Genus: Colonies of 4 (or 2, 8, 16) cells attached side by side, arranged linearly or zigzag;
cell body elliptical or spindle or crescent in shape; terminal cells with spiny projections in many species;
cell wall usually smooth, but in some species granulated or dented or ridged
(Illustrations of The Japanese Fresh-water Algae, 1977).
Species [ var. ellipsoideus ]: (Illustrations of The Japanese Fresh-water Algae, 1977).
*Under the SEM observation, the cell wall ultrastructure is that of D. maximus. But cells are much small for that taxon (communicated by Dr. E. Hegewald at Research Centre Jülich, ICG III Phytosphere, Germany, December 2005).