Format: ORAL

Pau Carnicero1, Stefan dullinger2, Peter Schnswetter1

1 Department of Botany, University of Innsbruck, Innsbruck, Austria 2 2Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria

The urgent need for preserving biodiversity is beyond any doubt. However, not all components of biodiversity are usually taken into account. For a long time, conservation efforts have targeted ecosystems or species; in recent years, a new focus has been put on cryptic intraspecific diversity on the gene level. In mountain ranges of the temperate regions, intraspecific diversity has been strongly determined by the Pleistocene glaciation cycles. We here focus on the Pyrenees, a hotspot of plant diversity in western Europe with more than 4,300 plant species, but still lacking an assessment of intraspecific diversity features. We aimed to reconstruct the response of alpine plants to the last glacial period and to identify areas of high intraspecific phylogenetic endemism, which are ultimately of special interest for conservation. For this purpose, we used a multi-species comparative phylogeography approach combining molecular data (RADseq) and retrospective as well as prospective distribution modelling of species and intraspecific lineages. Our results show a highly structured distribution of intraspecific diversity, which allows to formulate the first molecular-based hypothesis of glacial refugia for alpine plants in the Pyrenees. Refugia of calcicolous species were in weakly glaciated ranges south of the main chain, while silicicolous species show a pattern of multiple geographically incongruent genetic groups, indicative of species-specific reduced-size refugia and nunatak survival. The easternmost Pyrenees emerge as a common refugium for most of the studied species and contain high levels of phylogenetic endemism, rendering them an area of major interest for conservation of intraspecific diversity.