Division Bacillariophyta Engl. & Gilg (1919) see Phylum Bacillariophyta Engl. & Gilg (1919) Class Bacillariophyceae Haeckel (1878) - pennates Subclass Bacillariophycidae D.G.Mann (1990) - raphid diatoms Order Naviculales Bessey (1907) Suborder Naviculineae (Bessey) Hendey (1937) Family Plagiotropidaceae D.G.Mann (1990) Genus Pachyneis Simonsen (1974)