†unranked clade Pankinosternoidea Joyce et al. 2004 (turtle)
Parent taxon: Chelydroidea according to T. R. Lyson et al. 2017
See also Joyce and Bourque 2016
Sister taxon: Panchelydridae
Subtaxa: Emarginachelys Lutemys Planetochelys Tullochelys
Ecology: aquatic omnivore
Distribution:
• Eocene of United States (22: New Mexico, Wyoming collections)
• Paleocene of United States (6: Montana, Virginia)
• Cretaceous of United States (10: Montana, North Dakota, South Dakota, Utah, Wyoming)
Total: 38 collections each including a single occurrence