Hi all,   First off, this is not my fossil (though I own a large crow of similar morphology), but one I recently bumped into and found particularly curious. Why? Because it's morphology seems to contradict itself. Described as a Polyptychodon interuptus (no longer considered a valid genus; Madzia [2016]) from the Late Jurassic Volga Beds (?) of Stary Oskol, the tooth appears to have enamel folds consistent with what one might expect from an ophthalmosaurid ichthyosaur, such as Platypte