Taxonomic Review of Newly Recorded Microalgal Species in Lake Environments

From April 2018 to March 2023, a survey of indigenous microalgal species was conducted across 17 locations nationwide in South Korea, covering freshwater lakes, reservoirs, and ponds. Newly observed microalgae in South Korea included 2 classes, 11 orders, 17 families, 20 genera, 36 species, 3 varieties, and 1 forma. Among them, diatoms were categorized as 1 class, 7 orders, 10 families, 13 genera, and 27 species (including 3 varieties). Dinoflagellates were recorded as 1 class, 4 orders, 7 families, 7 genera, and 9 species (including 1 forma). This study describes the species' nomenclature, references, photographs, ecology, and distribution. The 27 newly recorded diatom species in South Korea include Hantzschia dorgaliensis, Tryblionella persuadens, Delicatophycus montana, Placoneis dicephala, Gomphonema trigonocephalum, Eunotia boreoalpina, E. cisalpina, E. incisadistans, E. latiaenia, E. lat- inasuta, E. lewisii, E. metamonodon, E. ossicula, E. pseudosudetica, E. sedina, Staurosirella neopinnata, Frustulia inculta, F. kram- meri, Neidium tibetianum, Ne. triundulatum, Ne. zoigeanum, Pinnularia abaujensis var. linearis, Pinnularia borealis var. subislandica, P. reichardtii, Epithemia adnata var. saxonica, Iconella kusberi, and Surirella tientsinensis. The 9 newly recorded dinoflagellate species in South Korea include Ceratium brachyceros, C. furcoides, C. hirundinella f. austriacum, Gymnodinium palustriforme, Unruhdinium kevei, Glochidinium penardiforme, Parvodinium elpatiewskyi, Tyrannodinium edax, and Chimonodinium godlewskii. The newly ob- served microalgae showed differences in habitat preferences by species. This study is considered valuable as foundational research data for expanding the understanding of microalgal diversity in South Korea.