Acanthocystis astrakhanensis Mikrjukov, 1993
Diagnosis: Cells are about 30 µm in diameter with tangential plate-scales and one type of radial spine-scales in the periplast. Spine-scales straight, 8–10 µm long; shaft cylindrical, about 0.3 µm in diameter, of uniform thickness; apex divided into two furcae, about 0.5 µm long, tapering towards obtuse ends without secondary bifurcation. Plate-scales oval, 3.0–3.2 x 1.6 µm with a clear axial rib.
Ecology: Fresh and brackish waters. Volga outfall, Black Sea, Crimea coast.