Genus: Cell body crescent in shape (long, curved, tapered at both ends); cross section rounded;
cell wall smooth or with longitudinal lines, bands on the cell wall in some species;
chloroplast laminae ridged and radially arranged, which makes cross section star-shaped;
pyrenoids aligned or scattered (Illustrations of The Japanese Fresh-water Algae, 1977).
Species:
Closterium rectimarginatum ?,
cell body 122 μm long, 11 μm wide, L/W=11.1,
x 640, Kareki-numa marsh, Nikko city (formerly Fujiwara town), Tochigi Pref., Japan, August 2, 2008, collected by Eizaburo Tsukii, photo by Y. Tsukii 31 μm
63 μm
94 μm; x 640
Cell body μm long, μm wide, L/W=, x 640
Images of collecting locality:
Kareki-numa marsh, Nikko city (formerly Fujiwara town), Tochigi Pref., Japan, August 2, 2008 by Eizaburo Tsukii