Genus: Similar to Chlamydomonas, but
lacks chloroplasts; leucoplasts present instead; two equal-length flagella, usually with many starch granules;
pyrenoid absent; stigma present or absent; 2 or 4 contractile vacuoles anteriorly located;
asexual reproduction by zoospores; sexual reproduction iso- or anisogamous
(Illustrated Guide, 2000).
Species: Cell body nearlly spherical; 8-17 μm in diam.; papillae absent; 4 contractile vacuoles anteriorly located (An Illustrated Guide to Freshwater Zooplankton in Japan, 2000).