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).
Trebouxia sp. ? (uncertain class, Chlorophyceae),
cell body ~20 μm in diam., no flagella, chloroplasts parietal and star-shaped,
a parental cell divided into 4 daughter cells,
x 400, x 640, Binnuma River, Omiya City, Saitama Pref., Japan, September 2000, by Y. Tsukii
94 μm; x 640