Sundance Sea
The Sundance Sea had many types of animals. The oyster Gryphaea was very common, and shark teeth have been found. Fish, belemnites and to an extent ammonites swarmed in shoals. Crinoids and bivalvia dotted the seafloor. Ophthalmosaurus, a large ichthyosaur, swam in the seas using its large, long jaws to catch belemnite 'squid'. Pantosaurus, a plesiosaur the size of a seal, went after the easier-to-catch fish. The largest marine reptile in the Sundance Sea was Megalneusaurus, a large pliosaur similar to Liopleurodon. Its fossils have been found in Alaska and Wyoming, which were both covered by the Sundance Sea when it was alive.