‘Chicken from Hell’ — an ‘unusual’ ancient species — once roamed the Midwest, study says

Millions of years ago, a bird-like dinosaur, known as the “chicken from Hell,” roamed the North American continent. Weighing around 170 pounds, it sported a toothless beak and was blanketed by a layer of feathers.

The previously unknown prehistoric creature was recently identified using fossilized bones found in South Dakota, according to a study published Jan. 24 in the journal PLOS One.

The bones, including a femur and tibia, were discovered in Meade County, which makes up part of the Hell Creek Formation, a swath of sedimentary rock littered with the remains of old plant and animal life.

While studying the bones, Oklahoma State University researchers initially thought they might belong to a larger dinosaur called Anzu wyliei. However, histology tests revealed they had stumbled upon a brand new species.

The newfound creature is a caenagnathid, which belongs to the oviraptorosaur family, a group of human-sized theropods with slender limbs and grasping hands.

Characterized by their “unusual” skulls, they were found throughout North America and Asia during the Late Cretaceous period, which lasted from about 100 to 66 million years ago.

The new species was named Eoneophron infernalis, which translates to “Pharaoh’s dawn chicken from hell.”

It had three-fingered hands with sharp claws as well as a short tail, unlike modern birds, Kyle Atkins-Weltman, one of the study authors, told McClatchy News.

Its diet is difficult to determine, Atkins-Weltman said. Oviraptorosaur species were both herbivorous and omnivorous, and without teeth, it’s hard to say which camp the newfound species fell into.

“I’d make an educated guess that they were omnivores, with different species possibly leaning more towards carnivory or herbivory,” Atkins-Weltman said.

The creature’s social behavior is also difficult to establish — particularly because few caenagnathid fossils have been found.

“It’s likely that, just like in modern animals, the sociality (or lack thereof) differed between species, with some being solitary while others lived in flocks,” Atkins-Weltman said.

The study indicates that caenagnathids flourished throughout the Late Cretaceous before being snuffed out 66 millions years during a mass extinction event caused by an asteroid impact.

“Right now we’re just scratching the tip of the iceberg with this group, and there is a lot of opportunity for future research,” Atkins-Weltman said. “Raising awareness and garnering enthusiasm for these little ‘hell chickens’ will hopefully inspire folks out in the field to not overlook small dinosaurs.”

This story was originally published January 25, 2024 at 5:39 PM with the headline "‘Chicken from Hell’ — an ‘unusual’ ancient species — once roamed the Midwest, study says."