The 5 foot skull of Purussaurus the giant nettosuchid caiman of the Miocene epoch from the Amazon system. One of the largest ever crocodiles
Studies on the snout morphology of crocodylians points to 5 recurrent skull types repeatedly evolving their midst: 1) The generalized skull type as seen in Crocodylus niloticus the Nile crocodile. 2) Blunt-nosed skull as seen in Osteolamus tetrapsis the African dwarf crocodile. 3) The long-slender snouted crocodile as seen in gharial and Tomistoma the false gharial. 4) The deep skull with laterally compressed knife-like serrated teeth (ziphodont) as seen in the pristichampsines. 5) The duck-faced crocodiles, like Purussaurus and Mourasuchus, which have broad long duck-bill like snout and eyes placed in posterior end of the long skull. These skulls may be deep as in Purussaurus or very flat as in Mourasuchus.