Species distribution modeling and molecular markers suggest longitudinal range shifts and cryptic northern refugia of the typical calcareous grassland speciesHippocrepis comosa(horseshoe vetch).
Calcareous grasslands belong to the most diverse, endangered habitats in Europe, but there is still insufficient information about the origin of the plant species related to these grasslands. In order to illuminate this question, we chose for our study the representative grassland speciesHippocrepis comosa(Horseshoe vetch). Based on species distribution modeling and molecular markers, we identified the glacial refugia and the postglacial migration routes of the species to Central Europe. We clearly demonstrate thatH. comosafollowed a latitudinal and due to its oceanity also a longitudinal gradient during the last glacial maximum (LGM), restricting the species to southern refugia situated on the Peninsulas of Iberia, the Balkans, and Italy during the last glaciation. However, we also found evidence for cryptic northern refugia in the UK, the Alps, and Central Germany. Both species distribution modeling and molecular markers underline that refugia of temperate, oceanic species such asH. comosamust not be exclusively located in southern but also in western of parts of Europe. The analysis showed a distinct separation of the southern refugia into a western cluster embracing Iberia and an eastern group including the Balkans and Italy, which determined the postglacial recolonization of Central Europe. At the end of the LGM,H. comosaseems to have expanded from the Iberian refugium, to Central and Northern Europe, including the UK, Belgium, and Germany.
Institute of Plant Sciences University of Regensburg Regensburg Germany.
Martin
M
Leipold
Institute of Plant Sciences University of Regensburg Regensburg Germany.
Simone
S
Tausch
Institute of Plant Sciences University of Regensburg Regensburg Germany.
Peter
P
Poschlod
Institute of Plant Sciences University of Regensburg Regensburg Germany.
Christoph
0000-0003-4098-6516
C
Reisch
AFLP; genetic structure; grassland; phylogeography