Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         [crown] Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           Clade neomura Cavalier-Smith, 1987
             Domain Eukaryota Chatton, 1925 - eukaryotes
               Clade discaria Cavalier-Smith, 2021
                 Clade dorsates Cavalier-Smith, 2021
                   Clade podiates Cavalier-Smith, 2012
                     [crown] Clade Amorphea Adl et al. 2012 [Simpson, Medina & Adl 2020]
                       [crown] Clade Obazoa Brown, Sharpe, Silberman, Heiss, Lang, Simpson & Roger 2013
                         [crown] Clade Opisthokonta Cavalier-Smith 1987 [Simpson & Medina 2020] - animal-fungal clade
                           Superkingdom Holozoa Lang, O'Kelly, Nerad, Gray & Burger, 2002
                             Clade filozoa Shalchian-Tabrizi, Minge, Espelund, Orr, Ruden, Jakobsen & Cavalier-Smith, 2008
                               Kingdom Animalia Linnaeus, 1758 - animals
                                 Clade Planulozoa Wallberg, Thollesson, Farris & Jondelius 2004
                                   Subkingdom Bilateria Hatschek, 1888 - bilaterians
                                     Clade Nephrozoa Jondelius, Ruiz-Trillo, Baguñà & Riutort 2002
                                       Infrakingdom Deuterostomia Grobben, 1908
                                         [crown] Clade Ambulacraria Metschnikoff 1881 [Halanych 1995]
                                           [crown] Phylum Hemichordata Bateson, 1885 - hemichordates
                                             [crown] Class Pterobranchia Lankester, 1877 - pterobranchs
                                               Order Cephalodiscida Fowler, 1892
                                                 Family Cephalodiscidaeᵀ Schimkewitsch, 1893
                                                   Genus Cephalodiscusᵀ M'Intosh, 1882
                                                     Subgenus Cephalodiscus (Acoelothecia)
                                                     Subgenus Cephalodiscus (Cephalodiscus)ᵀ M'Intosh, 1882
                                                     Cephalodiscus evansi Ridewood
                                                     Cephalodiscus gracilis M'Intosh, 1882
                                                     Cephalodiscus nigrescens Lankester, 1905
                                                     Cephalodiscus sibogae Harmer, 1905
                                                     Subgenus Cephalodiscus (Demiothecia)
                                                     Subgenus Cephalodiscus (Idiothecia)
                                                     Subgenus Cephalodiscus (Orthoecus)