Multilocus phylogeography of Italian Moorish geckos adds insights into the evolutionary history of European populations
Author(s)
Date Issued
2023
Type
article
Volume
53
Issue
2
Start Page
129
End Page
141
Journal
Abstract
Geckos of clade III of the Tarentola mauritanica species complex are wide- spread throughout southern Europe and northern Africa. We investigated the genetic variability of the Italian populations by performing a widespread sam- pling throughout the mainland and the two main islands of Sicily and Sardinia. We analysed 199 newly generated sequences of the mitochondrial 16S rRNA gene and 269 nuclear genotypes inferred from nine microsatellite loci from 307 individuals. We found 13 new mitochondrial haplotypes in Italy, whereas pre- vious findings reported a single haplotype widespread throughout the country and in the rest of Europe, which currently make Italy the centre of genetic diversity of this taxon. There was no evidence of mitochondrial DNA structur- ing with geographic correlation. At the population genetic level, our multilo- cus approach based on nuclear markers returned a shallow genetic structure. Nonetheless, we disclosed the presence of at least four distinct genetic clusters (namely the Adriatic, two Tyrrhenian and the Calabrian clusters). Our find- ings do not support the two hypotheses proposed to explain the low level of mi- tochondrial polymorphism in this taxon, namely the genetic hitch-hiking due to selective sweep and the historical human-mediated colonization hypoth- eses. Based on the fossil record, the presence in Italy of this taxon since the Pleistocene Epoch is plausible. Given the discordance in genetic structure be- tween mitochondrial and nuclear DNA, the exact role of the Italian Peninsula in shaping the observed patterns of genetic diversity during the Pleistocenic climatic oscillations needs further investigation.