Genetic and morphological characterization of a Lake Ohrid endemic, Salmo (Acantholingua) ohridanus with a comparison to sympatric Salmo trutta
Abstract:Analysis of both uni‐(two mtDNA gene sequences) and bi‐parentally (seven microsatellite loci) inherited genetic markers, together with analysis of 40 morphological characters, described Salmo ohridanus as a highly divergent member of the genus Salmo. Based on comparative substitution rate differences at the cytochrome b gene, and a rough estimated age of the Salmo trutta complex (i.e. at least 2 million years), the S. ohridanus and Salmo obtusirostris clade probably split from a common ancestor of brown trout Salmo trutta >4 million years ago, overlapping with minimum age estimates of the formation of Europe's oldest freshwater habitat, Lake Ohrid. Comparative analysis with Lake Ohrid brown trout (known regionally as Salmo letnica), supported the notion that these fish have more recently colonized the lake and phylogenetically belong to the Adriatic lineage of brown trout. It is further suggested that species‐specific saturation in the mtDNA control region underestimated the divergence between S. ohridanus and S. trutta. Evidence of rare hybridization between S. ohridanus and Lake Ohrid brown trout was seen at both mtDNA and microsatellite markers, but there was no support for extensive introgression.
Document Type: Regular Paper
Affiliations: 1: Karl-Franzens Universität Graz, Institut für Zoologie, Universitätsplatz 2, A-8010 Graz, Austria, 2: Irkutsk State University, Biological Faculty, ul K. Marksa 1, Irkutsk, 664003 Russia and 3: University of Ljubljana, Biotechnical Faculty, Department of Animal Science, Groblje 3, 1230 Domžale, Slovenia
Publication date: March 1, 2006