In Rare Find, Scientists Unearth Fossil of Large Marine Reptile With Both Head and Body

Skeletons of elasmosaurs are often found without their skull

The skull of an elasmosaur
The skull of an elasmosaur found in Queensland, Australia Queensland Museum via CNN

A group of amateur fossil hunters in Australia have discovered the country’s first elasmosaur—an ancient long-necked marine reptile—with its head still connected to its body. The animal is believed to be a juvenile around 100 million years old, and it was excavated by paleontologists from the Queensland Museum Network. 

"We were extremely excited when we saw this fossil—it is like the Rosetta Stone of marine paleontology as it may hold the key to unraveling the diversity and evolution of long-necked plesiosaurs in Cretaceous Australia," Museum of Tropical Queensland senior curator of paleontology Espen Knutsen says in a statement.  "We have never found a body and a head together and this could hold the key to future research in this field.” 

Cassandra Prince, a member of the so-called “Rock Chicks,” found the bones while searching her on ranch in western Queensland, writes Joe Hinchliffe for the Guardian

“I’m like, no, you know, this is not real,” Prince tells the publication. “And then I look down again and I’m like, holy hell, I think that’s a skull looking up at me.”

The animal was named “Little Prince” in her honor. 

Elasmosaurs were part of a group of marine reptiles called plesiosaurs that swam in the ocean hundreds of millions of years ago, coexisting alongside dinosaurs. During the Cretaceous period (between 145.5 and 65.5 million years ago), a vast, shallow sea covered what’s now arid land in Queensland, Australia. This water was home to a variety of marine reptiles, including plesiosaurs and ichthyosaurs. Fossil discoveries are common in the area, per Moira Ritter of the News Tribune

With long necks, flippers, a tiny tail and a large body, elasmosaurs were “such bizarre animals," Queensland Museum palaeontological research assistant Christina Chiotakis tells Rachael Merritt of the Australian Broadcasting Corporation (ABC). Their bodies could reach a length of about 43 feet, though Little Prince was smaller, measuring about 20 feet.

When these animals died, their bodies swelled with gas and rose to the surface of the ocean,  where scavengers would eat away at them, often disconnecting their heads from their bodies, writes Kathleen Magramo for CNN. Even once the gas dissipated, their long necks meant the two parts were unlikely to sink to the same spot, per the Guardian

"Very, very rarely you'll find a body and head together,” Museum of Tropical Queensland senior curator of paleontology Espen Knutsen tells the ABC. "Because the head is so far away from the body at the end of this little neck, that's one of the first things that gets disarticulated from the rest of the skeleton."

Knutsen theorizes the newly discovered elasmosaur—which is missing the back half of its body—may have been chomped by a kronosaur, and the puncture could have caused the animal to quickly sink to the bottom, he tells the publication. Knutsen says the research team plans to CT scan the creature’s head and look at the chemistry of its teeth to see if they can determine more about the animal’s diet and habitat, per CNN. 

"Putting all these pieces together tells a really fantastic story of how the Earth has evolved,” Queensland Museum Network chief executive Jim Thompson tells the ABC. "That gives us a lot of ability to understand the biodynamics of these types of animals, how they move, what sort of environments they need to be in and how a skeleton is put together."