Scientists added two new members to the catalog of dinosaur species: Umoonasaurus and Opallionectes. The new species belonged to  the plesiosaur group and were described as the equivalent of today's killer whales. Umoonasaurus and Opallionectes lived 115 million years ago in the waters off Australia.

The new species were identified by a team from the University of Adelaide and the South Australian museum from fossils coming from 30 individuals who collected them from an opal mine over the past three decades.

Umoonasaurus was a Rhomaleosaurid - an ancient version of a killer whale -  and was relatively small at about 2.4 meters and had three crest-like ridges on its skull. "Imagine a compact body with four flippers, a reasonably long neck, small head and short tail much like a reptilian seal," said the researchers.