[living organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Eukaryota Whittaker & Margulis, 1978 see Domain Eukaryota Chatton, 1925
     Kingdom Plantae Haeckel (1866) - plants
       Subkingdom Viridiplantae Caval.-Sm. (1981) - green plants
         Infrakingdom Streptophyta Caval.-Sm. (1993)
           Superphylum Embryophyta Engl. (1887) - land plants see Clade Embryophyta Engler 1887 [Mishler & Qiu 2020]
             Phylum Tracheophyta Sinnott ex Caval.-Sm. (1998) - vascular plants
               Subphylum Spermatophytina Caval.-Sm. (1998) - seed plants
                 Superclass "Gymnospermae"
                   Class Cycadopsida Brongn. (1843) [monotypic]
                     Subclass Cycadidae Pax (1894) [monotypic] - cycads
                       1 Order Cycadales Pers. ex Bercht. & J.Presl (1820) - cycads