Domain Eucaryota
   Subdomain Chlorota Doweld (2001)
     Kingdom Chlorobiota C.Jeffrey ex Doweld (2001) - plants see Subkingdom Viridiplantae Caval.-Sm. (1981)
       Subkingdom Pteridobiotina Britton & A. Br. (1896)
         Superphylum Cycadophytanae Doweld (2001)
           Phylum †Peltaspermophyta Doweld (2001) see Division Pteridospermatophyta Meyen
             Class †Dictyopteridiopsida Doweld (2001)
               Order †Lidgettoniales Doweld (2001)
                 1 Family †Lidgettoniaceae J.M.Anderson & H.M.Anderson (1985)
                 2 Family †Parthaceae Doweld (2001) [monotypic]
                 3 Family †Denkaniaceae Doweld (2001) [monotypic]