Deinosuchus was possibly the second largest crocodilian that ever lived, beaten by t
he Sarcosuchus Imperator in size. It was an Alligator that lived around 80-65 MYA. It may have grown up to 15 metres long, and lived in what is now the USA and probably Canada. It would have weighed between 5 and 10 tonnes fully grown. Deinosuchus bite marks, have been found in the skull of a Daspletosaurus - a 9-10 Metre Long Tyrannosaurid that lived a little earlier than Tyrannosaurus rex.
A Deinosuchus is briefly seen in Death of a Dynasty, where it trys to eat a Quetzalcoatlus, and fails, with the Quetzalcoatlus flying off. In the book, it actually kills it and eats it with others. However, because it has a slim snout and is said to be only 1 ton, this might have been a different prehistoric crocodile.
Deinosuchus had a major role in the final episode of Prehistoric park. It is first seen in prehistoric Texas, when it leaps out of the water, eating a Nyctosaurus. It then drags a baby Parasaurolophus into a lake, before devouoring it with other deinosuchus. Three Deinosuchus then confront a pack of Albertosaurus over a dead Parasaurolophus, and they drive the Dinosaurs away. Later on a Deinosuchus indirectly saves Nigel Marvin, by trying to eat the T.Rex chasing him, although it only slows it down.