Marine and Freshwater Research Marine and Freshwater Research Society
Advances in the aquatic sciences

Phylogenetic analysis of mtDNA sequences suggests revision of humpback dolphin (Sousa spp.) taxonomy is needed

Céline H. Frère A E , Peter T. Hale B , Lindsay Porter C , Victor G. Cockcroft D and Merel L. Dalebout A

A School of Biological, Earth and Ecological Sciences, University of New South Wales, Sydney, NSW 2052, Australia.

B School of Integrative Biology, University of Queensland, Brisbane, Qld 4072, Australia.

C Worldwide Fund for Nature, 1 Tramway Path, Central, Hong Kong.

D Centre for Dolphin Studies, PO Box 1856, Plettenberg Bay, South Africa 6600.

E Corresponding author. Email:

Marine and Freshwater Research 59(3) 259-268
Submitted: 25 June 2007  Accepted: 3 March 2008   Published: 30 April 2008


Humpback dolphins (Sousa spp.) have a wide distribution in the tropical Atlantic and Indo-Pacific Oceans and a confused taxonomy. Morphological assessments suggest three species groupings – Sousa teuszii (eastern Atlantic), Sousa plumbea (western Indo-Pacific), and Sousa chinensis (eastern Indo-Pacific) – but most taxonomies recognise only two species – S. chinensis (Indo-Pacific), and S. teuszii (Atlantic). To investigate phylogenetic relationships, mitochondrial DNA control region sequences (338 base pairs) from 72 Sousa representing three populations in the Indo-Pacific (South Africa: S. plumbea, n = 23; China: S. chinensis, n = 19; and Australia: S. chinensis, n = 28), and S. teuszii in the Atlantic (Mauritania, n = 2) were generated. All three Indo-Pacific populations formed robust, monophyletic clades with high bootstrap (BS) and Bayesian posterior probability (BPP) scores. Surprisingly, humpback dolphins from South Africa and China formed a strongly-supported clade with the Atlantic S. teuszii (BS 63%, BPP 0.92) to the exclusion of animals from Australia. Genetic divergence between animals from China and Australia (DA = 8.4% ± 2.47%) was greater than between China and South Africa (DA = 5.1% ± 1.80%). These results strongly suggest that Australian humpback dolphins are not S. chinensis but may represent a distinct species in their own right.

Additional keywords: Australia, Delphininae, Hong Kong, phylogeography, South Africa, speciation.


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