Test small ovoid in shape with siliceous scales in alternating transverse rows; pseudostome terminal;
cell body does not fill the test completely; nucleus posterior (Kudo, 1966).
Paulinella chromatophora, with endosymbiotic cyanobacteria,
cell body 25-28 μm long, 19 μm wide,
x 640, Heisei-no-mori Park, Kawashima town, Saitama city, Saitama Pref., Japan, June 2002 by Y. Tsukii
94 μm; x 640