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).

50 μm 100 μm 150 μm; x 400 : 31 μm 63 μm 94 μm; x 640