A Study on the Diversity of Previously Unrecorded Diatom Species Observed in Freshwater Rivers and Tributaries

This study is a foundational analysis of the diversity of unrecorded diatoms observed in freshwater regions, such as rivers and streams, in South Korea. From March 2019 to April 2022, a survey of native microalgae species was conducted across seven small rivers, streams, and creeks in areas including Jangsu-gun, Muju-gun in Jeollabuk-do, and Sangju-si, Andong-si, Cheongsong-gun, Yecheon-gun in Gyeongsangbuk-do, and Sancheong-gun in Gyeongsangnam-do. As a result, a total of 1 class, 6 orders, 7 families, 7 genera, 8 species(including 2 varieties) of newly observed diatoms were identified in South Korea. This study provides species no- menclature, references, photographs, ecology, and distribution information for these diatoms. The eight newly recorded diatom spe- cies in South Korea include Achnanthes tumescens, Tryblionella salinarum, Cymbella excisa, Cymbella neocistula var. islandica, Gomphonella olivaceoides, Eunotia monodontiforma, Pinnularia subgibba var. lanceolata, and Surirella terryi. Additionally, their hab- itat and ecological characteristics were analyzed. This study contributes to expanding the diversity of biological resources in Korea and is expected to serve as a foundational research resource for studying freshwater ecosystems in Korea. The findings may further serve as essential baseline data for future efforts in biodiversity conservation and water quality management.