Kingdom Chlorobiota C.Jeffrey ex Doweld (2001) - plants see Subkingdom Viridiplantae Caval.-Sm. (1981) Subkingdom Pteridobiotina Britton & A. Br. (1896) Superdivision Cycadophytanae Doweld (2001) see Superphylum Cycadophytanae Doweld (2001) Division Ginkgophyta Bessey (1907) [monotypic] see Phylum Ginkgophyta Bessey (1907) Class Ginkgoopsida Engl. (1897) Order †Karkeniales Doweld (2001) Family †Karkeniaceae Krassilov (1972) Genus †Karkenia Archangelsky (1965)