THE SYSTEMATIC STUDY OF COELASTRELLA FROM CHINA

The genus Coelastrella was taxonomically positioned within the family Scenedesmaceae (Sphaeropleales, Chlorophyceae) by Chodat in 1922, with Coelastrella striolata designated as the type species. In recent years, many studies have highlighted the promising potential of the genus Coelastrella in natural carotenoids and lipids production, as well as wastewater treatment. So far, 18 species and 2 varieties of this genus have been reported worldwide. However, the study on this genus has been relatively limited in our country, leading to gaps in our understanding of its diversity and geographical distribution. This study aimed to address these gaps by collecting 29 Coelastrella strains from various regions in China. Morphological and phylogenetic analyses were conducted using 18S rDNA, ITS, and tufA molecular markers. Amony them, the tufA showed the highest efficiency in the taxonomic revision of genus Coelastrella. The results systematically organized 10 Coelastrella species and 2 varieties previously recorded in China. Additionally, three newly recorded species were discovered, that were Coelastrella multiriata, Coelastrella terrestris, and Coelastrella aeroterrestrica. Furthermore, the morphological difference were summerized among the four phylogenetic clades of this genus. The discovery of these species has filled the void of core Coelastrella branch specimens in China, enhancing the species diversity of the Coelastrella genus in our country. This finding serves as a foundation for further classification revision and resource development.