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In this article an introduction is given on the geological history leading to the separation of Podarcis lilfordi (GÜNTHER, 1874) and Podarcis pityusensis (BOSCÁ, 1883) as separate species, as well as a Holocene sea level rise model which combined with bathymetric data leads to an estimation of recent divergence time in populations of the Balearic lizards.

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New data on estimated divergence times of the populations of lacertid lizards in the Balearic Islands are provided in this second update of the October 2011 article: Estimating recent divergence time in populations of Podarcis lilfordi (GÜNTHER, 1874) and Podarcis pityusensis (BOSCÁ, 1883) (VAN DEN BERG 2011), which received its first update May 2012. In most cases better estimations of divergence times were available by using the NAVIONICS SonarCharts™webapp.

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It is reported about the rediscovery of a population of the Balearic Lizard (Podarcis lilfordi) on the Illa de Ses Mones in the harbour of Port d´Addaia. This population has been considered to have become extinct during the 1990s due to the introduction of the Italian Wall Lizard (Podarcis siculus). Descriptions of the island and the lizards are given and for the first time it is reported about the sympatric occurrence of Podarcis lilfordi and P. siculus. Because in quite a lot of publications the nearby Illot d´en Carbó has been confused with the Illa de Ses Mones the taxonomic status of the rediscovered Podarcis lilfordi population from the Illa de Ses Mones is discussed in this paper.

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We report on our observations on Podarcis lilfordi (GÜNTHER, 1874) during our 8 day trip to the natural park of s’Albufera des Grau (Spain/Menorca) and give preliminary conclusions on the status of some populations.

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We report on our observations on Podarcis lilfordi (GÜNTHER, 1874) and other Menorcan herpetofauna during our 12 day trip to Menorca (Balearics, Spain). 13 populations of Podarcis lilfordi were surveyed, 101 specimens were measured and photographed in detail, from which 84 specimens were “buccal-swabbed” for DNA samples. The subspecific status of Hemidactylus turcicus spinalis from Addaia Gran is discussed and rejected.

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Aims: To characterize the genetic and morphological diversification of the endan- gered Balearic lizard Podarcis lilfordi and to assess the relevance of this diversity, and how it is described, to conservation measures. Location: This study covers all the populations of the Balearic lizard, Podarcis lilfordi, present in its range of distribution at coastal islets of Menorca, Mallorca and Cabrera Archipelago. Methods: We analysed genetic and morphological variation across the 43 known extant populations of the Balearic lizard, using mitochondrial and nuclear markers. We examined morphometric and scalation characters using, in some cases, phyloge- netically independent contrasts. We also incorporated the study of dorsal coloration and dorsal colour pattern including the analysis of melanism in several populations. Results: We detected clear genetic divergence between Menorcan populations and populations from Mallorca and Cabrera, in both nuclear and mtDNA markers, but genetic divergence is relatively low among different insular populations within these groups. In contrast, morphological divergence was substantial both between Menorcan and remaining populations and within these groups. Morphological traits, such as dorsal coloration, body size and the number and size of scales, seemed to be linked with differences in climatic conditions between populations. In addition, some traits, as melanism, showed a strong phylogenetic signal. Main conclusions: The morphological and genetic diversity of the Balearic lizard is incongruent with the subspecies described in the classical taxonomic literature. Moreover, current populations differ not only in some genetic and morphological features, but also in several ecological and ethological characteristics, in many cases unique to one population. Based on our results, we propose abandoning the use of subspecies to describe the extraordinary morphological diversity of the Balearic liz- ard and its replacement with the concept of evolutionary significant units (ESUs). ESUs are particularly suitable to describe and recognize such diversity and, especially, to ensure the continuity of the evolutionary process.

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The Balearic lizard, Podarcis lilfordi, is one of the key species of Menorca Biosphere Reserve. This is the only endemic terrestrial vertebrate Plio-Pleistocene, the last representative of vertebrate fauna previous to the arrival of humans. Over the past two decades since the establishment of the Biosphere Reserve, have accumulated a significant amount of knowledge on this species, both on its molecular evolution, as their demographics, characteristics of natural history, ecology, behavior and state conservation of populations Menorcan. However, some fundamental aspects of the situation of current populations are unknown and others provide amazing results from the point of view of Conservation Biology. While some traditional threats affecting the Balearic lizard seem to have disappeared or have been attenuated, new ones have emerged in recent years and old problems, which appeared to be over, have resurfaced. Human pressure on fragile populations of the Balearic lizard is manifested in many different ways and forms, as now, the main factor of uncertainty about the future of this unique species. In this paper, we review summarizes the current state of knowledge on this endemic Lacertidae, try to identify the main factors still act as threats surviving populations in coastal islets and propose some actions that would ensure the future maintenance of P. lilfordi within the Biosphere Reserve.

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he Balearic lizard, Podarcis lilfordi, is present in 43 insular populations in the Cabrera archipelago and around the coasts of Mallorca and Menorca islands (Spain). We studied lizard densities over the entire range of distribution, analyzing observed differences of density in relation to island area, habitat diversity, availability of resources, presence of predators, competitors and human disturbances. The density of the Balearic lizard varies from less than 35 to almost 8000 lizards ha-1, with an average of around 1500 lizards ha-1. In some very small islets we detected no more than 10 individuals. Using a subsample of nine coastal islets (Menorca) we did not find any significant correlation between ground arthropod biomass and lizard density. The combination of island area and its maximal altitude, its so-called biotic capacity, was also uncorrelated with lizard density. In addition, neither degree of island accessibility nor presence/absence of seagull breeding colonies, were able to explain lizard densities. Islands without ship rats (Rattus rattus) showed a significantly higher lizard density, but islands in which rat eradication programs were launched during the study period, showed lower densities than those with rats but no eradication actions. Genetic variability was significantly higher on bigger lizard populations, lacking a correlation with lizard densities. No single independent variable can explain density differences among populations under study. Our results are discussed in the light of available hypotheses on factors affecting population densities.

