Mosasaur Fossils. A marine reptile, the mosasaur lived 66-100 million years ago and was one of the top predators. These were collected in the gulf states in areas that were part of an inland sea during that time. $20 each for large vertebrae in upper middle, $10 each for smaller vertebrae on each end, $5 each for bottom row, 2 pieces of lower jaw in middle and 2 pieces of skull on each end. Will sell individually if desired. Please call or text Dave. Thank you!