactions of these threatened endemic lizards in their unique and isolated ecosystems.

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Gut microbial communities provide essential functions to their hosts and are known to influence both their ecology and evolution. However, our knowledge of these complex associations is still very limited in reptiles. Here we report the 16S rRNA gene faecal microbiota profiles of two lizard species endemic to the Balearic archipelago (Podarcis lilfordi and P. pityusensis), encompassing their allopatric range of distribution through a noninvasive sampling, as an alternative to previ- ous studies that implied killing specimens of these IUCN endangered and near-threatened species, respectively. Both lizard species showed a faecal microbiome composition consistent with their omnivorous trophic ecology, with a high representa- tion of cellulolytic bacteria taxa. We also identified species-specific core microbiota signatures and retrieved lizard species, islet ascription, and seasonality as the main factors in explaining bacterial community composition. The different Balearic Podarcis populations are characterised by harbouring a high proportion of unique bacterial taxa, thus reinforcing their view as unique and divergent evolutionary entities.

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This is our fourth report in a series on our whereabouts while collecting data for a future revision of the present subspecific order of the endemic Balearic sisterspecies Podarcis lilfordi (GÜNTHER, 1874) and Podarcis pityusensis (BOSCÁ, 1883), which data are stored in our free accessible database at www.pityusensis.nl (VAN DEN BERG & ZAWADZKI 2011 ; VAN DEN BERG et al. 2013 ; VAN DEN BERG et al. 2014). During this trip from the 22nd of May untill the 6th of June 2014, we were able to collect data on various mainland Ibiza locations, as well as the following adjacent islands; Tagomago, Dau Gran, Negra Llevant, Bosc de Conillera, Conillera, Espartar, S’Espardell de S’Espartar, and Escui de S’Espartar. We also visited Escui de Cala d’Hort, and can confirm this rock is without lizards. We also introduce a simplified representation of the ventral coloration as a possible determining key.

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The association between polymorphism at the mc1r locus and colour variation was studied in two wall lizard species (Podarcis lilfordi and P. pityusensis) from the Balearic archipelago. Podarcis lilfordi comprises several deep mitochondrial lineages, the oldest of which originated in the Pliocene, while much shallower mitochondrial lineages are found in P. pityusensis. Here, we examined whether specific substitutions were associated with the melanic colouration found in islet populations of these species. Homologous nuclear sequences covering most of the mc1r gene were obtained from 73 individuals from melanic and non-melanic Podarcis from different populations (the entire gene was also sequenced in six selected individuals). MtDNA gene trees were also constructed and used as a framework to assess mc1r diversity. Mc1r showed greater polymorphism in P. lilfordi than in P. pityusensis. However, we observed no substitutions that were common to all melanic individuals across the two species. Only one significant association was detected in the mc1r partial sequence, but this was a synonymous A/G mutation with A alleles being more abundant in melanic populations. In addition, there were no associations between the main dominant phenotypes (green and brown, blue and yellow spots and ventral colour) and synonymous or non-synonymous substitutions in the mc1r gene. There was no statistical evidence of selection on mc1r. This study suggests no relationship between mc1r polymorphism and colour variation in Balearic Podarcis.

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EL ESTUDIO ABORDADO EN LA TESIS VERSA SOBRE LA CARACTERIZACION TAXONOMICA DE LA LAGARTIJA DE LAS PITIUSAS PODARCIS PITVUSENSIS. SE ANALIZAN LAS DISTINTAS POBLACIONES DESDE TRES ASPECTOS DISTINTOS: EL ANALISISBIOMETRICO EL ANALISIS ELECTROFORETICO DE DISTINTAS PROTEINAS Y EL ANALISIS COLORIMETRICO. LOS ANALISIS ESTADISTICOS APLICADOS SOBRE LAS VARIANTES BIOMETRICAS DEMUESTRAN LA EXISTENCIA DE DIVERSOS GRUPOS DE POBLACIONES MUY SEMEJANTES ENTRE SI. LA VARIABILIDAD DE LA ESPECIE NO SOLO ES FENOTIPICA SINO QUE TAMBIEN ES GENETICA DETECTANDOSE UNA DIVERSIDAD EN ESTOS CARACTERES SUPERIOR A LA ESPERADA EN REPTILES. SE OBSERVA UNA ALTA HETEROSIS QUE ES CARACTERISTICA DE LA ESPECIE LO QUE PARECE DEMOSTRAR QUE ESTA SE ENCUENTRA EN LAS PRIMERAS FASES DE COLONIZACIONY ADAPTACION A LOS DIFERENTES HABITATS OFRECEN LAS ISLAS QUE OCUPA. SE CONSTATA LA ACCION DEL EFECTO FUNDADOR Y LA DERIVA GENETICA EN LOS TRES ASPECTOS CONSIDERADOS EN LA TESIS ASI COMO UNA TENDENCIA EVOLUTIVA HACIA EL AUMENTO DE TAMAÑO SIEMPRE QUE NO EXISTA UNA PRESION SELECTIVA CONTRARIA. SUCEDE LO MISMO CON EL MELANISMO. CONSIDERANDO EL ESTADO EVOLUTIVO ACTUAL DE LA ESPECIE REFLEJADO EN LA PLASTICIDAD DE LAS DISTINTAS POBLACIONES DE ESTALAARTIJA Y EN LA ADAPTACION QUE MANIFIESTAN EN CADA NICHO CONCRETO ASI COMO EL CONCEPTO RESTRICTIVO ACTUAL DE SUBESPECIE LA AUTORA CONSIDERA QUE SOLO PUEDEN CONSIDERARSE SEIS TAXONES SUBESPECIFICOS O SUBESPECIES DE LA LAGARTIJA DE LAS PITIUSAS.

