Division Bacillariophyta Engl. & Gilg (1919) see Phylum Bacillariophyta Engl. & Gilg (1919) Class Coscinodiscophyceae Round & R.M. Crawford (1990) - radial centrics Subclass Coscinodiscophycidae Round & R.M. Crawford (1990) Order Stictodiscales Round & R.M. Crawford (1990) Family Stictodiscaceae (Schütt) Simonsen (1972) Genus Stictodiscus Grev. (1861)