An order of big, extinct, marine reptiles, based in the Cretaceous rocks, especially in America. These people were serpentlike in form as well as in having loosely articulated and dilatable jaws, with large recurved teeth, however they had paddlelike feet. A few of them had been over fifty legs long. These are typically, basically, fossil ocean serpents with paddles. Known as also Pythonomarpha, and Mosasauria.
a team of remarkably long-bodied marine reptiles, from Cretaceous stones of Europe and The united states.