Grass snakes are widely distributed across the Western Palearctic. Recent phylogeographic studies provided evidence that three distinct parapatric species exist. Two of these occur in Italy, Natrix helvetica and N. natrix, and a contact zone between both taxa has been suggested for north‐eastern Italy. Moreover, previous investigations revealed for the Italian Peninsula a complex phylogeographic structure. Using mtDNA sequences and microsatellite loci, we examined the situation for mainland Italy, Sicily, Sardinia, and Corsica. Our study confirmed the occurrence of N. natrix in north‐eastern Italy. Cline analyses revealed limited gene flow between N. helvetica and N. natrix across a narrow hybrid zone. Within N. helvetica, conflicting patterns of mitochondrial and nuclear genomic differentiation were revealed. Three nuclear genomic clusters were found; one of them corresponded to no fewer than five distinct and, in part, deeply divergent and ancient mitochondrial lineages from mainland Italy and Sicily. This cluster was paraphyletic with respect to the two remaining mitochondrial lineages, each of which matched with another nuclear genomic cluster (one from Corsica plus Sardinia and another one from western Europe north of the Alps). This unexpected pattern most likely results from mainly male‐mediated gene flow and female philopatry combined with population‐density‐dependent processes such as ‘high‐density blocking’. With respect to taxonomy, we propose to synonymize N. h. lanzai Kramer, 1970 with N. h. sicula (Cuvier, 1829), acknowledging their lacking nuclear genomic differentiation. The studied hybrid zone of N. h. helvetica and N. h. sicula in Italy is wide, with a smooth cline for nuclear markers, supporting their subspecies status. We found no evidence for the distinctiveness of the two subspecies from Corsica (N. h. corsa) and Sardinia (N. h. cetti), suggesting their synonymy, but refrain from taxonomic conclusions because of small sample sizes and the endangered status of the Sardinian taxon.

In Amphibians, both positive and negative correlations between activity and full moon phase have been observed. In this study, we present data for two anuran species (Hyla intermedia and Rana dalmatina) studied in a hilly Mediterranean area of central Italy. We analysed, in a two-year survey, the relationships between the number of egg clutches laid each night and the moon phases by means of circular statistics. Moreover, the studied species exhibited clear oviposition site selection behaviour influenced, at least in H. intermedia, by moon phases. We observed the occurrence of an avoidance effect by amphibians for oviposition and specific egg-laying behaviour during moon phases around the full moon. This apparent lunar phobia was evident in both species when yearly data were pooled. On the other hand, while this pattern continued to be also evident in H. intermedia when single years were considered, in R. dalmatina it stood just in one year of study. Nonetheless, during cloudy nights, when moonlight arriving on the ground was low, the frogs' behaviour was similar to that observed in new moon phases. We interpreted the observed pattern as an anti-predatory strategy. Overall, comparisons between our own study and previous research suggest that there was insufficient evidence to establish any unequivocal patterns and that further research in this regard is needed

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This paper investigates the trophic niche of a poorly studied cave salamander, Speleomantes italicus. We examined Central Appennine hypogean populations that inhabit seven caves situated in three limestone areas in Umbria Region (Italy). Adults displayed feeding activity from May to December and the Vacuity Index analysis revealed a discontinuous trophic activity pattern throughout the year related to prey phenology. According to the qualitative analysis of the trophic spectrum, the populations in question can be defined as euryphagous, while the quantitative analysis (in terms of number and volume of preyed taxa) revealed a specialist strategy with a clear preference towards Diptera Limnobiidae. Both sexes presented similar trophic niche breadth and a high diet overlap, showing no intersexual differences. The hypogean populations of S. italicus, similarly to S. strinatii, showed a narrower trophic niche than epigeans of the same species, probably due to the limited food availability in the cave habitat.

