This plesiosaur jaw is from a large aquatic reptile that lived during the Jurassic and Cretaceous periods. It is composed of several long and curved teeth, attached to a long and slender mandible. The teeth are extremely sharp and extend outward from the jaw in an alternating pattern. The jaw is a great example of how these ancient creatures were adapted to their marine environment. There is zero restoration on this specimen and has all original teeth embedded in this left dentary.