De orde Nemaliales F.Schmitz kent 6 families.
| Galaxauraceae P.G.Parkinson | Liagoropsidaceae S.-M.Lin, Rodríguez-Prieto & Huisman | Scinaiaceae Huisman, J.T.Harper & G.W.Saunders |
| Liagoraceae Kützing | Nemaliaceae (Farlow) De Toni & Levi | Yamadaellaceae S.-M.Lin, Rodríguez-Prieto & Huisman |
