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of the real lizards, family Lacertidae
Podarcis lilfordi - Illa Na Redona ESU (SALVADOR, 1979)
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.
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) -
Castilla, M.A. (1999) -
his study examines whether the lizard Podarcis lilfordi is a legitimate disperser of the rare Mediterranean plant Withania frutescens by using the biochemical test of triphenyl-2H-tetrazolium chloride for testing seed viability. This lizard eats the fresh fruits of the plants and defecates intact seeds which have been retained 1 to 3 d in their gut. Viability of seeds recovered from faeces was very high and comparable to the viability of fresh seeds. Seed dispersal by this lizard in the Balearic islands may facilitate population expansion of this rare plant in the Balearics.
Larrucea, J.R. & Ballesteros, E. & Ginés Grecia, Á. & McMinn Grivé, M. & Pérez Mellado, V. (2016) -
Mayol Serra, J. (1985) -
Mayol, J. (1997) -
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. (1997) -
Pérez-Mellado, V. (1998) -
Pérez-Mellado, V. (2004) -
Pérez-Mellado, V. (2005) -
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.
Pérez-Mellado, V. & Traveset, A. (1998) -
Pérez-Mellado, V. & Traveset, A. (1999) -
Different kinds of interactions between lizards and plants in the Mediterranean basin have been described. Lizards have shown to `use` plants as a refuge against predators, as a foraging site, as a thermal microhabitat or as a food resource. In the last case, they can either act as herbivores (+/- interaction, consuming vegetative and/or reproductive parts, and damaging the plant to a higher or lower degree) or as mutualists (+/+ interaction, by behaving as legitimate pollinators and/or seed dispersers). The importance of plants as a food resource for Mediterranean lizards has been found to be high in insular habitats, espescially in small islands, where the paucity of arthropod prey availability redirects the foraging activity of lizards towards other nutrient resources. In such small islands, plants may play a major role in the trophic ecology of lacertid lizards, as suggested by recent studies. Likewise, lizards may be important both as efficient pollen transporters and seed dispersersfor a variety of plants. Some of these lizard-plant interactions are unique. The effect lizards have on the reproductive and dispersal succes of some species may be very relevant for plant preserveation, and in turn, the preserveation of prticular behavioral and ecological traits of the particular lizard populations depends, at least partly, on the plants they interact with.
Pons, G. & Palmer, M. (1996) -
Roca, V. (1993) -
A Survey about helminthfauna of the Saurians living in Cabrera archipelago, Tarentola mauritanica, Hemidactylus turcicus and Podarcis lilfordi, has been made. Sixteen species of helminths have been found from these hosts: 1 trematode (Paradistomum mutabile), 5 cestodes (Oochoristica gallica, Nematotaenia tarentolae, Diplopylidium acanthotetra larvae, Diplopylidium nolleri larvae, Joyeuxiella pasqualei larvae), 9 nematodes (Skrjabinodon medinae, Skrjabinodon mascomai, Spauligodon paratectipenis, Spauligodon sp., Spauligodon cabrerae, Parapharyngodon bulbosus, Parapharyngodon micipsae, Acuaria sp. larvae, Spirurida gen. sp. larvae) and 1 acanthocephalan (Centrorhynchus sp. larvae). The taxonomy and autoecology of the helminths is studied and the structures of helminth communities are analized. This analysis shows that helminth communities of the Saurians of Cabrera are depauperate, tipically isolationist and conditioned by several biotic characteristics of the hosts.
Salvador, A. (1979) -
Salvador, A. (1985) -
Salvador, A. (1986) -
Salvador, A. (1993) -
Salvador, A. (2006) -
Salvador, A. (2009) -
Salvador, A. (2015) -
Salvador, A. & Pleguezuelos, J.M. (2002) -
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.
Viada Sauleda, C. (2021) -