Metriacanthosaurus is a genus of theropod dinosaur that lived in Europe during the Middle Jurassic period, about 160 million years ago. Its name means "Moderate-spined lizard", because its back vertebrae are taller than other meat-eating dinosaurs such as "Allosaurus", but shorter than those of other meat-eating dinosaurs, such as "Acrocanthosaurus". Like most theropods, "Metriacanthosaurus" was a meat-eater. It had three fingers on each hand. Each finger ended in a sharp, hook-like claw that was used to grab prey before giving the killing bite with its jaws. It probably preyed on the large, long-necked sauropods, such as "Pelorosaurus", that lived in the same time and place as it. It was originally classified as a megalosaurid, but recent studies show that it belongs to its own family, the Metriacanthosauridae