(Süßwasserflora von Mitteleuropa 9, Chlorophyta I, 1983).
Mesostigma viride Lauterborn 1894,
cell body curved disc-shaped, 20 μm long, 21 μm wide (including outer scaled sheath),
anterior end broadened and curved inward, circular stigma located at the center of the disc-shaped cell body,
two flagella inserted at anterior ventral side,
chloroplast peripheral, two spherical pyrenoids anteriorly located,
x 640, Sannoh park, Nishi-ku, Saitama city, Saitama Pref., Japan, July 4, 2004 by Y. Tsukii
94 μm; x 640