Phylogenetic and Phylogeographical structure of Saxifraga callosa: Haplotype richness and identification of hybrids in refugial areas

Saxifraga callosa is a species spread in South-Easren France an italy with high diffusion in Maritime Alps. This species lives in more or less vertical limestone rocks at an altitude of between 200 and 2,000 m a.s.l. and it ranges from South-western Alps (Cottian and Maritime Alps, Provence) through the Apuane Alps and the Apennines to southern Italy, sardinia and Sicily. A multiple molecular approach, usinf ITS, AFLP, chrloroplast sequences and microsatellites, allowed a comprehension of the intra and inter specific relationships and the construction of a haplotype network. Genetic variability within populations was estimated by the number of polymorphic aplotypes. The study of haplotypes legitimated conclusions on phylogeographical inferences across the species assortment and on the identification of diversity areas in the Maritime and Apuane Alps interpreted as peripheral glacial refugia during the Ice Ages. Moreover, the application of the 'New Hybrids' software to AFLP data-sets recognised S. lantoscana as a natural outcross between S. callosa subsp. callosa and S. cochlearis.