title: Nuclear and mitochondrial phylogeography of the European fire-bellied toads Bombina bombina and Bombina variegata supports their independent histories.
abstract: Exact location and number of glacial refugia still remain unclear for many European cold-blooded terrestrial vertebrates. We performed a fine-scaled multilocus phylogeographic analysis of two Bombina species combining mitochondrial variation of 950 toads from 385 sites and nuclear genes (Rag-1, Ncx-1) from a subset of samples to reconstruct their colonization and contemporary variation patterns. We identified the lowlands northwest of the Black Sea and the Carpathians to be important refugial areas for B. bombina and B. variegata, respectively. This result emphasizes the importance of Central European refugia for ectothermic terrestrial species, far north of the Mediterranean areas regarded as exclusive glacial refugia for the animals. Additional refugia for B. variegata have been located in the southern Apennines and Balkans. In contrast, no evidence for the importance of other east European plains as refugial regions has been found. The distribution of mtDNA and Ncx-1 variation suggests the presence of local refugia near the Black Sea for B. bombina; however, coalescent simulations did not allow to distinguish whether one or two refugia were present in the region. Strong genetic drift apparently accompanied postglacial expansions reducing diversity in the colonization areas. Extended sampling, coupled with the multilocus isolation with migration analysis, revealed a limited and geographically restricted gene flow from the Balkan to Carpathian populations of B. variegata. However, despite proximity of inferred B. bombina and B. variegata refugia, gene exchange between them was not detected.
authors.affiliation: Department of Comparative Anatomy, Institute of Zoology, Jagiellonian University, Gronostajowa 9, 30-387 Kraków, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Fijarczyk
authors.forename: Krystyna
authors.initials: K
authors.lastname: Nadachowska
authors.forename: Sebastian
authors.initials: S
authors.lastname: Hofman
authors.forename: Spartak N
authors.initials: SN
authors.lastname: Litvinchuk
authors.forename: Wiesław
authors.initials: W
authors.lastname: Babik
authors.forename: Michał
authors.initials: M
authors.lastname: Stuglik
authors.forename: Günter
authors.initials: G
authors.lastname: Gollmann
authors.forename: Lukáš
authors.initials: L
authors.lastname: Choleva
authors.forename: Dan
authors.initials: D
authors.lastname: Cogălniceanu
authors.forename: Tanja
authors.initials: T
authors.lastname: Vukov
authors.forename: George
authors.initials: G
authors.lastname: Džukić
authors.forename: Jacek M
authors.initials: JM
authors.lastname: Szymura
mesh_terms: D025041:Animal Migration; D000818:Animals; D001001:Anura / Q000235:genetics*; D059038:Black Sea; D004272:DNA, Mitochondrial; D017753:Ecosystem; D005060:Europe; D051456:Gene Flow; D040961:Genetic Drift; D014644:Genetic Variation; D019083:Mediterranean Region; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics*; D058974:Phylogeography; D011153:Population / Q000235:genetics; D019831:Sodium-Calcium Exchanger / Q000235:genetics
chemical_list: D004272:DNA, Mitochondrial; D009687:Nuclear Proteins; D019831:Sodium-Calcium Exchanger; C110374:sodium-calcium exchanger 1