The Contact Zone of Phylogenetic Lineages of Freshwater Fish in Arctic Eurasia: Genetic Polymorphism of Coregonid Populations

Abstract

The reconstruction of regional fauna history is very important in the context of recent climate change and anthropogenic transformation. We analyzed the mitochondrial nd1 gene polymorphism in populations of whitefish Coregonus lavaretus and certain widespread Eurasian ciscoes species: vendace Coregonus albula and least cisco Coregonus sardinella, inhabiting waterbodies from the Anadyr River in the east (the Pacific Ocean basin) to Loch Lomond in the west (the Atlantic Ocean basin). Distinct phylogenetic lineages and secondary contact zones have been found in these species. Most of these are species-specific with the exception of the zone from the Pechora River basin to at least the western part of the Taymyr Peninsula, in which whitefish, vendace, and least cisco share with each other and with various cold-water hydrobionts. We associate differences in the geographical position and propagation of the secondary contact regions with the species-specific morpho-ecological features, in particular, with the ability for long-term migrations. Based on the data obtained, we also discuss certain limitations of the phylogeography and phylogeny of the considered coregonid species and the correctness of the taxonomic status of certain populations or their groups.