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Anuran amphibians have traditionally been considered suitable model organisms for community ecology studies. In this paper, we review and quantitatively re-analyze the original studies published on dietary relationships among anuran communities worldwide. We re-analyzed 33 independent communities from all continents, including data on prey numbers and/or prey volumes. All datasets underwent null model re-analysis using two randomization algorithms. In addition, logistic regression models were used to identify specific assemblage patterns. We discovered three main patterns: (1) one particular algorithm (RA2, which replaces every cell in the matrix with one randomly chosen, but retains the zero structure of the matrix) performed much better at uncovering community structure; (2) nonrandom structure was more likely to occur in tropical than in nontropical regions; (3) prey volume was a better descriptor of dietary relationships than prey number when attempting to detect nonrandom structure. We showed that: pattern (1) depended on both the overall generalist nature of the anurans in general and on the mathematical properties of RA2; pattern (2) was consistent with theoretical attributes of tropicality; and pattern (3) was due to the intrinsic ecological properties of generalist organisms, which forage more or less opportunistically on prey of very different sizes; hence, when prey number is used as a diet descriptor, there is a risk of approximating different prey taxa that make different relative volume contributions to the overall diet as being of similar relevance .

Urban areas are primary causes of species' range fragmentation and reduction. However, relatively few studies have attempted to describe the habitat variables influencing the diversity and conservation of amphibians and reptiles, particularly in Mediterranean Europe and in large metropolitan areas. We explored this broad conservation ecology problem by studying the richness and diversity patterns in relation to a suite of six independent habitat variables in Rome, one of the most ancient cities of the world. We considered all the green remnant areas (n = 62) of Rome, ranging 1 to 41000 ha in size, which are interspersed within a sea of urbanized matrix. A total of 10 amphibian and 15 reptile species were studied. Their presence/absence patterns were assessed and the effects of the various habitat variables on each species were predicted by a logistic regression model. A total of 1261 presence records (404 amphibians and 857 reptiles) were analysed. Fragment size and wood size within each fragment did correlate significantly with the species richness of both amphibians and reptiles, and there was a clear threshold effect after 50 ha of wooded surface. The presence of water bodies positively affected the species distribution. One amphibian and three reptiles inhabited exclusively fragments 450 ha. The distance from the centre did not affect fragment species richness. The presence of most species of both amphibians and reptiles was positively influenced by the irregular versus circular shape of the wooded area. The legal protection of a given area did not influence the observed patterns but the total number of sheltered species. Overall, our study suggests that, in order to maintain the current diversity and population viability, it is necessary, in addition to water bodies' maintenance, to (1) preserve the wooded landscapes over 50 ha; (2) promote irregularly shaped increases in the wood surface; (3) maintain ecotonal boundaries.

The evolutionary response to interspecific competition is the partitioning of the resources used by the competing species. At the community level, the ultimate outcome of resource partitioning determines how communities evolve in terms of their species composition, explaining the distribution and abundance of organisms within natural assemblages. Despite amphibians having attracted considerable attention from population biologists, niche partitioning patterns have never been explored with a systematic approach in tailed amphibians (order Urodela). To fill this gap we tested whether Urodela communities are assembled in a non-random fashion along the trophic niche and which determinants (environmental factors and interspecific interactions) explained the observed patterns. We used a suite of statistical tools, including Generalized Linear Models and Null Models with Monte Carlo simulations, in order: (1) to explore the occurrence of non-random assemblage structure among the Urodela communities, and (2) to test environmental features (habitat) and interspecific interactions (exemplified by the overlap in species’ body size) as predictors of non-random assemblage composition. Our systematic review pointed out that: (1) the evolution of non-random structure in Urodela assemblages was determined by both biotic and abiotic factors, and (2) the food niche plays a key role in the coexistence of Urodela syntopic species. The considered assemblages showed a non-random structure influenced by diet, habitat and morphological features acting in an interactive fashion. Lawlor's RA2 algorithm was more effective than any other randomization algorithms to reveal community structure based on interspecific competition. The assemblage structure was influenced by the niche breadth of the species in the generalist–specialist nature of the resource utilization: the much higher the niche breadth similarity among species, the most likely was a non-random structure in the assemblage. In an aquatic habitat, where species can partition the space in three dimensions, assemblages composed by species overlapping in body size and generalist in feeding behaviour show non-random structure. Conversely, in terrestrial habitats, probably due to the lack of vertical stratification, differently sized species composed assemblages in a non-random fashio