Kingdom Protoctista Hogg, 1860 Phylum Bacillariophyta Engl. & Gilg (1919) - diatoms see [unranked] Diatomea Kütz. (1844) Class Bacillariophyceae Haeckel (1878) - pennates Subclass Bacillariophycidae D.G.Mann (1990) - raphid diatoms Order Naviculales Bessey (1907) Suborder Diploneidineae D.G.Mann (1990) 1 Family Diploneidaceae D.G.Mann (1990) 2 Family Progonoiaceae see Family Scoliotropidaceae Mereschk. (1903) 3 Family Scoliotropidaceae Mereschk. (1903)