ScienceLoch Ness Monster? No, But Dolphin-sized Reptile Terrorized Isle of Skye 170 Million Years Ago The Dearcmhara shawcrossi was a fearsome marine reptile that hunted prehistoric sharks and dinosaurs in the Middle Jurassic period. The dolphin-like animal thrived when the Isle of Skye was still under water 170 million years ago.by Rhodi Lee