Molecular diversity of the genus Cryptomonas (Cryptophyceae) in Russia

Molecular data were used to revise the diversity of the genus Cryptomonas in Russia, using samples collected across nine geographic regions within Russia from 2015–2019. Several molecular markers were used: nuclear SSU, LSU and ITS2 rDNA, and plastid psbA. In total, 24 species of the genus Cryptomonas were identified in the country’s fresh waters based on 122 different strains. Six new species were identified and are described here (Cryptomonas matvienkoae sp. nov., C. furtiva sp. nov., C. paludosa sp. nov., C. ursina sp. nov., C. kisselevii sp. nov. and C. meshchorana sp. nov.), and three taxa are emended (Cryptomonas skujae, C. platyuris and C. obovata). These new and emended species group in clades with the previously described species or represent new lineages on the phylogenetic tree. Seven morphospecies, previously reported in Russia, are confirmed by molecular methods, and two unidentified taxa are also reported. HIGHLIGHTS Molecular investigations of the genus Cryptomonas in Russia revealed 24 species.Descriptions of three species were emended.Six species new to science were described. Molecular investigations of the genus Cryptomonas in Russia revealed 24 species. Descriptions of three species were emended. Six species new to science were described.