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In this paper are presented the results obtained with 45 populations of Podarcis pityusensis. Several multivariant technics are performed: discriminant analysis, cluster analysis and canonic analysis of populations. These populations present gradual change in all their biometric characteristics, and also a great interpopulation variability, that invalidate th statistical methods to discriminate between all of them. In different analysis very related population groups are found, that suggests they are constitute the same subspecies, in the actual taxonomic sense. These groups always inhabits islands with the same geological age, it is therefore necessary to complete the study with othr biological reflections, all of which are getting ready.

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The variation in morphological and colouring features shown by the insular lacertid populations of Podarcis pityusensis is discussed from the point of view of their adaptive advantages to specific insular ecosystems. Insularity factors, i.e. area and island-age, have been found to be related to average body size, and the average luminosity of each population. Populations tend to show a size increase, a greater morphological homogeneity and darker dorsal colouring on smaller and older islands. Genetic drift seems to play a secondary role, whereas a positive selection in favour of melanism and giantism is observed. Both features are not linked as cause and effect, but seem to share a common cause: isolation and time enough to allow selection to take place. Predation, though slight in degree, does exist, and seems to be one of the selective pressure favouring melanism, together with the parallel trend towards an increase in body size and the need to an effective thermoregulation during the early hours of the day.

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The Ibiza wall lizard is the symbol of the Pityusic-Archipelago, but what makes this colorful reptile so special? The Symbol: wall lizards of Ibiza and Formentera will take you on a journey into the culture, biology, ecology, and conservation of Ibiza and Formentera’s most iconic animal.

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We provide a fi rst complete list of the present and lost reptile type material of the Zoologische Staatssammlung München (ZSM) and discuss various problems involved. The collection currently houses primary types of 184 taxa (128 holotypes, 44 lectotypes, and 12 taxa based on syntype series), 112 of them currently considered valid. Furthermore, 63 taxa are exclusively represented by secondary types (paratypes, paralectotypes). The ZSM collection strongly suffered from losses during World War II. Approximately 90 primary reptile type specimens or primary type series are considered to be destroyed during that time. The historical focus of the collection is the South American region. This is primarily based on material collected by Spix and Martius during their expedition to Brazil from 1817 to 1820. Primary types of 83 reptile taxa were collected during this expedition – approximately half of them described by J. G. Wagler – but currently specimens of only 53 taxa are still present in Munich. Subsequently, herpetological research in South America was continued during the fi rst half of the 20th Century by L. Müller und W. Hellmich, who deposited primary type material of 95 reptile taxa (49 from South America, among them 26 of the iguanid genus Liolaemus) in the ZSM, 47 of them still represented by primary types. Another geographical focus of the reptile type collection is the Mediterranean area, the Macaronesian region and the Middle East with a total of 46 extant primary types. Herpetological research in this area dates back to descriptions by G. Jan in 1863 and was continued by L. Müller, H. H. Schleich, A. Beutler, and especially J. F. Schmidtler and their respective collaborators.

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The population of Illiot de Sa Mesquida: Podarcis pityusensis characae (Buchholz 1954) is regarded as a synonym of Podarcis pityusensis pityusensis (Boscá 1883).

