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 Pleurosigmataceae Mereschk. (1903) Genus Pleurosigma W.Sm. (1852)