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 Bacillariales Hendey (1937) Family Bacillariaceae Ehrenb. (1831) Genus Gomphotheca Hendey & P.A. Sims (1982)