Mona Lisa of dinosaurs discovered in Canada

Toronto : Scientists have discovered the world's best-preserved armoured dinosaur - dubbed as the 'Mona Lisa' of dinosaurs - in Canada that dates back about 110 million years. The new genus and species Borealopelta markmitchelli used camouflage to hide from predators despite being built like a tank, researchers said.

An analysis of the 18-foot-long specimen's exquisitely well-preserved form, complete with fully armoured skin, suggests that the nodosaur had predators, despite weighing more than 1,300 kilogrammes. The researchers came to that conclusion based on studies of the dinosaur's skin, showing that Borealopelta exhibited countershading, a common form of camouflage in which an animal's underside is lighter than its back.

The scientists say the discovery suggests that the dinosaur belonging to nodosaur family faced predation stress from meat-eating dinosaurs. "Strong predation on a massive, heavily-armoured dinosaur illustrates just how dangerous the dinosaur predators of the Cretaceous must have been," said Caleb Brown, a scientist at the Royal Tyrrell Museum in Canada.

The specimen was found by accident in 2011, by mining machine operator Shawn Funk at the Suncor Millennium Mine in Alberta. Over the last five and a half years, museum technician Mark Mitchell spent more than 7,000 hours slowly and gently removing rock from around the specimen to reveal the exceptional, fossilised dinosaur inside.

The specimen now represents the best-preserved armoured dinosaur ever found, and one of the best dinosaur specimens in the world, the researchers said. Scientists also used chemical analysis of organic compounds in the scales to infer the dinosaur's pigmentation pattern.

Those studies revealed that the dinosaur had reddish- brown-pigmented skin with countershading across its the body, researchers said. Although countershading is common, the findings come as surprise because Borealopelta's size far exceeds that of countershaded animals alive today. It suggests the dinosaur was under enough pressure from predators to select for concealment.