* Spirogyra tenuissima (Hassall) Kützing: Vegetative cells 66-198 μm long, 10-14 μm diam., 1 chloroplast making 3.5-6 tuns in each cell (Illustrations of The Japanese Fresh-water Algae, 1977).
Spirogyra arta Jao: Vegetative cells 165-225 μm long, 15-17 μm diam., 1 chloroplast making 4-7 turns in each cell (Illustrations of The Japanese Fresh-water Algae, 1977).