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: Ushidome-ike (pond), Norikura highland, Azumi, Matsumoto city, Nagano Pref., Japan, November 4, 2007 by Y. Tsukii