[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 Order Cycadales Pers. ex Bercht. & J.Presl (1820) - cycads