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 natates Cavalier-Smith, 2021
                   Clade photaria Cavalier-Smith, 2021
                     Clade eucorta Cavalier-Smith, 2021
                       Superkingdom Corticata Lankester, 1878 - corticates
                         Kingdom Chromista Caval.-Sm. (1981) - chromists
                           Subkingdom Harosa Cavalier-Smith, 2010
                             [crown] Clade Sar Adl et al. 2012 [Simpson & Dunthorn 2020]
                               Infrakingdom Halvaria Cavalier-Smith, 2010
                                 Superphylum Heterokonta Caval.-Sm. (1986)
                                   Phylum Ochrophyta Caval.-Sm. (1995)
                                     Subphylum Khakista Caval.-Sm. (2000)
                                       Diatomea Kütz. (1844)
                                         Class Coscinodiscophyceae Round & R.M. Crawford (1990) [paraphyletic] - radial centrics
                                           Subclass Coscinodiscophycidaeᵀ Round & R.M. Crawford (1990)
                                             Order Coscinodiscalesᵀ Round & R.M. Crawford (1990)
                                               Family Hemidiscaceae Hendey (1937)
                                                 1 Genus Actinocyclus Ehrenb. (1837)
                                                 2 Genus Azpeitia Perag. (1912)
                                                 3 Genus Hemidiscusᵀ G.C. Wall. (1860)
                                                 4 Genus Roperia Grunow ex Pelletan (1889)