organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Domain eukaryotes see Domain Eukaryota Chatton, 1925
     alveolates Cavalier-Smith see [unranked] Alveolata Cavalier-Smith, 1991
       Phylum Apicomplexa Levine, 1970 see Infraphylum Apicomplexa Levine, 1970
         Class Conoidasida Levine, 1988 see Superclass Sporozoa Leuckart, 1879
           Subclass Gregarinasina Dufour, 1828
             Order Eugregarinorida Léger, 1900
               Suborder Aseptatorina Chakravarty, 1960
                 Family Monocystidae Bütschli, 1882
                   Subfamily Oligochaetocystinae Meier, 1956
                     1 Genus Oligochaetocystis Meier, 1956
                     2 Genus Echiurocystis Levine, 1977
                     3 Genus Neomonocystis Geus, 1969
                     4 Genus Acarogregarina Levine, 1977