A new ankylosaur found in Utah had a surprisingly bumpy head

This species of armored dino looked more like its Asian ancestors

Akainacephalus johnsoni illustration

CRETACEOUS CRITTER  Meet Akainacephalus johnsoni, a newly discovered armored dinosaur species that roamed Utah more than 70 million years ago.

Andrey Atuchin/DMNS

A newly identified dinosaur’s evolutionary origins are written all over its face.

Bony knobs studding the head and snout of Akainacephalus johnsoni, a type of armored dinosaur called an ankylosaurid, are similar to those of Asian ankylosaurids. That was a surprise, says Jelle Wiersma, a paleontologist at James Cook University in Townsville, Australia. He and Randall Irmis, a paleontologist at the Natural History Museum of Utah in Salt Lake City, had expected the 76-million-year-old skeleton, unearthed in 2008 in Utah’s Grand Staircase-Escalante National Monument, to have a smoother dome typical of North American ankylosaurids.

These armored dinos first appeared in Asia around 125 million years ago and had reached western North America by about 77 million years ago. One other known North American ankylosaurid, a different species found in New Mexico that’s 3 million years younger than the newfound dino, also has a rugged noggin comparable to A. johnsoni’s. The new find adds to evidence that at least two types of  ankylosaurids migrated from Asia to North America during the late Cretaceous, possibly via a land bridge between the continents, the researchers report July 19 in PeerJ.

Along with a complete skull, paleontologists uncovered an intact tail club, as well as many vertebrae, limb bones and bony plates. A. johnsoni is the most complete ankylosaurid fossil yet found in the southwestern United States, the researchers say.

Akainacephalus johnsoni skull
CROWN OF THORNS Akainacephalus is derived from the Greek words for “thorn” and “head,” while johnsoni honors a museum volunteer who carefully removed rock from the fossilized skull. Phase 2 Productions

Cassie Martin is a deputy managing editor. She has a bachelor's degree in molecular genetics from Michigan State University and a master's degree in science journalism from Boston University.

More Stories from Science News on Animals