In the rugged outback of Queensland, a trio of amateur paleontologists has unearthed a stunning discovery. At a remote station, they stumbled upon the complete remains of a 100-million-year-old long-necked marine reptile, known as a plesiosaur—a first of its kind find in Australia.

Cassandra, the station owner, along with her fellow amateur fossil enthusiasts Sally and Cynthia, dubbed the ‘Rock Chicks,’ were the ones behind this extraordinary discovery. The fossil, likened to the Rosetta Stone of marine reptile paleontology, holds a significance akin to the ancient carved stone that deciphered Egyptian hieroglyphics upon its discovery in Egypt in 1799.

To secure this rare treasure, a team of museum paleontologists embarked on a journey to the remote site. The fossil they retrieved belonged to an elasmosaur, a type of plesiosaur that coexisted with dinosaurs. These majestic creatures once roamed the Eromanga Sea, which once covered vast areas of inland Australia between 140 and 100 million years ago.

The retrieval mission was led by Dr. Espen Knutsen, Senior Scientist at the Queensland Museum Network. He noted that these remains represent the first known head and body of an Australian elasmosaur to be held in a museum collection.

A team of museum palaeontologists travelled to the remote site to collect the fossil of the elasmosaur, a plesiosaur that lived alongside the dinosaurs

The remains are the first known head and body of an Australian elasmosaur to be held in a museum collection

‘We were extremely excited when we saw this fossil – it is like the Rosetta Stone of marine palaeontology as it may hold the key to unravelling the diversity and evolution of long-necked plesiosaurs in Cretaceous Australia,’ Dr Knutsen said.

‘We have never found a body and a head together, and this could hold the key to future research in this field.

There are well over a hundred species of plesiosaurs currently known worldwide – some had long necks and small heads, and some had short necks with giant heads.

Elasmosaurus came to the water’s surface to breathe air and had slender teeth for catching fish, crabs and molluscs.

Scientists have discovered plesiosaur fossils with stones (called gastroliths) in the stomach area, showing they swallowed them to either grind up food in their stomachs or as ballast to aid in diving.

Queensland Museum Network CEO Dr Jim Thompson said the find would help paint a comprehensive picture of Queensland’s Cretaceous marine reptiles.

‘We now hold the only head and body of an Australian elasmosaur in the world, and this significant find will contribute greatly to vital research into Queensland’s Cretaceous past,’ Dr Thompson said.

The Elasmosaurus lived in the Eromanga Sea, which covered large parts of inland Australia between 140 and 100 million years ago

‘Queensland Museum Network holds one of Australia’s most complete plesiosaur specimens, nicknamed ‘Dave the Plesiosaur’, which was discovered in 1999, however despite having 80 per cent of its bones, it was missing a head, fins and tail tips.’

Along with the new skeleton, the remains of plesiosaurs and ichthyosaurs were discovered and collected on the field trip, which will be transported to Townsville for preparation and further research.

The find is one of the biggest discovered by amateur palaeontologists the Rock Chicks, who have walked hundreds of kilometres on their quest to uncover fossils which include a plesiosaur each, a kronosaurus, an ichthyosaur and several fish and turtles.