Phylum Nematoda Gegenbaur, 1859 - round worms Class Secernentea Von Linstow, 1905 Subclass Tylenchia (Thorne, 1949) Inglis, 1983 Order Tylenchida G. Thorne, 1949 Suborder Tylenchinaᵀ Chitwood, 1950 Infraorder Anguinata Siddiqi, 2000 1 Superfamily Anguinoidea Nicoll, 1935 (1926)