[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 Polypodiophytina Reveal (1996) [monotypic]
                 Class Polypodiopsida Cronquist, Takht. & Zimmerm. (1966) - ferns
                   1 Subclass Equisetidae Warm. (1883) [monotypic]
                   2 Subclass Marattiidae Klinge (1882) [monotypic]
                   3 Subclass Ophioglossidae Klinge (1882)
                   4 Subclass Polypodiidae Cronquist, Takht. & Zimmerm. (1966)