previously placed in the Order: CEPHALASPIDEA, in the Subclass: OPISTHOBRANCHIA

Class : Gastropoda   Cuvier, 1797
Clade:  Heterobranchia   J.E. Gray, 1840
Infraclade:  Lower Heterobranchia (Allogastropoda)  Haszprunar, 1985
according to Bouchet & Rocroi (2005) is the superfamily: Acteonoidea no more in the Suborder Cephalaspidea

Superfamily:  Acteonoidea  d'Orbigny, 1843
Family:  Aplustridae  J.E. Gray, 1847

Micromelo undatus

Class:  Gastropoda  Cuvier, 1797
Subclass:  Heterobranchia  J.E. Gray, 1840
Clade:  Euthyneura  Spengel, 1881
Clade:  Euopisthobranchia  Jörger et al., 2010
Clade:  Cephalaspidea  P. Fischer, 1883

Superfamily:  Philinoidea  J.E. Gray, 1850
Family:  Aglajidae  Pilsbry, 1895 (1847)

Navanax gemmatus