Remains of the animal were found at the Isle of Skye's Bearreraig Bay, where amateur collector Brian Shawcross found them. Instead of keeping or selling them, which often happens, Shawcross donated the specimens to the Hunterian Museum in Glasgow. This allowed researchers to study them, determine their significance and piece together what this animal looked like in the flesh.
"It would have been roughly 14 feet long or so, and probably would have fed on fish and marine invertebrates," Brusatte said.
Much of Skye was under water 170 million years ago. Skye was joined to the rest of the U.K. then, and was part of a large island positioned between land masses that gradually drifted apart and became Europe and North America.
Sharks in the region during the marine reptile's lifetime were generally smaller and more primitive than today's sharks, so it's possible that Dearcmhara ate them.
As for dinos, Brusatte said, "Dinosaurs did live in other parts of Scotland at the same general time as this ichthyosaur was living in the water. We know this from other rare fossils from Skye -- bones, teeth and footprints of very different type of dinosaurs, including big long-necked sauropods and carnivorous theropods."