In 2024, a horned dinosaur skull with an extraordinary crown was found in Montana, and it reshaped what scientists knew about prehistoric North America

A skull unearthed in the badlands of northern Montana may have just changed everything we know about how dinosaurs evolved and how much diversity is still hidden away in the American West.

In 2024, paleontologists announced the discovery of a new species of horned dinosaur, Lokiceratops rangiformis, near the Montana-Canada border. This fossil is about 78 million years old, and from the moment researchers got a good look at it, they knew they were looking at something really weird. A peer-reviewed study published in PeerJ by Loewen et al. described the skull as lacking a nasal horn, having two oversized blade-like frill horns (the largest frill horns recorded on any dinosaur), and an asymmetrical mid-frill spike. This last was not regarded as damage or a quirk of preservation. It was regarded as a characteristic of the species.

A crown we’ve never seen before
Lokiceratops is named after the Norse trickster god Loki, and the comparison is well-earned. The animal's headgear is, indeed, a mismatched affair, with frill ornaments that look like nothing so much as uneven caribou antlers as opposed to the balanced, symmetrical frills that most people imagine on ceratopsians like Triceratops. It was over five tonnes and about 22 feet long, no small animal by any standards. But the skull is what makes it memorable.


The frill and horns are important in distinguishing individual species in horned dinosaurs. Slight differences in form and layout may indicate a completely separate lineage. The Lokiceratops skull provided one of the most dramatic examples of that yet discovered anywhere in Montana. Scientists were quick to name it a new genus and species. The asymmetrical frill was no accident. It was the signature.

What this skull tells us about ancient Montana
The discovery is important for more than just the attention-grabbing headwear. Lokiceratops was discovered in the Judith River Formation, a rock unit that has yielded many important fossil finds across Montana. The geographic context is what makes this find especially significant. Scientists identified it as a member of a group of ceratopsid species that once lived in a surprisingly small area near the Montana-Canada border. This one small area seems to have been home to four different species of centrosaurine, a diversity that surprised even seasoned paleontologists.

That density of species speaks to something larger about how life arranged itself on ancient Laramidia, the western landmass that blanketed much of what is now the American West during the Late Cretaceous. Many horned dinosaur species seem to have been very regional, evolving in place and staying there, rather than broad populations across the continent.

The American West was a mosaic, not a plain
This idea did not begin with Lokiceratops. A peer-reviewed study published in PLOS ONE documented distinct co-occurring lineages of ceratopsids in northern and southern Laramidia. It concluded that this pattern represents the first documented case of intracontinental endemism within dinosaurs. In plain English, that means dinosaurs were evolving independently in different parts of the same landmass, like isolated populations on different islands might diverge over time, except these were pockets of a single continent, not islands.

Lokiceratops fits that pattern and strengthens it. The find shows that centrosaurines underwent rapid regional radiations and extreme endemism, meaning that new species appeared quickly in small geographic areas and did not spread widely to remain the same over large distances, according to the study by Loewen et al. That’s a big change from older assumptions about how widespread the dinosaurs were. It also suggests that the Late Cretaceous West was not a single connected dinosaur landscape but instead a patchwork of separate, locally adapted communities.

Why it matters for paleontology in the US
The implications are real and exciting for American paleontology. If horned dinosaurs were this regionally specialized, then the rocks of Montana, Utah and neighboring states probably hold many species yet to be discovered. Each skull recovered from the right formation could represent a lineage that evolved in isolation, took on its own distinctive look, and left its bones in a particular patch of badlands. Lokiceratops is a reminder that the American West continues to give up its secrets, and some of the most dramatic may still be waiting in the ground.

What started as one strange skull from a Montana quarry has turned into a case for rethinking the ecological map of Cretaceous North America, one weird, asymmetrical crown at a time.