Sentence:  Two species of <WSD>crocodile</WSD> inhabit Australian waterways: (a) the saltwater <WSD>Crocodile</WSD> — "Crocodylus porosus", and (b) the freshwater <WSD>crocodile</WSD> — "Crocodylus johnstoni". 
Meaning of the word marked with <WSD> tags:  Any of the predatory amphibious reptiles of the family Crocodylidae;  a crocodilian, any species of the order Crocodilia, which also includes the alligators, caimans and gavials.