Division Bacillariophyta Engl. & Gilg (1919) see Phylum Bacillariophyta Engl. & Gilg (1919)
   Class Fragilariophyceae Round (1990) - araphid, pennate diatoms see Class Bacillariophyceae Haeckel (1878)
     Subclass Fragilariophycidae Round (1990) - core araphid diatoms
       01 Order Fragilariales P.C.Silva (1962)
       02 Order Tabellariales Round (1990)
       03 Order Licmophorales Round (1990)
       04 Order Rhaphoneidales Round (1990)
       05 Order Ardissoneales Round (1990)
       06 Order Toxariales Round (1990)
       07 Order Thalassionematales Round (1990)
       08 Order Rhabdonematales Round & R.M. Crawford (1990)
       09 Order Striatellales Round (1990)
       10 Order Cyclophorales Round & R.M. Crawford (1990)
       11 Order Climacospheniales Round (1990)
       12 Order Protoraphidales Round (1990) see Order Protoraphidales Round ex Gogorev (2015)