New Velociraptor cousin was a '4-winged' dragon that hunted prey from the trees of ancient China, fossil find hints

A newly discovered feathered dinosaur with four wing-like limbs may have prowled the lakeside forests of what is now northwestern China, gliding between trees like a flying squirrel and snatching some of the earliest birds out of the Cretaceous sky.

The predator, named Jian changmaensis, was a close cousin of Velociraptor and belonged to a strange group of small birdlike dinosaurs called microraptors. Unlike the large and scaly "Jurassic Park" version of raptors, these animals were feathered, lightweight and glided to get around. Based on fossil evidence, J. changmaensis had long feathers on both its arms and legs, giving it the look of a tiny dragon with four wings.

The fossil, described Thursday (June 4) in the journal Annals of Carnegie Museum, is only a partial left shoulder and forelimb. But those bones were enough to reveal a new dinosaur species, and possibly solve a longstanding mystery at China’s Changma Basin, a site packed with ancient bird fossils and broken bird bones that look a lot like the pellets coughed up by modern owls.

"Our team has recovered more than one hundred bird fossils at Changma, but only this single non-avian dinosaur specimen," study co-author Matthew Lamanna, a senior dinosaur researcher and curator of vertebrate paleontology at the Carnegie Museum of Natural History in Pittsburgh, in a statement.

"[Microraptors] provide a window into what the closest ancestors of the first birds were probably like," he told Live Science via email. "Studying them yields clues as to how birds got their start and how they learned to fly."

Finding a fossil among the fragments

Paleontologists uncovered the fossil in the Lower Cretaceous Xiagou formation near Changma village in the Gansu province. The rocks there were formed during the early Cretaceous period about 124 million to 120 millions ago, when the region held a large lake teeming with birds, fish, turtles and other ancient animals.

The site is famous for fossils of Gansus yumenesis, one of the first Mesozoic birds ever found in China. Since 2002, researchers have recovered more than 100 partial bird skeletons from Changma, including fossils with preserved soft tissue such as feathers, skin and claw sheaths.

"Our subsequent expeditions throughout the rest of the 2000s and into the 2010s established Changma as one of the world's most important fossil bird localities, Lamanna said. "It was an amazing thing to be a part of."

But until now, no one had found a non-avian dinosaur fossil from the basin.

That's what made J. changmaensis stand out. Amidst the fossil fragments, the specimen consisted of a fused shoulder blade, upper arm, radius and ulna. It was preserved in three dimensions, unlike many flattened microraptor fossils from the same area.

"Jian is one of the biggest microraptor specimens that has ever been found," Jingmai O’Connor, the associate curator of fossil reptiles at the Field Museum in Chicago and co-author of the study, said in the statement. "The piece of its upper arm bone that we have is about 4 inches [10 centimeters] long, so the entire dinosaur probably had something like a four-foot [1.2 meter] wingspan, around the size of a barn owl."

Microraptors were not birds. But they were very close relatives of the dinosaur lineage that gave rise to birds. Their bodies have elements that seem to blur the line between bird and dinosaur, including claws, sickle-shaped raptor feet and feathers.

"This is neat, a new fossil of those dinosaurs that were basically on the cusp of becoming true birds," Steve Brusatte, a professor of paleontology and evolution at Scotland’s University of Edinburgh who was not involved in the study, told CNN.

The bird hunter

The Changma Basin may have been a buffet for a tree-climbing predator like J. changmaensis. The site was dominated by early birds, as is evidenced by the many pellet-like remains, possibly the dinner remains of the newfound microraptor species.

Researchers can't prove that Jian made those pellets. But it is the only non-bird body fossil found at Changma so far. Jian was also a carnivore, and was much larger than the birds preserved there.

Other microraptor fossils support the idea that these dinosaurs ate from a wide menu. Previous fossilised specimens have been found with remains of fish, lizards, mammals and birds in their guts, suggesting microraptors were opportunistic hunters rather than picky specialists.

For J. changmaensis, birds may have been especially easy targets. If the dinosaur lived partly in trees and could glide, it may have ambushed early birds from branches or moved through the canopy like a sugar glider, according to the researchers.

"We don’t have very much of Jian, just some bones from the shoulder and forelimb," Lamanna said. "It's enough to know that there was this interesting new microraptor living 120 million years ago in what's now northwestern China, but not enough to be able to learn everything we'd like to learn about these dinosaurs. Maybe one of your readers will eventually become a paleontologist and be the one who finds the rest of Jian."