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 Ciliophora Doflein, 1901 - ciliates
         Subphylum Intramacronucleata Lynn, 1996 - amphiesmates
           Class Oligohymenophorea de Puytorac et al., 1974 - oligohymenophoreans
             Subclass Apostomatia Chatton & Lwoff, 1928
               Order Astomatophorida Jankowski, 1966
                 Family Opalinopsidae Hartog, 1906
                   1 Genus Chromidina Gonder, 1905