Genus: Cell body elongated spindle in shape, straight or curved, sharply pointed at both ends; (Guide book to the "Photomicrographs of the Freshwater Algae", 1998). Species: Cell body elongate fusiform, tapering toward the sharply pointed ends, sigmoid, undulate to helicoidally twisted (1 - 1.5 turns), 16-18 μm long between the ends, 1-2 μm wide; two chloroplasts, parietal, entending into the ends, without pyrenoids; cell division produces 2, 4 or 8 "autospores" (Photomicrographs of the Freshwater Algae, 1996).

31 μm 63 μm 94 μm; x 640