A new species of dinosaur has been uncovered in the US state of Utah.

The akainacephalus johnsoni is around 76 million-years-old and had heavily-armored bones.

A fossil was originally found back in 2008 by paleontologist Scott Richardson in the Kaiparowits Formation of Grand Staircase-Escalante National Monument.

A crew from the Natural History Museum of Utah (NHMU) began excavations soon after.

NHMU's chief curator Randall Irmis said the site was "really unusual" in that "it had bones from a number of different types of animals.

"And not only individual bones, but associated skeletons."

Skull of the the akainacephalus johnsoni | Image via @NHMU on Twitter

There was a skeleton of a duckbilled dinosaur Gryposaurus monumentensis, a new species of pig-nosed turtle called Arvinachelys goldeni, and a as-yet unnamed new species of prehistoric caiman relative, for starters.

They also found the bones of a heavily-armored, herbivorous dinosaur never discovered before.

Mr Irmis added: "We have a large portion of the skeleton, including nearly all of the skull, a lot of the vertebral column, the pelvis, as well as the limbs and ribs, and a lot of the armor, as well.

"It's pretty rare to find so much of the skeleton in one place."

In technical terms, Akainacephalus is a ankylosaurid - this is the specific subset of armored dinosaurs that included species with formidable tail clubs.

A scientific illustration of the akainacephalus johnsoni by Andrey Atuchin | Image: Natural History Museum of Utah

The old bones also connect two continents.

At 76 million-years-old, Akainacephalus is one of the oldest ankylosaurids yet found in North America.

And along with another dinosaur recently found in New Mexico, Irmis said, Akainacephalus is more closely related to ankylosaurids found in Asia than other species from North America.

This is a hint that ankylosaurids crossed an ancient land bridge from Asia to North America - one of several interchanges where they wandered from ancient Mongolia and China to western North America.

Randy Johnson from the Natural History Museum of Utah - for whom the dinosaur was named - standing next to the new species of ankylosaurid dinosaur | Image via @NHMU on Twitter

But the most striking aspect of Akainacephalus was its armor.

Its head was particularly spiky, and from its snout to the end of its mace-like tail, it was covered in osteoderms - bony deposits forming scales - that offered protection.