Marine biologists have discovered a new species of dolphin swimming of the coast of northern Australia.
The dolphin is a type of humpback dolphin -- a species identified by a hump just below the dorsal fin -- but with characteristics unique enough for it to be considered a unique species.
Among the humpback dolphins, there is the Atlantic humpback and three species of Indo-Pacific humpback, one of which is the new species, according to researchers from the Wildlife Conservation Society and the American Museum of Natural History, who, along with other collaborators, published a study on the new species and the split between the Atlantic and Indo-Pacific dolphins.
The researchers used museum specimens and data gathered from beached dolphins to assess the differences in the four species by examining the dolphins' mitochondrial and nuclear DNA.
"Based on the findings of our combined morphological and genetic analyses, we can suggest that the humpback dolphin genus includes at least four member species," said Dr. Martin Mendez, sssistant firector of Wildlife Conservation Society's Latin America and the Caribbean Program and lead author of the study. "This discovery helps our understanding of the evolutionary history of this group and informs conservation policies to help safeguard each of the species."
Writing in the journal Molecular Ecology, Mendez and his colleagues report the four species of humpback dolphin as the Atlantic humpback dolphin (Sousa teuszii), which occurs in the eastern Atlantic off West Africa; the Indo-Pacific humpback dolphin (Sousa plumbea), which ranges from the central to the western Indian Ocean; another species of Indo-Pacific humpback dolphin (Sousa chinensis), which inhabits the eastern Indian and western Pacific Oceans; and the fourth Sousa species found off northern Australia. The fourth, new species has yet to be named, but the naming process is in the works, the researchers said.
"New information about distinct species across the entire range of humpback dolphins will increase the number of recognized species, and provides the needed scientific evidence for management decisions aimed at protecting their unique genetic diversity and associated important habitats," said Dr. Howard Rosenbaum, director of the Ocean Giants Program at the Wildlife Conservation Society and senior author on the paper.