Caperea marginata, pigmy right whales, are the last survivors of an aquatic family that evolved 15 million years ago but little else is known about how they behave, what they eat or how many there are in the world's oceans.

What scientists do know is that it is not a right whale at all but is instead a type of baleen whale, part of the Cetotheriidae family of whales and that it probably evolved nine million years ago. The six other species believed to make up the Cetotheriidae family have all died out.

It was recognized as having an unusual bone structure, including an arched snout, but only now has its position on the whale family tree been established.

Published in Proceedings of the Royal Society: Biological Sciences.

Mysterious whale revealed to be a 'living fossil' as member of a family that vanished from the oceans two million years ago by Lewis Smith, Daily Mail