Spinosaurus aegyptiacus was a very large theropod. It is the largest known carnivorous dinosaur. They are related to Baryonyx and Suchomimus. Also, they probably ate fish with their crocodilian-like jaws. Their fan-like spine was probably used to regulate heat.
Originally Spinosaurus was Imagined as just your normal Theropod at the time (dragging tail, normal head, long legs) except with a giant sail. 2 specimens were found but were exploded in a 1944 bombing raid. But when baryonyx was discovered with fossils similar to Spinosaurus, it created the spinosaurus we see in Jurassic park. Then in 2014 more specimens were discovered that revealed that it had it had short legs. Some people thought that it walked on its knuckles. Then, in 2018 it was revealed that it had an amphibious tail that may have been used for swimming.