Secernentea
Acuariidae (Railliet, Henry & Sisoff, 1912)
Anguillicolidae Yamaguti, 1935
Cystidicolidae (Skrjabin, 1946)
Desmidocercidae Cram, 1927
Dichelyne Jägerskiöld, 1902
Diplotriaenidae
Filarioidea Maggenti, 1982
Gnathostomatidae Railliet, 1895
Gongylonematidae
Guyanemidae Petter, 1975
Habronematidae
Hartertiidae
Hedruridae
Physalopteridae (Railliet, 1893)
Pneumospiruridae
Rhabdochonidae (Travassos, Artigas & Pereira, 1928 subfam.) Skrjabin, 1946
Rictulariidae
Spirocercidae
Spiruridae
Tetrameridae Travassos, 1914
Thelaziidae Skrjabin, 1915
