Aldrovandia gracilis a genus of Aldrovandia in the Halosauridae family (deep-sea eel-shaped fishes), within the Notacanthiformes order, and under the Actinopterygii class.
Genus: Aldrovandia Halosauridae Family: Order: Notacanthiformes Class: Actinopterygii Halosaurs are eel-shaped fishes found only at great ocean depths. 
