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 Coscinodiscales Round & R.M. Crawford (1990) Family Heliopeltaceae H.L. Sm. (1872) Genus Actinoptychus Ehrenb. (1839)