Class: Reptilia
Order: Crocodilia
Family: Gavialidae
Genus: Gavialis
Species: G. gangeticus

Are an endangered species of crocodile most noted for have a long slender jaw. This is probably evolved as a way of more effectively catching fish as it's prey.  

Native to the Indian subcontinent and also called gavial, this crocodile shows the only obvious visual difference between males and females is that the male has a bulb on its nose. Other crocodiles often show size differences between the sexes though. 


A male gavial in captivity. image: wikipedia