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 Litostomatea Small & Lynn, 1981
             Subclass Trichostomatia Bütschli, 1889
               Order Vestibuliferida de Puytorac et al., 1974
                 Family Pycnotrichidae Poche, 1913
                   Genus Vestibulongum Grim, 1988