Phylogeographic pattern of the high-alpine plant species Eritrichium nanum (Boraginaceae) within the Carpathians

Abstract

The Carpathians represent not only a European hotspot of plant diversity for both species richness and endemism, but also an important stepping-stone area in historical migrations between the flora of the Asian and European mountain systems and a starting point of postglacial recolonizations for many species. Yet, until recent years, phylogeographical studies for alpine or arctic-alpine plants were focused on the Alps, whereas peripheral mountain ranges, including the Carpathians, were either neglected or insufficiently sampled. In this study, we aimed to complement the Alpine phylogeographic structure of an emblematic high-alpine European endemic taxon, Eritrichium nanum, by focusing on the Carpathian range of the species. We sampled nine populations from the South-Eastern Carpathians and performed ITS1 sequencing and AFLP fingerprinting. In case of ITS1 region, all the populations, no matter of their geographic origin, presented the same ribotype. The AFLP analysis indicated that, within the Carpathians, the extant populations of E. nanum comprised two major allopatric lineages. One important result of the research was the discovery that the species’ sole important genetic break was located in the Southern Carpathians, separating populations of the Retezat Mountains from all the others in the Carpathians.