Coastal bottlenose dolphins from southeastern Australia are Tursiops aduncus according to sequences of the mitochondrial DNA control region

Sequence analysis of the mitochondrial DNA control region was used to clari fy the taxonomic status of two coastal bottlenose dolphin populations from southeastern Australia currently classified as Tursiops truncatus. A 368-bp segment of the control region of 57 biopsy-sampled, photo-identified dolph ins of Jervis Bay and Port Stephens was compared to published sequences of T. truncatus and T. aduncus from different oceanic regions. Sequence diverg ence between haplotypes from southeastern Australia and T. aduncus was much lower than that from T. truncatus. Analyses using two different methods of phylogenetic reconstruction unambiguously placed all haplotypes from south eastern Australia in a group composed exclusively of T. aduncus. The result s strongly indicated that these two bottlenose dolphin populations belong t o T. aduncus, extending the range of the species to subtropical waters of t he Western South Pacific Ocean.