Details

Autor(en) / Beteiligte

• Costa, A. P. B.
• Archer, F. I.
• Rosel, P. E.
• Perrin, W. F.

Titel

Tursiops truncatus nuuanu, a new subspecies of the common bottlenose dolphin from the eastern tropical Pacific

Ist Teil von

• Journal of mammalian evolution, 2023-03, Vol.30 (1), p.213-229

Ort / Verlag

New York: Springer US

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• In the eastern Pacific Ocean, three distinct forms of common bottlenose dolphin ( Tursiops truncatus ) have been identified, with suggestions they may be different species: a southern California/Mexico coastal, a northern temperate offshore, and an eastern tropical Pacific (ETP) offshore form. Currently, only one species ( T. truncatus ) is recognized in the region, with the first two forms described as distinct ecotypes. The goal of this study was to improve our understanding of the taxonomic status of these previously described forms through a re-examination of their morphological differentiation. We analyzed 135 skulls from the eastern and western Pacific, including the two nominal species, T. gillii and T. nuuanu , previously described for the eastern North Pacific and ETP, respectively. Additionally, we examined the holotypes of two currently recognized species in the genus, T. truncatus and T. aduncus . Our results showed significant morphological differentiation among bottlenose dolphins in the Pacific Ocean. The ETP offshore bottlenose dolphins were smaller in skull and body size and diagnostically distinct from dolphins in the western North Pacific and other regions in the eastern Pacific. Our results also indicated that, while other bottlenose dolphins in the Pacific were more similar to the globally distributed T. truncatus , the ETP offshore dolphins shared similarities with a previously described species in that region. The distinct environmental conditions in the ETP may be driving the evolutionary differentiation of these bottlenose dolphins. Given these results, we here recommend the recognition of ETP offshore bottlenose dolphins as a distinct subspecies, Tursiops truncatus nuuanu .