Kingdom Chlorobiota C.Jeffrey ex Doweld (2001) - plants see Subkingdom Viridiplantae Caval.-Sm. (1981)
   Subkingdom Pteridobiotina Britton & A. Br. (1896)
     Superdivision Cycadophytanae Doweld (2001) see Superphylum Cycadophytanae Doweld (2001)
       Division †Pteridospermatophyta Meyen
         Class †Lyginopteridopsida Novák (1961)
           Order †Hexapterospermales Doweld (2001)
             Family †Hexapterospermaceae Doweld (2001), nom. cons. prop.
               Genus †Potoniea Zeiller (1899)