Kingdom Protoctista Hogg, 1860 Phylum Bacillariophyta Engl. & Gilg (1919) - diatoms see [unranked] Diatomea Kütz. (1844) Class Fragilariophyceae Round (1990) - araphid, pennate diatoms see Class Bacillariophyceae Haeckel (1878) Subclass Fragilariophycidae Round (1990) - core araphid diatoms Order Fragilariales P.C.Silva (1962) Family Tabellariaceae Kütz. (1844) 1 Genus Tabellaria Ehrenb. ex Kütz. (1844) 2 Genus Tetracyclus Ralfs (1843)