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 †Cycadeoideophyta T.N.Taylor (1981) [monotypic] see Class Cycadeoideopsida D.H.Scott (1923)
             1 Class †Cycadeoideopsida D.H.Scott (1923) [monotypic]