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 chinese white dolphins in china (including hong kong, macao and taiwan) and singapore as common name. some biologists regard the indo-pacific dolphin as a subspecies of the indian ocean humpback dolphin which ranges from east africa to india. however, dna testing studies have shown that the two are distinct species. additionally, a new species (australian humpback dolphin, "s. sahulensis") has just recently been split off from "s. chinensis" and recognized as a distinct species. nevertheless, there are still several unresolved issues in differentiation of indian-type and indo-pacific-type humpback dolphins. in fact, the taxonomic affinities of humpback dolphins in the entire bay of bengal (i.e., eastern india, sri lanka, bangladesh, and myanmar) need to be urgently re-examined. there is also still some uncertainty regarding the exact taxonomic status of populations observed in mainland malaysia and borneo. in particular, a unique subspecies ("s. c. taiwanensis") may exist in taiwan (iucn red list version 3.1).