By Thomas A. Jefferson and Patricia Rosel
The Society for Marine Mammalogy’s Committee on Taxonomy publishes a list of marine mammal species of the world and updates it annually. Recent revisions include many changes at the subspecies level, but here we summarize only species- or genus-level changes. A ‘new’ whale (actually not new, but a resurrected species), Mesoplodon hotaula, has been added to the list. The humpback dolphin genus Sousa has been split from two species into four, including the resurrection of S. plumbea (Indian Ocean humpback dolphin), and the addition of a new species, S. sahulensis (Australian humpback dolphin). Perhaps the most interesting change for many marine mammalogists is the dropping of Delphinus capensis as a recognized species and the resultant lumping of all common dolphins of the world back into the single species D. delphis. This can be viewed as a provisional change, as work is underway to determine if the eastern North Pacific long-beaked common dolphin, qualifies as a distinct species (or only as a subspecies as it is currently listed).
Some recently proposed species are not on the current list, mostly due to conflicting evidence or the lack of strong evidence for their distinctiveness at the species level. These include Inia boliviensis, Inia araguaiaensis, and Tursiops australis. Future work may clarify the status of each of these. Finally, while it is recognized that several genera of dolphins are paraphyletic or polyphyletic, and thus not good phylogenetic taxa, no taxonomic changes will be made to the list until further work can clarify how best to deal with these ‘problematic’ genera – Lagenorhynchus, Stenella, and Tursiops.
For more details, consult the latest version of the list at: https://www.marinemammalscience.org/species-information/list-marine-mammal-species-subspecies/. Thanks to Bill Perrin for his many years of service as Taxonomy Committee chair. Patty Rosel will be taking over from Bill as the new chair.