Trematoda Rudolphi, 1808
Achillurbaniidae
Balfouriidae
Botulidae
Brumptidae
Campululidae
Cathaemasiidae Fuhrmann, 1928
Cladorchiidae Fischoeder, 1901
Cyclocoelidae Stossich, 1902
Diplodiscidae Cohn, 1904
Echinostomatidae Looss, 1899
Fasciolidae Railliet, 1895
Gastrodiscidae Monticelli, 1892
Gastrothylacidae Monticelli, 1892
Haploporidae Nicoll, 1914
Haplosplanchnidae Poche, 1926
Heronimidae Ward, 1918
Megaperidae Manter, 1934
Mesometridae Poche, 1926
Microscaphidiidae Looss, 1900
Notocotylidae Lühe, 1909
Nudacotylidae Barker, 1916
Ommatobrephidae
Opisthotrematidae Poche, 1926
Orchipedidae Skrjabin, 1924
Paramphistomatidae
Philophthalmidae Looss, 1899
Pronocephalidae Looss, 1899
Psilostomatidae
Rhabdiopoeidae Poche, 1926
Rhabdopoeidae
Rhopaliidae Looss, 1899
Rowpaliidae
Saakotrematidae
Stephanopharyngidae Stiles & Goldberger, 1910
