The Indo-Pacific humpback dolphin (Sousa chinensis) is a species of humpback dolphin inhabiting coastal waters of the eastern Indian and western Pacific Oceans. This species is often referred to as the Chinese white dolphin in mainland China, Macao, Hong Kong, Taiwan and Singapore as a common name. Some biologists regard the Indo-Pacific dolphin as a subspecies of the Indian Ocean humpback dolphin (S. plumbea) which ranges from East Africa to India. However, DNA testing studies have shown that the two are distinct species. A new species, the Australian humpback dolphin (S. sahulensis), was split off from S. chinensis and recognized as a distinct species in 2014. Nevertheless, there are still several unresolved issues in differentiation of the Indian Ocean-type and Indo-Pacific-type humpback dolphins.