Phylogenomic insights into the diversity and evolution of Palearctic vipers.

Despite decades of molecular research, phylogenetic relationships in Palearctic vipers (genus Vipera) still essentially rely on a few loci, such as mitochondrial barcoding genes. Here we examined the diversity and evolution of Vipera with ddRAD-seq data from 33 representative species and subspecies. Phylogenomic analyses of âˆ¼ 1.1 Mb recovered nine major clades corresponding to known species/species complexes which are generally consistent with the mitochondrial phylogeny, albeit with a few deep discrepancies that highlight past hybridization events. The most spectacular case is the Italian-endemic V. walser, which is grouped with the alpine genetic diversity of V. berus in the nuclear tree despite carrying a divergent mitogenome related to the Caucasian V. kaznakovi complex. Clustering analyses of SNPs suggest potential admixture between diverged Iberian taxa (V. aspis zinnikeri and V. seoanei), and confirm that the Anatolian V. pontica corresponds to occasional hybrids between V. (ammodytes) meridionalis and V. kaznakovi. Finally, all analyzed lineages of the V. berus complex (including V. walser and V. barani) form vast areas of admixture and may be delimited as subspecies. Our study sets grounds for future taxonomic and phylogeographic surveys on Palearctic vipers, a group of prime interest for toxinological, ecological, biogeographic and conservation research.

Effects of temperature and precipitation changes on shifts in breeding phenology of an endangered toad.

In the last century, a plethora of species have shown rapid phenological changes in response to climate change. Among animals, amphibians exhibit some of the greatest responses since their activity strongly depends on temperature and rainfall regimes. These shifts in phenology can have negative consequences for amphibian fitness. Thus, understanding phenological changes in amphibians is pivotal to design conservation actions to mitigate climate change effects. We used data on Common Spadefoot Toad (Pelobates fuscus) reproductive migration to wetlands over a period of 8 years in Italy to (i) identify the factors related to breeding migrations, (ii) assess potential phenological shifts in the breeding period, and (iii) determine which climatic factors are related to the observed phenological shifts. Our results showed that toads migrate to spawning sites preferably in early spring, on rainy days with temperatures of 9-14 °C, and with high humidity. Furthermore, despite an increase in average temperature across the study period, we observed a delay in the start of breeding migrations of 12.4 days over 8 years. This counterintuitive pattern was the result of a succession of hot and dry years that occurred in the study area, highlighting that for ephemeral pond breeders, precipitation could have a larger impact than temperature on phenology. Our results belie the strong presumption that climate change will shift amphibian phenology toward an earlier breeding migration and underline the importance of closely investigating the environmental factors related to species phenology.

Skull osteology of Vipera walser (Squamata, Viperidae): Description, variability, ontogeny, and diagnostic characters in comparison to other Italian vipers.

Vipera walser is the most recently recognized European viper. This rare species is endemic to a small area in the Piedmont Alps of Italy, but its closest relatives are found among the Caucasian viper species. In order to provide a starting point for a phylogenetic and biogeographic investigation based on osteology, and including fossils remains, we analyzed four specimens of V. walser and compared them with specimens of the four other Italian viper species. Based on these specimens, we improved the diagnosis of V. walser and provided a first evaluation of intraspecific variability and ontogenetic variation. The skull of V. walser is subject to significant variation, most likely related to ontogeny in some cases (i.e., development of the parietal crest, development of the basioccipital process, shape of the posterior margin of the parabasisphenoid, shape of the quadrate). Based on the studied material, it is possible to distinguish V. walser from the other Italian vipers by the shape of the occipital crest of the supraoccipital, which is posteriorly directed, whereas it is laterally directed in the other species. The osteological diagnosibility provides further support for the validity of V. walser as a distinct species from Vipera berus.

Italian odonates in the Pandora's box: A comprehensive DNA barcoding inventory shows taxonomic warnings at the Holarctic scale.

The Odonata are considered among the most endangered freshwater faunal taxa. Their DNA-based monitoring relies on validated reference data sets that are often lacking or do not cover important biogeographical centres of diversification. This study presents the results of a DNA barcoding campaign on Odonata, based on the standard 658-bp 5' end region of the mitochondrial COI gene, involving the collection of 812 specimens (409 of which barcoded) from peninsular Italy and its main islands (328 localities), belonging to all the 88 species (31 Zygoptera and 57 Anisoptera) known from the country. Additional BOLD and GenBank data from Holarctic samples expanded the data set to 1,294 DNA barcodes. A multi-approach species delimitation analysis involving two distance (OT and ABGD) and four tree-based (PTP, MPTP, GMYC and bGMYC) methods was used to explore these data. Of the 88 investigated morphospecies, 75 (85%) unequivocally corresponded to distinct molecular operational units, whereas the remaining ones were classified as 'warnings' (i.e. showing a mismatch between morphospecies assignment and DNA-based species delimitation). These results are in contrast with other DNA barcoding studies on Odonata showing up to 95% of identification success. The species causing warnings were grouped into three categories depending on if they showed low, high or mixed genetic divergence patterns. The analysis of haplotype networks revealed unexpected intraspecific complexity at the Italian, Palearctic and Holarctic scale, possibly indicating the occurrence of cryptic species. Overall, this study provides new insights into the taxonomy of odonates and a valuable basis for future DNA and eDNA-based monitoring studies.