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of the real lizards, family Lacertidae
Podarcis lilfordi - Illa de ses Bledes ESU (SALVADOR, 1985)
Barbadillo, L.J. (1987) -
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.
C.B.C.,S.L. (2003) -
Hornero, M.J. & Roca, V. (1992) -
A survey about the helminthfauna of Podarcis lilfordi (Günther, 1874) (Sauria, Lacertidae) in the Gimnesic Islands (Balearic Islands, Spain) has been carried out. Eleven species of helminths were found, two Digenea, eight Nematoda and one Acanthocephala. Data of prevalence of each helminth species are indicated. The nematodes Skrjabinodon medinae and Spauligodon cabrerae show the highest values of prevalence and abundance. Host-parasite relationships are discussed, and the absence of cestodes is pointed out.
Mayol, J. (1997) -
Mayol, J. (2004) -
Available data regarding conservation status of lizard populations from Balearic Islands, as well as threat factors affecting them are presented. Some populations are highly threatened, due to their intrinsic limitation of island surface occupied and, in addition, there are cases of viable artificial populations. Hence, we propose the translocation of most threatened populations to islets today unoccupied by lizards. We show the critria under which such operation could be performed.
Pérez-Cembranos, A. & Pérez-Mellado, V. (2016) -
Pérez-Mellado, V. (1997) -
Pérez-Mellado, V. (1998) -
Pérez-Mellado, V. (2005) -
Pérez-Mellado, V. & Corti, C. (1993) -
We examined the diets of several species of Podarcis from different western Mediterranean islands. We tested the prediction of more generalized diets in lizards from poor environments. We also examined the extert and mode of herbivory in relation to arthropod diversity in the diet. Lizards from the Tuscan Archipelago, P. sicula from Menorca, and P. tiliguerta from Corsica all show a rather generalized diet. In contrast, P. lilfordi and P. pilyusensis from the Balearic Islands and, to a lesser extent, P. hispanica from Benidorm Island, appear much more stenophagous, including a high proportion of clumped prey in their diets. Plant matter is a common food item in most of the population studied, specially in Balearic lizards. A marked seasonal shift in the degree of herbivory was observed in these species where high-energy plant parts are frequently consumed during summer. In one of the Balearic Islands (Nitge), the bulk of the summer diet was formed by pollen and nectar of one particular plant species. Herbivory, consumption of clumped prey and other dietary peculiarities of insular populations of Mediterranean lizards indicate a very flexible feeding behaviour compared to mainland congenerics. This could result from a lack of predation pressure allowing high population densities to be reached in islets with poor trophic resources. Differences found in dietary characteristics among island populations can be interpreted as a consequence of different current ecological conditions, as well as historical and biogeographical differences among the islands.
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. & Pérez-Cembranos, A. & Garrido, M. & Luiselli, L. & Corti, C. (2011) -
While the use of faecal pellets is widely accepted as a primary methodological source of data for dietary studies, a recent paper advocated for the use of gut contents. This was due to the fact that faecal samples would give biased results of the diet of arthropod predators, due to a lower representation of soft-bodied prey in faecal pellets. To test this assumption, we compared the spring diet of several populations of two insular lizards from the Balearic Islands (Spain), Podarcis lilfordi and Podarcis pityusensis, using both faecal pellets and gut contents. Our results do not support the supposed bias of dietary analyses based on faecal pellets. Indeed, soft-bodied prey and particularly insect larvae are often equally represented in faecal pellets and gut contents. Alternatively, soft bodied prey are represented in different proportions in gut contents and faecal pellets, but in some cases with higher proportions being observed in the gut contents, and in other cases with higher proportions in faecal samples. We conclude that faecal pellets can be a reliable source of information for dietary studies.
Pérez-Mellado, V. & Salvador, A. (1988) -
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.
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.
Ramón, M. & Castro, J.A. (1988) -
The Balearic lizard P. lilfordi inhabits the Gymnesies Islands and have sexual dimorphism. By means of biometric studies and analyses such as the discriminant analysis, it has been determined the morphometric characters that determine this sexual dimorphism. The characters chosen by the analysis were: body length, pileus width, number of gular scales, length of the four finger of the posterior leg. The differential measures of these characters makes the males to have a burlness and robustness greater than the females of the same population. Nevertheless, it cannot be said that in all P. lilfordi populations, the males will be aways the most burliness and robustness,but this will depend upon th population of P. lilfordi we take into consideration.
Roca, V. & Hornero, M.J. (1994) -
A survey of the helminth communities of Podarcis pityusensis (Bosca, 1883) and Podarcis lilfordi (Gunther, 1874) (Sauria: Lacertidae) from the Pityusic and Gimnesic islands, respectively, in the Balearic Islands, Spain, was conducted. Both host species harbour similar though not identical helminth infracommunities. An analysis of the patterns of diversity for all helminths revealed that both lizards have depauperate isolationist infracommunities, possibly as a result of factors such as host ectothermy, the simplicity of their digestive canal, low vagility, and generalist feeding.
Salvador, A. (1985) -
Salvador, A. (1986) -
Salvador, A. (2006) -
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) -