Division Bacillariophyta Engl. & Gilg (1919) see Phylum Bacillariophyta Engl. & Gilg (1919)
Count: 3c;45o;91f;291g;308s
   Class Bacillariophyceae Haeckel (1878) - pennates
  Count: 11o;37f;115g;299s
     Subclass Bacillariophycidae D.G.Mann (1990) - raphid diatoms
    Count: [f] 10o;35f;110g;299s
       Order Surirellales D.G.Mann (1990)
      Count: [f] 3f;9g;4s
         Family Surirellaceae Kütz. (1844)
        Count: 7g;4s
           Genus Petrodictyon D.G.Mann (1990)
          Count: [*] 4s [30 Mar 2016]
             1 Petrodictyon gemmaᵀ (Ehrenb.) D.G.Mann (1990)
            Count: -
             2 Petrodictyon contiguum (A. Mann) D.G.Mann (1990)
            Count: -
             3 Petrodictyon foliatum (A. Mann) D.G.Mann (1990)
            Count: -
             4 Petrodictyon gemmoides (Østrup) D.G.Mann (1990)
            Count: -