Genus: Subaerial algae or a algal component of lichens; unicells; cell body 10-15 μm in diam.,
chlorplast(s) star-shaped or aggregated, with a single pyrenoid at the center
(Illustrations of The Japanese Fresh-water Algae, 1977).
cell body football-shaped, 18 μm long, 14 μm wide,
x 400, x 640, Japan, December 1998 by Y. Tsukii