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 Cycadophyta Bessey (1907) see Subclass Cycadidae Pax (1894)
             Class †Pachytestopsida Doweld (2001)
               Order †Pachytestales Doweld (2001)
                 Family †Pachytestaceae Doweld (2001), nom. cons. prop.
                   Genus †Pachytesta Brongn. (1874)