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 Hacrobia Okamoto, Chantangsi, Horák, Leander & Keeling, 2009
                             Phylum Cryptista Cavalier-Smith, 1986
                               Subphylum Rollomonadia Cavalier-Smith, 2013
                                 Superclass Cryptomonada Cavalier-Smith, 2004
                                   Class Cryptophyceaeᵀ F.E. Fritsch (1927)
                                     Genus Guillardia D.R.A. Hill & R. Wetherbee (1990) [monotypic]
                                       Guillardia thetaᵀ D.R.A. Hill & R. Wetherbee (1990)