After first being classified as an eagle more than 100 years ago, a new discovery by Flinders University and South Australian Museum palaeontology experts has uncovered Australia's first vulture species; Cryptogyps lacertosus.

Vultures are birds of prey that feed almost exclusively on decaying flesh.

Lead author Dr Ellen Mather, from the Flinders University palaeontology research lab said the fossils has been kept in a collection at the Australian Museum since 1976, when they were donated, until they were "kindly" loaned to her and her colleagues for the purpose of their research.

Unfortunately, Dr Mather doesn't know what cave system the fossils were found in.

"These fossils are part of what is known as the 'Old Collection' of the Australian Museum, a large number of fossils that were collected between 1884 and 1917 when the NSW Department of Mines was responsible for the caves," she said.

"Whoever originally collected them did not leave a record of where they were found, which is very annoying for us scientists."

The Wellington fossils included two fragments of distal humeri, the end of the upper arm bone that connects to the elbow, which is identical to the original fossil from the Warburton River that the species was described on.

"This confirmed that Cryptogyps lacertosus was actually present in the fossil assemblage," she said.

This is the first time one of these scavenging raptors has been found to have lived in Australia.

More importantly, these bones allowed the researchers to connect the third fossil, a tarsus (lower leg bone in birds that connects to the foot), to the species, as it was both the right size and could be definitively ruled out as any living eagle.

"This tarsus was critical to identifying Cryptogyps as a vulture, as it has similar characteristics to other species still alive today," she said.

Finding these fossils in Wellington Caves "definitely" means the species would have resided round the Wellington area.

"In fact, evidence suggests Cryptogyps lacertosus was widespread across Australia, much like the Wedge-tailed Eagle today," she said.

"There is at least one fossil known from caves in the Nullarbor Plains of Western Australia, and the first fossil found in 1905 came from northern South Australia."

Dr Mather said it was "thrilling" to confirm the first vulture species using the fossils from Wellington Caves.

"Other palaeontologists had previously suggested that this species, originally described as an eagle, was actually a vulture," she said.

"Our research wanted to definitively determine if this was the case through rigorous comparisons and analyses.

"So to have the evidence from the Wellington Caves fossils right in front of our eyes was very exciting, and even more so when our results supported the vulture identity."

Whilst now extinct, Cryptogyps lacertosus would have existed alongside Diprotodon.

At this point in time, there isn't enough of the skeleton to know exactly what Cryptogyps lacertosus looked like, or what it ate. Gaining this information will require more discoveries in the future.