After looking into the animal’s genetics, they confirmed it was a hybrid, which they named Steno bredanensis., The Garden Island website reported.

One of the study's authors, Robin Baird, a marine biologist with Cascadia Research Collective, based in Washington state, said his team was able to get a biopsy sample.

It is also only the third confirmed instance of a wild-born hybrid between species in the Delphinidae family.

"I think [that] just confuses the situation more than it already is," he said.

The label "wholphin" has stuck for a hybrid of a false killer whale and an Atlantic bottle-nose dolphin born at Hawaii's Sea Life Park in 1985. The hybrid named Kekaimalu still lives at the marine mammal park, where she helps teach children about genetics.

News of the hybrid seen in the wild during US Navy-funded research to study the effects of sonar, proves the "genetic diversity of the ocean", Sea Life Park curator Jeff Pawloski said.

"I always thought they were out there in the wild existing - it only makes sense," he said. "And to know she has cousins out there in the ocean is an amazing thing to know."

While some news organisation have described the melon-headed whale and rough-toothed dolphin hybrid as a new species, other things need to occur in order for that to happen, including more widespread hybridisation, Baird said.