The Study of the Diversity of Hydrobionts from Listvennichny Bay of Lake Baikal by DNA Metabarcoding

The taxonomic diversity of hydrobionts from Listvennichny Bay was studied by DNA metabarcoding. The sequencing of a gene fragment (313 bp) of mitochondrial DNA encoding the first subunit of cytochrome c oxidase (COI) was performed using an Illumina MiSeq after amplification from internal primers (mlCOIintF, jgHCO2198). Bioinformatic analysis of COI reads revealed 187 OTUs (operational taxonomic units), among which Arthropoda, Annelida, Mollusca, and Plathelminthes prevail, accounting for 52, 30, 10, and 4%, respectively. In general, the species diversity of the bay’s fauna by the Shannon index (3.2 bits) is comparable to other areas of Lake Baikal. The most diverse composition of taxa (22 OTUs) of the species rank falls on the larvae of chironomids, which confirms the effectiveness of the method for identifying juvenile stages of invertebrates. The research results are the first step toward improving the system of hydrobiological monitoring of Lake Baikal based on the synthesis of molecular genetic diagnostics of invertebrates and classical morphological taxonomy.