Nemathelminthes Gegenbaur, 1859 see Phylum Nematoda Gegenbaur, 1859 Class Nematoda Gegenbaur, 1859 Subclass Penetrantia Order Dorylaimida Pearse, 1942 Suborder Dorylaimina Chitwood, 1933 Family Nygolaimidae Thorne, 1935