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of the real lizards, family Lacertidae
Podarcis lilfordi - Illot d’en Mel ESU (TRIAY, 1998)
Berg, M.P. van den (2011) -
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.
Berg, M.P. van den (2015) -
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.
Berg, M.P. van den & Zawadzki, M. (2011) -
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.
Berg, M.P. van den & Zawadzki, M. & Kroniger, M. (2013) -
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.
Brown, R.P. & Terrasa, B. & Pérez-Mellado, V. & Castro, J.A. & Hoskisson, P.A. & Picornell, A. & Ramon, M.M. (2008) -
Phylogenetic relationships and timings of major cladogenesis events are investigated in the Balearic Island lizards Podarcis lilfordi and Podarcis pityusensis using 2675 bp of mitochondrial and nuclear DNA sequences. Partitioned Bayesian and Maximum Parsimony analyses provided a well-resolved phylogeny with high node-support values. Bayesian MCMC estimation of node dates was investigated by comparing means of posterior distributions from different subsets of the sequence against the most robust analysis which used multiple partitions and allowed for rate heterogeneity among branches under a rate-drift model. Evolutionary rates were systematically underestimated and thus divergence times overestimated when sequences containing lower numbers of variable sites were used (based on ingroup node constraints). The following analyses allowed the best recovery of node times under the constant-rate (i.e., perfect clock) model: (i) all cytochrome b sequence (partitioned by codon position), (ii) cytochrome b (codon position 3 alone), (iii) NADH dehydrogenase (subunits 1 and 2; partitioned by codon position), (iv) cytochrome b and NADH dehydrogenase sequence together (six gene–codon partitions), (v) all unpartitioned sequence, (vi) a full multipartition analysis (nine partitions). Of these, only (iv) and (vi) performed well under the rate-drift model. These findings have significant implications for dating of recent divergence times in other taxa. The earliest P. lilfordi cladogenesis event (divergence of Menorcan populations), occurred before the end of the Pliocene, some 2.6 Ma. Subsequent events led to a West Mallorcan lineage (2.0 Ma ago), followed 1.2 Ma ago by divergence of populations from the southern part of the Cabrera archipelago from a widely-distributed group from north Cabrera, northern and southern Mallorcan islets. Divergence within P. pityusensis is more recent with the main Ibiza and Formentera clades sharing a common ancestor at about 1.0 Ma ago. Climatic and sea level changes are likely to have initiated cladogenesis, with lineages making secondary contact during periodic landbridge formation. This oscillating cross-archipelago pattern in which ancient divergence is followed by repeated contact resembles that seen between East-West refugia populations from mainland Europe.
C.B.C.,S.L. (2003) -
Pérez-Cembranos, A. & Pérez-Mellado, V. (2016) -
Pérez-Cembranos, A. & Pérez-Mellado, V. & Alemany, I. & Bassitta, M. & Terrasa, B. & Picornell, A. & Castro, J.A. & Brown, R.P. & Ramon, C. (2020) -
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.
Pérez-Mellado, V. (1998) -
Pérez-Mellado, V. (2004) -
Pérez-Mellado, V. & Hernández-Estévez,J.A. & Garcia-Diaz, T. & Terrasa, B. & Ramón, M.M. & Castro, J. & Picornell, A. & Martin-Vallejo, J. & Brown, R. (2008) -
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.
Pretus, J.L. & Massana, M. (2012) -
We have assessed the isotopic signatures of C, N and S from sprouts, flowers and fruits of the dominant plants of the Mel islet, of their most abundant arthropods and of the endemic lizard Podarcis lilfordi, to produce a diagram of proximities between taxa allowing some inferences on the trophic dependence of this latter species. Despite the difficulties arisen from the spatial heterogeneity of the isotopic basal values, the close proximity of the lizard to certain arthropods suggests a selective animal diet and, in general, a reduced degree of omnivory, and do not support any suspicion of a lowered trophic level from insectivorous to vegetarian style due to restrictions of island life.
Pretus, J.L. & Marquès, R. & Pérez-Mellado, V. (2004) -
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.
Salvador, A. (2006) -
Salvador, A. (2009) -
Salvador, A. (2015) -
Terrasa, B. & Pérez-Mellado, V. & Brown, R.P. & Picornell, A. & Castro, A. & Ramon, M.M. (2009) -
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.
Triay, R. (1998) -
Universitat de Barcelona (2007) -
Viada Sauleda, C. (2021) -
Zawadzki, M. & Berg, M.P. van den (2011) -
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.