Polyptychodon

Polyptychodon is an extinct genus of sauropterygian reptile belonging to the family Pliosauridae that lived during the Cretaceous. Its fossils have been found in Europe and North America.

The type species, P. interruptus is known from Albian stage deposits from England. Greensand Formation pliosaur teeth and vertebrae from England and eastern France have long been placed within this poorly known genus. Comparison between French Albian-aged isolated vertebrae and Kronosaurus suggests a size of approximately 7 m for Polyptychodon.

One species is known from North America (P. hudsoni, holotytpe = SMM 60313). It is known from Turonian stage rocks of Dallas, Texas.