Raptors, also called dromaeosaurs, are a diverse group of predators known for stiff tails and an oversized multi-functional claw rising from the second toe on their hind feet. This claw was handy for digging, climbing and fighting, turning these diminutive dinosaurs into formidable predators. Utah formations have yielded several new species in the past two decades.
Many are believed to have been feathered and the state paleontologist likens them to "flightless protobirds" because of their close association with avian life.
Yurgovuchia could be an ancestor to the famous bear-sized Utahraptor, one of the family's largest members, according to lead author Phil Senter of North Carolina's Fayetteville State University. Dromaeosaur vertebrate come with bundles of rods that jut out and fuse the tail into one piece. These rods in Yurgovuchia and Utahraptor appear shortened, suggesting a relationship between the two, Senter said.
UGS paleontologist Don DeBlieux discovered the specimen in 2005 at Doelling's Bowl, a rich bone bed Doelling mapped northeast of Arches. The find included several elements of the vertebral column and the pelvis, said co-author Jim Kirkland, the Utah state paleontologist.
Also at this site and the nearby Andrew's Site, in the Yellow Cat element of the Cedar Mountain Formation, scientists recovered pieces of two other raptors that are believed to be new to science. All three specimens are held by the Natural History Museum of Utah.
Not enough of these specimens have been recovered to characterize them as new species, however, and UGS plans to return to these sites this summer to hunt for more pieces.
The Yurgovuch specimen is the first to emerge from Doelling's Bowl, but Kirkland believes the site conceals a trove of unknown Cretaceous life. He predicted it will yield specimens that will be the basis for characterizing as many six new dinosaur species.
"In Doelling's Bowl, everything is new," he said.
Kirkland suspects the site, located on federal land, was a swamp that trapped these specimens when they were alive and preserved their bones.
"We found a long-neck dinosaur that had been mired," he said.
Co-authors on the new study include DeBlieux, Scott Madsen, also with UGS, and Natalie Toth of the Natural History Museum of Utah.