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The status of the populations of Podarcis pityusensis on about 70 islets and small islands around Ibiza and Formentera (Balearic Islands) is examined, using data from our own observations, and, to a lesser amount, other publications. Lizard populations were found on 43 islets, but data are lacking for another 13. Only 10 sites (18 %) have abundant and well-maintained populations. In 13 localities (23%), there is no geographic isolation between the populations, or this isolation is very poor and incomplete. The high probability of populations mixing, or actual observation of this mixing, in 19 islands (34%) is indicated. Human pressure on lizard populations is strong in 14 cases (25 %). And finally, 18 populations (about one third) may be considered highly endangered or already extinct by elimination or genetic mixing with other populations. Among the subspecies which became extinct through mixing are P.p. miguelensis, P.p. subformenterae, P.p. algae, P.p. sabinae and P.p. grueni. The need for adequate protective measures aimed at the conservation of the remaining populations is emphasized.

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The Ibizan wall lizard, Podarcis pityusensis, was the subject of several documented translocations by the German vertebrate zoologist Martin Eisentraut, in 1930. He aimed to initiate long-term experiments into the evolution of melanism and other morphological traits and accordingly he designed introductions into five islets that (he believed) contained no lizards. In this study, we analyzed the genetic and morphological characteristics of individuals we found there. We found no lizards on two of the islets, namely Escull de Tramuntana and Galera, but for the first time, detected a large population on a third islet, Es Vaixell. Eisentraut founded the Es Vaixell population with nonmelanistic Ibizan specimens, but the present day population of Es Vaixell was found to be fully melanistic. Genetic markers support a strong similarity between Es Vaixell and its neighbour islet, Na Gorra, and indicate that, in all likelihood, the individuals introduced by Eisentraut have left no descendants. It is likely that Es Vaixell already contained lizards prior to this introduction. Analyses of microsatellite DNA placed individuals from a fourth islet, Dau Gran, with those of one of its source islet, Escull Vermell. They are also morphologically close to individuals from Escull Vermell. This suggests that selection pressures could have favoured the Escull Vermell phenotype following introduction. For reasons we discuss, the translocations have revealed less than Eisentraut would have originally hoped for. Although evolutionary processes are normally time-consuming, these translocations do provide some potential insights into the rapid evolution of lizard morphology following colonization.

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Two monophyletic sister species of wall lizards inhabit the two main groups of Balearic Islands: Podarcis lilfordi from islets and small islands around Mallorca and Menorca and Podarcis pityusensis from Ibiza, Formentera and associated islets. Genetic diversity within the endangered P. lilfordi has been well characterized, but P. pityusensis has not been studied in depth. Here, 2430 bp of mtDNA and 15 microsatellite loci were analysed from P. pityusensis populations from across its natural range. Two main genetic groupings were identified, although geographical structuring differed slightly between the mtDNA and the nuclear loci. In general, individuals from islets/islands adjacent to the main island of Ibiza were genetically distinct from those from Formentera and the associated Freus islands for both mtDNA and the nuclear loci. However, most individuals from the island of Ibiza were grouped with neighbouring islets/islands for nuclear loci, but with Formentera and Freus islands for the mitochondrial locus. A time-calibrated Bayesian tree was constructed for the principal mitochondrial lineages within the Balearics, using the multispecies coalescent model, and provided statistical support for divergence of the two main P. pityusensis lineages 0.111–0.295 Ma. This suggests a mid-late Pleistocene intraspecific divergence, compared with an early Pleistocene divergence in P. lilfordi, and postdates some major increases in sea level between 0.4 and 0.6 Ma, which may have flooded Formentera. The program IMa2 provided a posterior divergence time of 0.089–0.221 Ma, which was similar to the multispecies coalescent tree estimate. More significantly, it indicated low but asymmetric effective gene copy migration rates, with higher migration from Formentera to Ibiza populations. Our findings suggest that much of the present-day diversity may have originated from a late Pleistocene colonization of one island group from the other, followed by allopatric divergence of these populations. Subsequent gene flow between these insular groups seems likely to be explained by recent human introductions. Two evolutionary significant units can be defined for P. pityusensis but these units would need to exclude the populations that have been the subjects of recent admixture.

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The alteration of a habitat such as that caused by the introduction of exotic animal species that displace the native ones, reducing their populations or leading them to extinction, can result in the disruption of species interactions which may have evolved during millions of years. The insular ecosystems are especially vulnerable to such disturbances, as they are usually less complex and have a lower number of species than the continental ones. In the present work I document the consequences of the disruption of plant-disperser interactions, caused by the introduction of carnivorous mammals in the Balearic Islands, for the populations of two shrub species: Cneorum tricoccon L., with a distribution restricted to the western Mediterranean, and Daphne rodriguezii Texidor, endemic from Menorca island. Whereas carnivores have replaced ⁄ the native dispersers (lizards) of the former, notably modifying its distribution -especially in Mallorca-, the plant-lizard mutualism disruption seems to have been dramatic for the second species, drastically reducing its populations except in an islet where lizards still persist.