living organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Eukaryotae see Domain Eukaryota Chatton, 1925
     Kingdom Animalia Linnaeus, 1758 - animals
       Subkingdom Eumetazoa Butschli, 1910 see [unranked] Eumetazoa Bütschli, 1910
         Phylum Platyhelminthes Gegenbaur, 1859 - flatworms
           Class Trematoda Rudolphi, 1808 - flukes see Infraclass Trematoda Rudolphi, 1808
             Subclass Digenea Carus, 1863
               Order Echinostomida LaRue, 1957
                 Suborder Echinostomata Szidat, 1939
                   Superfamily Echinostomatoidea Looss, 1902
                     Family Cathaemasiidae Fuhrmann, 1928
                       1 Genus Cathaemasia Looss, 1899
                       2 Genus Liliatrema Gubanov, 1953
                       3 Genus Reesella Mettrick, 1956
                       4 Genus Pulchrosoma
                       5 Genus Cathaemasioides Teixeira de Freitas, 1941