There are now four species:
1. Sousa teuszii - Atlantic Humpback Dolphin
2. Sousa plumbea - Indian Ocean Humpback Dolphin
3. Sousa chinensis - Indo-pacific Humpback Dolphin
4. Sousa sahulensis - Australian Humpback Dolphin

Here is the original paper:
http://onlinelibrary.wiley.com/store...jyvf9&f81d0159


Cheers,


Nikolas