Deinosuchus

Deinosuchus is a huge crocodilian found only in fossilized form. A 1954 find noted that the lower jaw was probably 1800mm (six feet)in length, and giving the full length of the animal as probably about 50 feet (15 meters). It was at first known as Phobosuchus, but later the name stabilized as deinosuchus. In his preface, David Schwimmer notes that the characteristics such as snout constriction that identify a modern animal as a crocodile and not an alligator should not be applied, so that this animal should only be termed crocodilian.

Anatomy
Fossils of Deinosuchus can sometimes be confused with fossil remains of a marine crocodile known as Thoracosaurus.