Nematoda
Ancyracanthidae
Anguillulidae
Aphelenchida
Ascaridida
Camallanida
Diplogasterida
Oxyurida
Rhabditida Chitwood, 1933
Spirurida Chitwood, 1933
Stephanofilariidae
Strongylida Molin, 1861
Trichonematidae
Tylenchida