MICROSATELLITE POLYMORPHISM WITHIN TWO LAKE BAIKAL OILFISH SPECIES (COMEPHORUS LACEPEDE, 1801)

Current genetic structure of European vendace Coregonus albula (L.) populations in Latvia after multiple past translocations

The European vendace Coregonus albula (L.), also known as the European cisco, is a widespread fish species in northern Europe, often regarded as an example of a glacial relict. It is an economically valuable fish and has been artificially propagated in Latvia since 1900. Despite past translocations of larvae and fry and its current protection status, it can be found in only 15 Latvian lakes. We used nine microsatellite markers to study vendace populations from nine Latvian lakes. A higher mean allelic richness and private allelic richness in Lake Riču suggest that this population may be indigenous. Three complementary clustering methods revealed similar grouping into three distinct genetic groups. According to the results, European vendace populations in the Latvian lakes studied may currently be a mixture of several other populations after multiple translocations.

Molecular divergence and speciation of Baikal oilfish (Comephoridae): facts and hypotheses

Sympatric speciation was studied in two sister species of cottoid fish from Lake Baikal (East Siberia): big golomyanka or Big Baikal oilfish (Comephorus baicalensis Pallas, 1776) and small golomyanka or Little Baikal oilfish (C. dybowski Korotneff, 1905). Analysis of nucleotide sequences of mitochondrial cytochrome b gene showed that the Little Baikal oilfish (LBO) formed a single population in the lake, whereas the Big Baikal oilfish (BBO) was divided into two genetic groups - BBOI and BBOII, which were not separated geographically. Phylogenetic analysis showed that BBO is a more ancient species than LBO and that the paraphyletic origin of LBO is from the BBO genetic lineage within the genus Comephorus. Population-genetic structure and phylogenetic relationships between the two golomyanka species are considered to be a consequence of paleoenvironmental events that took place in the Baikal region during the past hundreds of thousand years.