title: Mountains and refuges: Genetic structure and evolutionary history in closely related, endemic Centaurea in continental Greece.
abstract: Mountains of continental Greece are one of the main Mediterranean biodiversity hotspots, very rich in endemic species. The speciation in this area might have resulted from two main factors: a complex orography and its role as a refugium during past glaciations. We have investigated genetic diversity and population structure for a group of narrow endemics of Centaurea subsect. Phalolepis, with three main goals: to investigate population structure of these narrow endemics, to check whether patterns of genetic variation are in agreement with recognized species boundaries, and to get insights into the process of diversification within this group. Fifteen populations belonging to seven species were genotyped using cpDNA (rpl32-trnL region) sequences and nuclear microsatellites (eight loci). SSR were used to assess genetic variability, to analyse molecular variance, to identify genetic barriers, to estimate recent and historical gene flow, and to carry out a model-based Bayesian clustering. Analysis of cpDNA was used to construct a haplotype network. Despite being narrow endemics, all the studied species show moderate to high SSR genetic diversity. Genetic isolation of populations is very high, with no current gene flow among them. Patterns of genetic structure indicate that there are more genetic clusters than there are currently recognized taxa. Genetic data suggest that isolation in mountain ranges and subsequent allopatric speciation would be the main driver of diversification in the group; the refugial nature of the mountains of continental Greece has allowed the maintenance of high within-population genetic diversity.
authors.affiliation: Botanic Institute of Barcelona (IBB-CSIC-ICUB), Pg. del Migdia, s/n, ES-08038 Barcelona, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: López-Vinyallonga
authors.affiliation: Botanic Institute of Barcelona (IBB-CSIC-ICUB), Pg. del Migdia, s/n, ES-08038 Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: López-Pujol
authors.affiliation: Department of Ecology & Systematics, Faculty of Biology, National & Kapodistrian University of Athens, Panepistimiopolis, GR-15784 Athens, Greece.
authors.forename: Theophanis
authors.initials: T
authors.lastname: Constantinidis
authors.affiliation: Botanic Institute of Barcelona (IBB-CSIC-ICUB), Pg. del Migdia, s/n, ES-08038 Barcelona, Spain. Electronic address: asusanna@ibb.csic.es.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Susanna
authors.affiliation: Botanic Institute of Barcelona (IBB-CSIC-ICUB), Pg. del Migdia, s/n, ES-08038 Barcelona, Spain.
authors.forename: Núria
authors.initials: N
authors.lastname: Garcia-Jacas
mesh_terms: D001499:Bayes Theorem; D005075:Biological Evolution; D031179:Centaurea / Q000235:genetics*; D017753:Ecosystem; D051456:Gene Flow; D056426:Genetic Loci; D014644:Genetic Variation; D005828:Genetics, Population; D005843:Geography; D006115:Greece; D006239:Haplotypes / Q000235:genetics; D007178:Inbreeding; D018895:Microsatellite Repeats / Q000235:genetics; D010802:Phylogeny
keywords: Centaurea; Diversification; Glacial refugia; Microsatellites; Phalolepis; cpDNA