Alienochelys

Alienochelys ("strange turtle") is an extinct genus of marine turtle known from Maastrichian-aged Cretaceous phosphates in Morocco. With a skull measuring 41.5 cm long, it would have been a very large turtle. It was first described as a member of the family Dermochelyidae, meaning that it is a relative of the modern leatherback turtle, though a 2018 study identifies it as a sister taxon of Ocepechelon belonging to the family Protostegidae, indicating that it may have been closer to the extinct Archelon. Unlike other sea turtles, Alienochelys ' the jaws being adapted for a powerful crushing pattern well adapted for a durophagous lifestyle, as well as its unusual cranial characteristics.