Molecular phylogeographic analyses of the loach Oxynoemacheilus bureschi reveal post-glacial range extensions across the Balkans

Authors

  • A. ŠEdivá,

    Corresponding author
    1. Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburská 89, 277 21 Liběchov, Czech Republic
    2. Institute of Zoology, Slovak Academy of Sciences, Dúbravská cesta 9, 845 06 Bratislava, Slovakia
    Search for more papers by this author
  • A. Apostolou,

    1. Institute of Zoology, Bulgarian Academy of Sciences, 1 Tsar Osvoboditel Bvld., 1000 Sofia, Bulgaria
    Search for more papers by this author
  • J. Kohout,

    1. Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburská 89, 277 21 Liběchov, Czech Republic
    2. Research Institute of Fish Culture and Hydrobiology at Vodňany, University of South Bohemia, České Budějovice, Czech Republic
    Search for more papers by this author
  • J. Bohlen

    1. Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburská 89, 277 21 Liběchov, Czech Republic
    Search for more papers by this author

Tel.: +420 315 639558; fax: +420 315 639510; email: sediva@iapg.cas.cz

Abstract

Rivers on the Balkan Peninsula can be separated into ichthyofaunistic areas with different endemic fish species. The Vardar River contains a particularly large number of endemics, indicating its complete and long-term isolation from neighbouring river systems. One of the few species shared with other rivers is the loach species Oxynoemacheilus bureschi. In this study, the genetic analyses of 175 individuals of O. bureschi from 17 sites, covering the entire distribution of the species, including the Rivers Vardar (= Axios), Struma (= Strymon), Mesta (= Nestos) and Danube, were performed using one mitochondrial and one nuclear marker. Genetic differentiation among populations was in general low. Shared haplotypes were common and occurred even between distant localities and different river systems. This points to a high degree of gene flow among populations and rejects the hypothesis that the population in the Vardar River represents a relict from an early colonization of the Balkan Peninsula. In contrast, the results suggest that populations in the Vardar River, as well as those in the Danube River, are of recent origin, and a human-mediated introduction cannot be excluded. On the other hand, the populations in the Aggitis River, a left tributary of the lower Struma River, were clearly separated from the rest of the species and represent a long-term isolated lineage. Demographic analyses suggest a recent population expansion for O. bureschi, in which the population in the Aggitis River was not involved.

Ancillary