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 Alveolata Cavalier-Smith, 1991
                                   Phylum Miozoa Cavalier-Smith, 1987
                                     Subphylum Myzozoa Cavalier-Smith & Chao, 2004
                                       Infraphylum Apicomplexa Levine, 1970
                                         Superclass Sporozoa Leuckart, 1879
                                           Class Gregarinomorphea Grassé, 1953
                                             Subclass Orthogregarinia Cavalier-Smith, 2014
                                               Order Arthrogregarida Cavalier-Smith, 2014
                                                 Suborder Terragregarina Cavalier-Smith, 2014
                                                   Superfamily Actinocephaloidea Léger, 1892
                                                     Family Monocystidae Bütschli, 1882
                                                       Subfamily Oligochaetocystinae Meier, 1956
                                                         1 Genus Oligochaetocystisᵀ Meier, 1956
                                                         2 Genus Echiurocystis Levine, 1977
                                                         3 Genus Neomonocystis Geus, 1969 [monotypic]
                                                         4 Genus Acarogregarina Levine, 1977 [monotypic]