Expedition onboard RV “G. Titov” from july 17 to 30, 2020

The expedition in the southern, central and northern basins of Lake Baikal as well as in its coastal and sor zone was carried out onboard the RV “G. Titov” from July 17 to 30, 2020.

The aim of the expedition was to study species diversity and zoogeography of gastropods and bivalve mollusks, caddisflies, amphipods, polychaetes, and bryozoans in Lake Baikal and its coastal and sore zone as well as to study species composition and ecophysiology of aquatic microscopic fungi.

During the expedition, 50 stations were covered in the littoral and coastal and sore zones of Lake Baikal at depths of 0–3, 10–45, and 150–900 m.

The samples of gastropods and bivalve mollusks, caddisflies, amphipods, hydras and bryozoans were collected to study their species composition, zoogeography and molecular genetic analysis. In Lake Zama and Nizhneangarsk Sor, hydras of the species H. oxycnida were collected, whose single specimens were previously found only in Posolsk sor.

In lakes near capes Kovrizhka and Bolshaya Kosa, the Plumatella repensrepens bryozoans were collected, which will be used for the study of the genetic structure of this species.

The members of closely related species, B. dybowskiana and B. carinata, were sampled in the zone of their sympatric habitat to study mechanisms of interspecies hybridization and mitochondrial introgression.

To study the structure of mitochondrial genomes as well as to search for genomic repeats in Baikal amphipods, the members of endemic genera Pallasea и Pallasea were collected.

In the central and northern basins of Lake Baikal, soil samples were taken from depths of 150–900 m and microbiological inoculations on selective solid media were carried out for the subsequent mycological analysis.