Metriacanthosaurus is a genus of metriacanthosaurid dinosaur from England, dating to the Jurassic period, about 160 million years ago Metriacanthosaurus, meaning "moderately-spined lizard", was named for its spinous processes. Metriacanthosaurus reaches eight meters length and its weight exceeds a ton. Metriacanthosaurus had a fairly typical structure for medium-sized theropods, with a large head with sharp serrated teeth. Metriacanthosaurus was named for the height of its neural spines, which are actually not overly tall for theropods. Neural spines of Metriacanthosaurus are similar to similar spines of some other distant relatives, in particular Megalosaurus. The four legs were quite small, and each of the three fingers had a medium-sized claw. Despite its rather large size, it, thanks to its strong and clawed legs, could speed up to 30 km/h. This predator hunted large herbivorous dinosaurs in forested areas, which suggests that Metriacanthosaurus attacked prey, setting up an ambush, as a much larger tyrannosaurus.