Fig. 2. SEM. Left valve. Anterior end widely escavated and curved.
Fig. 3. SEM. Posterio-lateral view of left valve. Intercalary band smooth.
Fig. 4. SEM. Valve surface with shallow depressions: round to oblong with smooth margins. Round trichocyst pores occassionally situated in the depressions (arrows).
Fig. 5. SEM. Periflagellar area: deep, V-shaped, curved depression. Periflagellar plate is prominent, thin and inclined (arrows). Transverse flagellum (arrowheads) present.
Fig. 6. SEM. Ejected trichocysts situated in furrowed depressions on valve surface (arrows).
Fig. 7. LM. Right valve: large periflagellar plate visible (arrow).
Fig. 8. LM. Left valve. Large posterior nucleus. N=nucleus