Genus: Cell body cylindroid or spindle in shape; spiral ribbon-like chloroplasts or laminae of the chloroplast arranged spirally around central rod (Illustrations of The Japanese Fresh-water Algae, 1977). Species : Vegetative cells large, cigar-shaped, 60-334 μm long, 10-30.4 μm diam., spiral band-form chloroplasts (Illustrations of The Japanese Fresh-water Algae, 1977).

31 μm 63 μm 94 μm; x 640

Images of collecting locality: No.2, a marsh pond at Mitsuishi marsh, Hachimantai city, Iwate Pref., Japan, August 13, 2008 by Y. Tsukii