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 Neidiineae D.G.Mann (1990)
           Family Scoliotropidaceae Mereschk. (1903)
             Genus Progonoia H.-J. Schrad. (1969)