A prehistoric "crime scene" involving a marine reptile eating one of its flying cousins before being killed by the "T-rex of the ocean" has been uncovered in outback Queensland.
The 100-million-year-old bones of an ichthyosaur, pterosaur and kronosaurus were discovered in the state's fossil-rich north-west, which was once the formidable Eromanga Sea.
University of New England associate researcher Matt White, who had a leading role in the discovery reported this week in the Gondwana Research journal, said it was one of only a handful of palaeontological finds showing an interaction between three different species.
Palentologist Dr Matt White is the lead researcher for the three fossil discovery in Richmond. (Supplied: Dr Matt White)
"It is an extraordinary find … it will attract scientists from all over the world," he said.
Dr White also said the more-than 30 bite marks could be the most recorded in any marine fossil.
Travellers Mick and Cathy Freeman stumbled upon the first of the remains — a six to seven metre ichthyosaur, affectionately named "BOB", for "bag of bones" — in 2019.
The skull of the icthyosaur being uncovered in outback Queensland. (Supplied: Matt White)
The long-extinct marine reptile was "dolphin-like" and grew up to 3 metres in length.
Dr White said the importance of the find was unknown at the time, but three years later, Kevin Petersen, then the curator of Richmond's Kronosaurus Korner museum, began unearthing the "murder scene".
"When we had a closer look at it, all the vertebrae and bones in and around the trunk region of this ichthyosaur were shattered, but they had so many tooth and bite marks in it that I hadn't seen before," Dr White said.
"We had the skull and the tail preserved, but that whole midsection was just ravaged by a large predator."
Kevin Petersen (left) worked to unearth the find with Matt White. (Supplied: Matt White)
He said there could only be one perpetrator of such violence in that time and place.
"The only one that was capable of basically ripping into a carcass like that in that area was a kronosaurus," Dr White said.
The marine reptile could grow up to 14 metres in length and had more than 100 sharp teeth that could easily tear through smaller prey.
Kronosaurus Korner museum, formerly curated by kevin Petersen. (Supplied: Paul Stumkat)
"They're quite a formidable animal — basically the T-rex of the ocean," Dr White said.
But there was even more to the "unbelievable find".
"Some of the actual ichthyosaur's stomach remains were preserved, and this is also a world-first," Dr White said.
"It had pterosaur remains in its stomach … the first documented case."
Some pterosaurs had a wingspan of up to 12 metres.
100-million-year-old cold case
Dr White said the details of precisely what had happened had to be filled in by the imagination, but the fossils painted a picture of a gruesome attack by a top ocean predator.
"[It is] a marine reptile crime scene and it did take a bit of working out to tell that story," he said.
"But did the actual kronosaurus leap out of the water and smash the ichthyosaur? Or was the ichthyosaur breaching the water and snatching a pterosaur out of mid-air to eat?
"[We just know] this is what's happened to the fossil, and what happened in the exact term of events we don't know, but that's half the exciting thing of palaeontology."
The "BOB" discovery was sectioned into blocks and transferred to the museum in Richmond. (Supplied: Matt White)
British palaeontologist Dean Lomax, who was not involved in the research, saw the discovery during a recent visit to Australia.
"It's one of the clearest examples ever discovered of a three-tier predator interaction and offers an unprecedented snapshot of behaviour in Australia's Cretaceous seas," he said.
"This extraordinary fossil records a trophic interaction between a pterosaur eaten by an ichthyosaur that was then partly consumed by a giant pliosaur.
"It gives us direct evidence of behaviour in the Eromanga Sea."
Dean Lomax recently inspected the discovery in Richmond. (Supplied: Dean Lomax)
Dr Lomax is recognised for his work studying ichthyosaurs and travelled across Queensland for a National Dinosaur Day initiative.
He said Queensland's fossil discoveries were globally significant because many species found in the region did not exist anywhere else.
