Ophthalmosaurus was a medium-sized ichthyosaur that lived during the Late Jurassic period, around 165 to 150 million years ago. Measuring about 6 meters (20 feet) in length, it was characterized by its large eyes, which were among the largest of any vertebrate, adapted for excellent vision in low-light conditions, likely aiding in hunting deep underwater. Ophthalmosaurus had a streamlined, dolphin-like body with a long, pointed snout filled with conical teeth, indicating it primarily fed on fish and squid. Fossils of Ophthalmosaurus have been found in Europe and North America, providing significant insights into the diversity and adaptations of marine reptiles in the Jurassic seas.