Genus: Trichome without mucous sheath; straight, long, consisting of numerous cells (Illustrations of The Japanese Fresh-water Algae, 1977). Species: Trichome nearly straight, slightly tapered toward both ends, without constriction at septum, 4-6 μm wide; cell body 2.5-4 μm long, granules present along septum; pseudovacuoles also present; terminal cells variable in shape, sometimes form conical-shaped calyptra, or rounded (Illustrations of The Japanese Fresh-water Algae, 1977).

31 μm 63 μm 94 μm; x 640

Images of collecting locality: Chuo-bashi (Central bridge), Oura central park, Oura town, Gunma Pref., Japan, February 2006 by Y. Tsukii