Silica-scaled protists (Chrysophyceae, Centroplasthelida, Thaumatomonadida and Rotosphaerida) in waters bodies of Kotelny Island, Russian Arctic

• Published in: Polar biology 2023-09, Vol.46 (9), p.895-913
• Main Authors: Bessudova, Anna Yu, Gabyshev, Viktor A., Firsova, Alena D., Likhoshway, Yelena V.
• Format: Article
• Language: English
• Subjects: Aquatic ecosystems; Archipelagoes; Arctic research; Biodiversity; Biogeography; Biomedical and Life Sciences; Colonization; Ecology; Electron microscopy; Eocene; Flora; Fresh water; Freshwater; Freshwater ecosystems; Inland water environment; Islands; Life Sciences; Microbiology; Oceanography; Original Paper; Plant Sciences; Protists; Silica; Silicon dioxide; Species; Transmission electron microscopy; Zoology
• ISSN: 0722-4060; 1432-2056
• DOI: 10.1007/s00300-023-03173-1

Microeukaryotes, including silica-scaled protists, are ubiquitous in freshwater ecosystems. There are several hypotheses of their colonization and expansion around continental freshwater reservoirs. There is still a lack of solid knowledge whether silica-scaled protists live on Arctic islands remote from the mainland? If yes, how did they populate these sites and how diverse they are. Here we, present the results of biodiversity studies of silica-scaled protists from water bodies of Kotelny Island (75° 20′ N  141° 00′ E) in the Russian Arctic. The research area is a part of the New Siberian Islands archipelago. Transmission electron microscopy allowed us to find a total of 25 species of silica-scaled protists in the water bodies studied; 17 of them were silica-scaled chrysophyte species from the genera Chrysosphaerella (1), Paraphysomonas (2), Spiniferomonas (2), Mallomonas (3), Synura (9), while 8 species were heterotrophic protists, including 6 species of centrohelid heliozoans from the genera Acanthocystis (1), Choanocystis (2), Raineriophrys (1), Raphidocystis (1), Pterocystis (1); one thaumatomonad flagellate species from the genus Thaumatomastix ; and one rotosphaerid species from the genus Rabdiophrys . Importantly, silica-scaled protist species related to the ancient Eocene flora, along with cosmopolitan and widespread species, were found in sampling sites of Kotelny Island. We also discuss the biogeographic distribution of silica-scaled protists found on this remote Arctic island.