Aristonectinae

Characters:

Ventral cheek margin weakly excavated
Pterygoids on palate closed anteriorly (lacks anterior pterygoid vacuity)
Platycoelus (flat articulation surfaces) to the vertebrae
Greater than 40 cervical vertebrae
cervical centrum length greater than height
Anterior cervical vertebrae with lateral keel

Aristonectid genera

Aristonectes
Kaiwhekea
Morturneria