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Sardinian populations of the snake Hemorrhois (= Coluber) hippocrepis are likely the most endangered populations of snakes in Italy. Major threats to survivorship are the anthropogenic habitat alteration and the extremely low population density, while nothing is known about the potential effects that climate change could exert on this species. The main goal of this paper is to provide helpful instruments for the short- and long-term conservation of H. hippocrepis in Sardinia. By means of an ecological modeling approach, we derived the Sardinian whip snake habitat suitability map, and we compared the potential range extent under present condition and future climatic scenarios. Results clearly show an alarming trend for H. hippocrepis conservation: changing climate conditions will cause a dramatic reduction on suitable surface since 2020, with a further collapse by 2050 (down to 11 km2). We also identified areas of species potential persistence up till 2050, where prospective management initiatives could have the greatest probability of success in this region. In particular, only one existing protected area will likely still keep suitable habitats for H. hippocrepis. Therefore, we suggest that very careful management of this relictual area should be implemented by now if we really want to save these exceedingly threatened snake populations. [ABSTRACT FROM AUTHOR]

Sardinia shows a clear lack of herpetological data due to an evident paucity of herpetological surveys. This gap of knowledge is worthy of attention, since Sardinia hosts a rich herpetofauna with a large proportion of endemic species, and distribution data are crucial for targeting conservation efforts. In this paper we provide new distribution data for Sardinian reptiles, with the aim of updating our knowledge on their specific distribution. Data were opportunistically recorded during ten years of field research in Sardinia, carried out in more than twenty campaigns from April 1999 to June 2009. All the eighteen reptile species belonging to the Sardinian fauna were recorded. A total amount of 293 faunistic data were collected from 178 different localities covering the entire study area. Within this dataset, 137 faunistic data fall outside known species' ranges as reported in the Atlas of Italian amphibians and reptiles. In conclusion, data presented here produced a remarkable increase of knowledge on Sardinian reptiles' distribution. Nevertheless, it should be evidenced that, notwithstanding the present updating, the knowledge of Sardinian reptiles' distribution is probably still far from being exhaustive. Thus, further investigations are strongly required for obtaining a complete picture and identifying conservation priorities in terms of isolated species/populations and areas of high diversity and endemicity. [ABSTRACT FROM AUTHOR]

The peculiar bioclimatic and geographic features of Corso–Sardinian islands may provide an ideal scenario for investigating microevolutionary processes, given their large heterogeneity of environments, which could affect dispersal and gene flow among populations, as well as processes of local adaptation. The genetic variation and differentiation among populations of the endemic lizard Archaeolacerta bedriagae were studied by allozyme electrophoresis at 20 presumptive loci. The genetic structure of this species is characterized by relatively high levels of polymorphism and low differentiation among populations. The pattern of genetic differentiation cannot be explained by genetic drift as a function of geographic distance. Genetic distance data show that genetic variation is distributed into three geographically coherent population groups and suggest a recent (Late Pleistocene) origin for the observed geographic fragmentation. The analysis of environmental correlates of allozymic variation indicates a strong correlation of the Idh-1 locus with climatic variables. The frequency of the Idh-1106 allele is negatively correlated with annual temperature, and positively correlated with annual precipitation. In addition, the observed heterozygosity at this locus decreases towards more arid climatic regimes. The results obtained support the assumption of differential selection acting on Idh-1 allozymes under diverse climates. An association between Idh-1 allozymes and local bioclimatic regimes was also observed for the sympatric lizard Podarcis tiliguerta, suggesting a key role for such selective agents on Idh-1 polymorphism in these two Corso–Sardinian lacertids. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 661–676. [ABSTRACT FROM AUTHOR]

Archaeolacerta bedriagae is a rock lizard endemic to Corsica and Sardinia. Four subspecies have been recozied to date on the basis of morphological traits. Previous allozyme investigations revealed high genetic differentiation among populations of the species. Based on these results some authors hypothesized that more than one species of Archaeolacerta may occur on Corsica and Sardinia. In this paper we investigated allozyme variation at 19 gene loci in 5 populations belonging to all subspecies of A. bedriagae in order to study genetic differentiation among populations from Corsica and Sardinia, and to compare our results with those obtained in previous studies carried out on allozyme variation and taxonomy of the species. Low levels of genetic differentiation (average Nei's D = 0.026) and heterogeneity (mean FST = 0.147) were found comparing the A. bedriagae populations, and there was no evidence of interruption or restriction of gene flow. This is in agreement with the available molecular and morphometric data, while it is not in accordance with allozyme data reported in the previous studies. Our data do not support the hypothesis of an unrecognized criptic species of Archaeolacerta in Corsica and Sardinia, and indicate that the definitive assessment of the taxonomic status of the A. bedriagae populations requires further investigation. [ABSTRACT FROM AUTHOR]