Spinosaurus was a huge semi-aquatic dinosaur from the Cretaceous, 99 to 93.5 million years ago. It was the largest of all known terrestrial carnivores.
It had paddle-like feet and nostrils on top of its crocodile-like head. This would let it submerge as a crocodile does.
The same research suggests it was larger than Tyrannosaurus rex, but more clumsy on land, moving as a quadruped. All these ideas had been suggested before. The discovery of a more complete skeleton made palaeontologists think they were correct. The fossil was found in Morocco by a private collector who let scientists examine it.
Spinosaurus bones were first discovered in Egypt in 1912 by German paleontologist Ernst Stromer in 1915. Two species, S. aegyptiacus and S. marocannus, are recognized, but there may only be one. Spinosaurus looked like Baryonyx except it was larger and more heavily built. Six specimens of Spinosaurus have been uncovered. Apparently, good material was destroyed in Munich in a 1944 bombing raid.
A note on classification: The material also supports the monophyly of the Spinosaurinae and the separation of Spinosaurus and Irritator.