Imagine a fearsome, fast and feathered prehistoric predator, a giant bulked-up ostrich-like creature that captures its prey with massive claws.
It's not a "Jurassic Park" fictional character but a dinosaur discovery, unearthed in West River, that lives up to many of the traits of Steven Spielberg's vision of long-ago raptors.
A partial skeleton of a heretofore unknown species of dinosaur, dubbed a "giant raptor," was found by a team of scientists in part of the Hell Creek Formation in southeast Harding County south of the Slim Buttes formation.
The specimen, named Dakotaraptor, is one of the largest raptors found in the world at more than 16 feet long.
Despite being pumped up in the movies, the Velociraptor is really only about the size of a turkey, but the Dakotaraptor would have towered over it, standing more than 8 feet tall and having knife-like claws almost 10 inches long.
The forearms, several vertebra, a claw and some teeth from the Dakotaraptor were found, but no skull has been recovered from the Harding County dig site.
Perhaps the most significant discovery from the fossil was the evidence of "quill knobs" on the specimen's forearms. This showed that long feathers were attached to the arm of this dinosaur, making for small wings. The discovery means the Dakotaraptor is the largest winged dinosaur ever discovered.
The specimen was found a few years ago, then thoroughly researched and last week, an article on it was published in the journal Paleontological Contributions. Team of scientists that worked on the project were led by Robert DePalma, but one of the co-authors on the paper was Peter Larson, president of the Black Hills Institute of Geological Research in Hill City.
Larson worked with the team on identification and on finding comparative examples of other raptors, figuring out how they differed from the Dakotaraptor.
The wings remain a mystery.
"We aren't sure what those wings were used for but it wouldn't have been flying; maybe it helped them move along the ground," Larson said in a phone interview on Wednesday.
The paper goes on to suggest the wings may have played a role in hunting strategy, used as a mating display or to shield their young.
He said this discovery is so important because this group of dinosaurs is "very, very closely related to birds."
This specimen could illustrate an important link between dinosaurs and the large birds still living today according to Larson. He noted that the types of "quill scars" found on Dakotaraptor also are found on other large birds living today.
Dakotaraptor lived roughly 66 million years ago in the late-Cretaceous period, near the time of the mass extinction event for dinosaurs thought to be caused by a meteor. Dakotaraptor likely died off in that mass extinction event along with three-quarters of all life on earth.
The paper goes on to talk about how the speedy and agile predator may have lived.
"This Cretaceous period raptor would have been lightly built and probably just as agile as the vicious smaller theropods, such as the velociraptor," DePalma wrote in a press release. Its long legs would have made it a fearsome predator. The paper suggested the possibility that it hunted in packs or family groups.
Where the Dakotaraptor was found is an area rich in dinosaur fossils, and not very deep underground, according to Larson. The formation ranges between 65 million to 70 million years old and was formed on a delta in a warm and moist climate.
Now that the team has published its findings, Larson said he already has found in collections other bones, previously unidentified, belonging to Dakotaraptor, including a femur.
The bones from Dakotaraptor are being held at The Palm Beach Museum of Natural History, in Fort Lauderdale, Fla. A cast replica of Dakotaraptor will be made and housed at Black Hills Institute of Geological Research in Hill City.