252 to 66 million years ago

Spinosaurus - “The Sail-Backed Swimmer”

Towering above even Tyrannosaurus rex, Spinosaurus holds the title of the largest known carnivorous dinosaur. Measuring up to 15 metres long, it was a true river monster of the Cretaceous. Its long, crocodile-like snout was lined with conical teeth, perfect for gripping slippery prey like fish. Unlike most other theropods, Spinosaurus may have spent much of its time in water, making it one of the first known semi-aquatic dinosaurs. Its most striking feature was the sail-like structure rising from its back, formed by elongated spines, possibly covered in skin. Scientists still debate its purpose: was it for display, thermoregulation, or helping it glide through water like a prehistoric fin?

Spinosaurus lived in what is now North Africa, stalking riverbanks and deltas around 100 million years ago. With powerful limbs, paddle-like feet, and a tail built for swimming, it was a predator unlike any other—a true ruler of the waterways.