New Delhi, June 30 -- Scientists have stumbled on a rare dinosaur fossil from Antarctica, tucked away for decades in a drawer.

The bone comes from the tail of a long-necked, plant-eating dinosaur called a titanosaur. Scientists haven't yet identified the species it belongs to.

It was discovered in 1985 during an expedition to Antarctica's James Ross Island and collected by geologist Mike Thomson. Working with the British Antarctic Survey, Thomson was mapping the area's rock layers and collected marine reptile fossils to help with future dating efforts. He recorded the find as a large reptile.

Decades later, paleontologist Mark Evans spotted the bone in the British Antarctic Survey's collections and wondered whether it might be a dinosa...