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A studie was carried out on 17 populations of Podarcis lilfordi inhabiting the islets off the coast of Menorca (Balearic Islands). Pattern and colouring together with the statistical analysis performed suggested that the menorcan rassenkreis comprises a total of 9 subspecies. The evolutionary processes involved appear to be fundamentally governed by the age of the islets, their distance from the coast and by their ecological conditions. Though in certain cases it may be postulated that genetic drift may have acted as a differentiating mechanism in populations which were initially small. However, interpretation of the microevolutionary processin Menorca is more difficult thnin the case of other rassenkreis of the Balearic Islands due to extinction of the `mother` population on the main island.

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A 684 bp fragment from cytochrome-b allowed a coherent arrangement of several Podarcis populations from the Balearic archipelago, in a study focused on the phylogeography of the 15 Minorcan populations of Podarcis lilfordi. A reference site with Podarcis lilfordi from Mallorca clusters with the Minorcan population, although it shares a few variations with Podarcis pityusensis that are not present in the Minorcan clade. Concerning the Minorcan islets, a two steps model is drawn accounting for the observed molecular pattern. An ancient and a derived stock of populations can be discerned, seperated by a population event replacing the former populations by the modernones on the shallowest protoislets, placing it around 7000 to 5000 BP, based on bathymetric information and Holocene sea level data. Autapomorphies are present in several sites and could be indicative of seperated demes prevailing on penninsular areas of the island, as in Cavalleria, Mola de Fornells, or even on larger regions as in the southeast Menorca. Within the framework of a vicariant model, we suggest that islet`s inhabitantshave thus retained some of the history of the now extinct mainland population.

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Aim To describe and analyse phylogeographical patterns in the endangered endemic lizard Podarcis lilfordi from across its remaining range and thereby establish baseline information on genetic diversity that will help determine conservation priorities and assist future reintroduction programs. Location Balearic Islands, Spain. Methods We analysed mitochondrial DNA (2382 bp sequence from eight genes) from 118 individuals and characterized the relationships among haplotypes using parsimony networks, as well as phylogenetic inference. Analyses of historical gene flow and population growth were used to provide further insights into population histories. Results Four unconnected parsimony networks were obtained that mirrored the main clades in the phylogenetic tree: (I) all Menorcan populations, (II) Dragonera, Malgrats and Toro islands (Western Mallorca) (III and IV) and the remaining populations from Cabrera and Mallorca. Two major haplotype groups were detected in Menorca (I) and these provided signatures of a demographic expansion and asymmetrical historical gene flow, respectively, concordant with the expected direction of colonization from south to north of the island. Populations from western Mallorca (II) showed evidence of historical allopatric fragmentation events following isolation around the start of the Pleistocene. In networks III and IV, Cabreran populations appear to have become isolated from north and south Mallorca quite recently, with asymmetric gene flow indicating a northwards dispersal direction. Main conclusions P. lilfordi is a genetically diverse species that shows substantial mtDNA structuring both between regions and, at a finer scale, between some islet populations within regions. The precarious state of some islet populations shown here to be quite divergent (e.g. Toro island in western Mallorca) means that conservation of this intraspecific biodiversity requires urgent action.

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Presentation held at the annual meeting of the AG Lacertiden in Gersfeld/Rhön the 10th of April 2011. It is reported about the rediscovery of a population of the Balearic Lizard (Podarcis lilfordi) on the Illa de Ses Mones in the harbour of Port d´Addaia. This population has been considered to have become extinct during the 1990s due to the introduction of the Italian Wall Lizard (Podarcis siculus). Descriptions of the island and the lizards are given and for the first time it is reported about the sympatric occurrence of Podarcis lilfordi and Podarcis siculus. Because in quite a lot of publications the nearby Illot d´en Carbó has been confused with the Illa de Ses Mones the taxonomic status of the rediscovered Podarcis lilfordi population from the Illa de Ses Mones and the Podarcis lilfordi carbonerae population of Illot d`en Carbó are discussed.

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As a result of their taxonomical study of the populations of the Balearic lizard of Menorca Pérez-Mellado & Salvador (1988) described three new subspecies of Podarcis lilfordi. The type series of one of them, Podarcis lilfordi carbonerae, had been collected on an island called “Isla Carbonera” in 1933. The fact that their describers could not find this islet on any map, but did not hesitate to describe these lizards as a new subspecies, was not very reasonable and surely contributed to the mystery that should surround this subspecies from now on. But it was not this fact alone that casted a bad light on this taxonomic revision, because in-depth analyses revealed more awkward mistakes. Even the rediscovery of Podarcis lilfordi carbonerae by Pérez-Mellado et al. (2002) was only based on assumptions but did not contain any scientific proof. In this paper we give new information on the possible terra typica of Podarcis lilfordi carbonerae by introducing the Illa de Ses Mones. Because neither the En Carbó nor the Ses Mones lizards can be separated from the populations of the two nearby islands Illa Gran d’Addaia and Illa Petit d’Addaia by means of coloration or meristic and metric characters, we consider Podarcis lilfordi carbonerae Pérez-Mellado & Salvador, 1988 as a synonym of Podarcis lilfordi addayae (Eisentraut, 1928).