[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 Anthocerotophyta Stotler & Crand.-Stotl. (1977) - hornworts see Subphylum Anthocerotophytina Doweld (2001)
               Class Anthocerotopsida Jancz. (1872) - hornworts
                 1 Subclass Anthocerotidae Engl. (1893) [monotypic]
                 2 Subclass Dendrocerotidae Duff, J.C. Villarreal, Cargill & Renzaglia
                 3 Subclass Notothylatidae Duff, J.C. Villarreal, Cargill & Renzaglia [monotypic]