Long Neck (IMAGE) Montana State University Caption This is a skeletal reconstruction of a long-necked plesiosaur. The marine reptile known scientifically as an elasmosaur lived approximately 70 million years ago. Credit Illustration courtesy of Pat Druckenmiller Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.