Mertens, R. (1952) - Description of Podarcis raffonei raffonei. - In: “Neue Eidechsenrassen von den Liparischen Inseln”. Senckenbergiana, Frankfurt/Main, 32: 309-314. Capula, M. (1994) - Genetic variation and differentiation in the lizard, Podarcis wagleriana (Reptilia: Lacertidae). - Biological Journal of the Linnean Society, 52 (2): 177-196. × The electrophoretic variation at 26 presumptive gene loci was investigated in populations of Podarcis ivagleriana from Sicily, the Aegadian Islands, and the Aeolian Islands. For interspecific comparison, samples of the closely related lizard P. sicula from the same geographic area were also used. Population heterogeneity analyses carried out by the estimation of F-statistics and Nei`s standard genetic distance, showed a high genetic homogeneity within P. sicula, but a noticeable genetic differentiation within P. wagleriana. In the latter species, Nei`s D ranged from 0 to 0.212, and this is because the Aeolian populations were quite distinct from those inhabiting Sicily and the Aegadian Islands. Fixed differences identified at three loci (Ck, Ada, Gp-4) contributed to a relatively high value of Nei`s standard genetic distance between the two population groups (D= 0.147). This value is very similar to those found comparing pairs of well-recognized biological species included in the genera Podarcis and Lacerta. Estimation of the time of evolutionary divergence shows that the Aeolian and Sicilian populations of P. wagleriana have been isolated geographically for a long time (0.7 Myr according to Nei`s formula; 2 Myr according to Sarich`s calibration), indicating evolutionary divergence at the species level. Based on genetic and biogeographic data, it is suggested the recognition of full specific status for the Aeolian populations, for which the name P. rajfonei comb. nova (Aeolian wall lizard) is proposed. Electrophoretic data and comparative species distributions suggest that (1) Podarcis sicula recently colonized the Aeolian Islands, and (2) it has competed successfully with P. rajfonei in this area, greatly reducing the range of the latter and causing the extinction of most of its populations. In fact, P. sicula is widespread in the Aeolian Archipelago, while P. rajfonei is confined at present to one large island (Vulcano) and three tiny islands (Strombolicchio, Scoglio Faraglione, La Canna). This can be considered a classic example of competitive exclusion of a native form (P. rajfonei) by a species accidentally introduced by man (P. sicula). Capula, M. (2004) - Low genetic variation in a critically endangered Mediterranean lizard: conservation concerns for Podarcis raffonei (Reptilia, Lacertidae). - Italian Journal of Zoology, 71, Supplement 1: 161-166. × The conservation status of Podarcis raffonei, native to the Aeolian Islands (north cast of Sicily, Tyrrhenian Sea), is assessed by studying its genetic structure and evidencing factors affecting the survival of the species. Genetic variation in the species is quite low and genetic subdivision is high, as compared to other lacertid lizards and to vertebrates in general. Very little gene flow was detected, implying little or no contact between populations. The four remaining populations of P. raffonei are under severe threat from the effects of habitat alteration, interspecific competition, collecting and trade, very low population density and inbreeding, population fragmentation, and apparent loss of genetic variation. Possible management and conservation measures are suggested. Capula, M. (2006) - Population heterogeneity and conservation of the Aeolian wall lizard, Podarcis raffonei. - In: Corti, C., Cascio, P.L. & M. Biaggini (eds): Mainland and insular lacertid lizards: a mediterranean perspective. – Firenze University Press, Firenze. 24-32. × The conservation status of Podarcis raffonei, native to the Aeolian Islands (north-east of Sicily, Tyrrhenian Sea), is assessed anaslyzing in genetic structure and evidencing factors affecting the survival of the species. Genetiv variation in the species is quite low and genetic subdivision is high, as compared to other lacertid lizards. The four remaining populations of P. raffonei are under severe threat from the effects of habitat alteration, interspecific competition, collecting and trade, very low population density and inbreeding, population fragmentation, and apparent loss of genetic variation. Possible management and conservation measures are suggested.
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