Plumbeous (Indian) humpback dolphin

Some biologists consider Humpback Dolphins in the Indo-Pacific to consist of two species: S. plumbea in the western Indian Ocean, from South Africa to at least the east coast of India, and S. chinensis, from the east coast of India to China and Australia. These two geographic forms differ markedly in their external morphology, and are moderately distinct in their skull morphometrics (see Jefferson and Van Waerebeek 2004 for a partial summary).