 
 
|  Species [ var. obsoletum]: 
Cell body medium in size, broad elliptical (wider than length), 34-(39-50) μm long, 
42-(48-53)-54 μm wide, isthmus 15.5-(21-25) μm wide; 
semicells semielliptical or depressed semicircular, cell wall at basal corner thickened like a papillae; 
cell wall punctated and dotted. [ var. sitvense ]: Cell body relatively large in size, 57-(69-78) μm long, 67-(69-78) μm wide, isthmus 30-(39-42) μm wide (Illustrations of The Japanese Fresh-water Algae, 1977). 
 | 
 50 μm
 50 μm
 100 μm
 100 μm
 150 μm; x 400 :
 150 μm; x 400 : 
 31 μm
 31 μm
 63 μm
 63 μm
 94 μm; x 640
 94 μm; x 640
 
 
 
 
