A handful of bones, including an 8-inch (20-centimeter) claw found in the 107 million-year-old Eumeralla Formation in Australia, point to the discovery of a new species of carnivorous dinosaur. The rare find has intrigued paleontologists because the bones look almost identical to a previously-discovered species that lived around 10 million years later and thousands of miles further north.
The discovery, published in the Journal of Vertebrate Paleontology, includes two teeth, two claws, an ankle bone and a neck bone belonging to a group of theropod dinosaurs – those that include– known as the megaraptorids. The find adds to the hundreds of fossils unearthed at Eric the Red West (ERTW), a site south-west of Melbourne, Australia, but it's particularly exciting because of the resemblance to a species known as Australovenator wintonensis.
"All of these bones, other than the vertebra, can be compared with Australovenator wintonensis and all appear to be very similar," says Stephen Poropat, a paleontologist at Swinburne University and first author on the study.
The striking resemblance presents a conundrum for the researchers because Australovenator wintonensis was discovered in Queensland, a region thousands of miles to the north of ERTW. Those bones were dated to 95 million years ago, which means there's a 10 million-year gap between the two fossil finds.
"It is possible that we've found bones of subadult Australovenator individuals," says Poropat, "but it is more likely that we're dealing with a different species.
"To have a dinosaur species lasting for more than 10 million years would be extraordinary, but not impossible."
Perhaps the most impressive find is the striking 8-inch claw. Poropat explains the unique shape – one that you're probably familiar with if you've ever seen Jurassic Park – is mostly identical to megaraptorid claws found in other regions, including Megaraptor, a theropod discovered in Argentina with an almost 13-inch claw.
With only fragments of the fossil currently available, it hasn't received an official name or identifier just yet. However, Eric the Red West has turned up some stellar fossils in the past and Poropat hopes that more theropod bones will be found in the future. Another expedition to the site will occur in November.
"The deposits are all representative of deep, fairly fast-flowing rivers, so we don't expect to find a whole skeleton of a land-living animal, but we might get lucky," he says.