Domain Eucaryota Subdomain Chlorota Doweld (2001) Kingdom Bacillariobiota Doweld (2001) Subkingdom Bacillariobiotina Doweld (2001) Phylum Bacillariophyta Engl. & Gilg (1919) - diatoms see [unranked] Diatomea Kütz. (1844) Class Fragilariophyceae Round (1990) - araphid, pennate diatoms see Class Bacillariophyceae Haeckel (1878)