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
                   Phylum Metamonada Grassé, 1952 [coordinate rank]
                     Subphylum Trichozoa Cavalier-Smith, 1997
                       Infraphylum Parabasalia Honigberg, 1973
                         Class Trichomonadea Kirby, 1947
                           Order Tritrichomonadida Cepicka, Hampl & Kulda, 2010 - tritrichomonadids
                             Family Dientamoebidae Grassé, 1953
                               Subfamily Protrichomonadinae Honigberg & Kuldová, 1969
                                 1 Genus Histomonas Tyzzer, 1920 [monotypic]
                                 2 Genus Parahistomonas Honigberg & Kuldová, 1969
                                 3 Genus Protrichomonasᵀ Alexeieff, 1911