Genus: Unicellular; planktonic; cell body elongated cylindroid, curved or twisted; both ends rounded, with spiny projections; cell wall not separated into two parts (compare to Centritractus); several chloroplasts plate-like, without pyrenoids (Guide book to the "Photomicrographs of the Freshwater Algae", 1998). Species: Cell body 5-7 (-10) μm wide (Süßwasserflora von Mitteleuropa 3, Xanthophyceae 1, 1978). Cell body with short spiny projections at both ends, 5-10 μm in diam., 50-300 μm long (Illustrations of Japanese fresh-water algae, 1977).

31 μm 63 μm 94 μm; x 640

Images of collecting locality: No.1, Karakemi marsh, Yasaka, Omachi city (formerly Yasaka village), Nagano Pref., Japan, June 4, 2007 by Y. Tsukii