Fig. 1. LM of live cells in a chain.
Objective x 25.
Straight or curved cells are organized in helical chains. Oval valves have one central labiate process and low horns. Valve faces are flat to concave in broad girdle view. Windows are almost square.
Apical axis measure10-33 µm. In SEM 38-42 valve areola in 10 µm are visible.