Juniveille Spinosaurus Tooth. Spinosaurus was among the largest of all known carnivorous dinosaurs, nearly as large as or even larger than Tyrannosaurus. Spinosaurus could reach lengths of 15–16 m (49–52 ft) and the latest estimates suggest a weight of 6.4–7.5 tonnes (7.1–8.3 short tons). The skull of Spinosaurus was long and narrow, similar to that of a modern crocodilian.