Detecting a hierarchical genetic population structure: the case study of the Fire Salamander (Salamandra salamandra) in Northern Italy

The multi-step method here applied in studying the genetic structure of a low dispersal and philopatric species, like the Fire Salamander Salamandra salamandra, was proved to be effective in identifying the hierarchical structure of population living in broadleaved forest ecosystems in Northern Italy. In this study 477 salamander larvae, collected in 28 sampling populations (SPs) in the Prealpine and in the foothill areas of Northern Italy, were genotyped at 16 specie-specific microsatellites. SPs showed a significant overall genetic variation (Global FST=0.032, p<0.001). The genetic population structure was assessed by using STRUCTURE 2.3.4. We found two main genetic groups, one represented by populations inhabiting the Prealpine belt, which maintain connections with those of the Eastern foothill lowland (PEF), and a second group with the populations of the Western foothill lowland (WF). The two groups were significantly distinct with a Global FST of 0.010 (p<0.001). While the fi...