A fossilised dinosaur egg and embryo found in China belong to a previously unknown species of dinosaur that had ringed nests as large as monster-truck tyres, according to a new study.
Named Beibeilong, or “baby dragon” in English, the species belongs to a group of giant bird-like dinosaurs called oviraptors that lived during the Cretaceous Period, 90 million years ago.
Beibeilong is the largest known nesting dinosaur ever discovered, report a team led by Hanyong Pu from Henan Geological Museum and Darla Zelenitsky from the University of Calgary. Zelenitsky says the creature would have looked “a lot like an overgrown cassowary”.
Writing in Nature Communications, the scientists estimate a fully grown Beibeilong would have stretched eight metres and weighed a whopping three tonnes.
About half a metre in length, the egg was too large to have come from any known species of oviraptor.
The fossil is startlingly well-preserved as the embryo died while hatching, leaving remnants of tiny bones in the rock. The entire nest must have been buried in the later stages of incubation, the scientists suggest, as two or three eggs found at the same site also contained skeletal remains.
The egg-and-embryo fossil was first dug up by a farmer in China’s Henan Province during the early 1990s. At the time Henan was a hot spot for excavating fossilised dinosaur eggs, many of which were sold in rock and gem shows or markets, and some prepared overseas to expose well-preserved embryos.
Illegally exported to the US by fossil dealers, the Beibeilong egg caused a stir, making the cover of National Geographic magazine in 1996. In 2013 it was given back to China. Scientists investigated its excavation site and found fragments of eggs seeming to come from the same nest, allowing the scientists to properly study and describe the fossil. “Thanks to this fossil,” Zelenitsky says, “we now know that these eggs were laid by a gigantic oviraptorosaur.”