Fossils of a recently-discovered dinosaur species in Argentina are a “missing link” in the evolution of the long-necked giants that roamed the earth millions of years ago, palaeonto-logists have said.
Long-neck, long-tail plant-eaters like Diplodocus, Brachiosaurus and Brontomerus – the largest creatures ever to have walked on earth – are dinosaurs known as sauropods. They lived some 170 million years ago.
Palaeontologists see the recently discovered Leonerasaurus Taquetransis as the connection between the smaller prosauropods – also known as near-sauropods – like Sellosaurus and Plateosaurus from the Triassic period (248-205 million years ago) to their much larger descendants, the sauropods.
Leonerasaurus lived some 10 million years before the sauropods and measured just three metres long, said Diego Pol of the Egidio Feruglio Museum of Paleontology.
“The importance of this find is that it is a new species. It gives us information on the origin of the sauropods,” Mr Pol said.
Leonerasaurus is “a very primitive species ... that helps us understand the evolutionary tree of the giants that appeared later,” Mr Pol said.
Mr Pol said he made the find along with a geologist and a student in the southern Patagonian mountains of Taquetran at a site with fossil remains from the Jurassic period (206-144 million years ago).
But the team did not find a complete Leonerasaurus. “Parts of the skull and the tail are missing, but the backbone, the hips, front and back legs are there,” Mr Pol said.
Argentina earned fame as a prime site for dinosaur fossil hunters starting in the 1980s with several discoveries, including the Argentinosaurus Huinculensis, a giant herbivore measuring more than 40 metres long that lived 98 million years ago.
Later, in 1993, scientists found remains of the Giganotosaurus Carolinii, a T-Rex-type creature that is the largest known carni-vorous dinosaur ever found.
Mr Pol is the co-author of an article announcing the Leonerasaurus discovery that appeared January in the journal Plos One.