Xenodens

Xenodens (from Greek and Latin for "strange tooth") is an extinct genus of marine lizard belonging to the mosasaur family. It currently contains a single species, X. calminechari (From Arabic کالمنشار, meaning "like a saw"), which is known from Late Maastrichtian phosphate deposits in the Ouled Abdoun Basin, Morocco. Its closest known relative is believed to be the durophagous Carinodens. Estimated to have measured around 1 m in length, both the genus and type species are named for the mosasaur's short and flattened blade-like teeth that collectively form a set of saw-like jaws. This is a feature that has never been seen in any other tetrapod but converge with the jaws of modern dogfish sharks and piranhas. Based on the feeding behavior of these animals, paleontologists believe that Xenodens used its highly specialized dentition for a broad diet on cephalopods, crustaceans, fish, and scavenged marine reptiles.