Description of Dinophysis rotundata:
The cells are round-oval in lateral view and ellipsoidal in apical view. The epitheca is rounded and extends beyond the cingular list (i.e. it is visible in lateral view). Cingular and sulcal lists are narrow. The sulcal lists extends approximately half of total cell length. It has three ribs. The midrib is located closer to the 1. (closest to the apex) than the 3. rib.Thecal plates are thick and finely areolated. The species is heterotrophic with round food vacuoloes often found in the cells.