Presented here on the original matrix as it was found, is an incredibly uncommon species of sawfish tooth. The Onchosaurus are almost never seen in the phosphate deposits near Khourigba, let alone very many sawfish fossils for that matter, the few that are found are commonly mistaken for Otodus shark remains. These sawﬁshes are so rare they are only known by isolated vertebra and rostral spines. On the basis of fossil findings they are considered large, bottom-dwelling fishes, mainly inhabiting shallow marine habitats, but they were also powerful swimmers.
This specimen comes from the Upper Cretaceous, Maastrichtian Stage, roughly 72 - 66 million years old.