Order: Filamentous algae without branching; cell body mostly cylindrical. Family: Cellwall shows H shape in transverse section; chloroplasts reticulatedwithout pyrenoids. Genus: Same as family. Species:

31 μm 63 μm 94 μm; x 640

Images of collecting locality: No.3, Ohyachi, Akita-Hachimantai, Kazuno city, Akita Pref., Japan, September 21, 2007 by Y. Tsukii