Silica-scaled Chrysophytes in Small Lakes of the Lower Yenisei Basin, the Arctic

Chrysophytes are a characteristic component of phytoplankton in oligotrophic arctic and subarctic lakes. In this study. scanning electron microscopy has been used to analyse the species composition and abundance of silica-scaled chrysophytes in eight small lakes of the Lower Yenisei basin. A total of 38 species and intraspecific taxa have been recorded, including representatives of the genera Mallomonas (12 taxa), Spiniferomonas (9), Synura (8), Chrysosphaerella (4), and Paraphysomonas (5). Along with 23 widespread taxa, their list includes such rare species as Paraphysomonas uniformis hemiradia, P. bandaiensis, Spiniferomonas cornuta, S. crucigera, S. minuta, S. triangularis, S. trioralis f. cuspidata, Mallomonas alata f. hualvensis, M. crassisquama var. papillosa, M. pseudomatvienkoae, M. flora cf. palermii, Synura punctulosa, S. truttae, S. mollispina, S. curtispina, and S. synuroidea. It should be noted that Mallomonas pseudomatvienkoae, M. flora cf. palermii, Synura truttae, and S. synuroidea have not been previously described from water bodies of Russia. Statistical analysis revealed that the diversity and content of scaled chrysophyte species in the studied lakes of the Lower Yenisei basin are significantly influenced by the concentration of silicon. water conductivity, and total ions.