Fossil of a new species of dinosaur with bizarre horns discovered in America
The fossilized remains of a new dinosaur have just been discovered in the mountains of Montana.
Lokiceratops rangiformis is one of the largest ceratopsian dinosaurs to ever roam our planet, belonging to a family of horned beasts that includes Triceratops and Styracosaurus.
Furthermore, the two long, curved horns that adorned the crest of the skull are the most striking ever documented. It is from these horns that the dinosaur takes its name, from the spectacular helmet worn by the Marvel character Loki.
Lokiceratops lived 78 million years ago, along with many other collared dinosaurs of the Centrosaurine subfamily on what was once the Cretaceous island continent of Laramidia, but was larger and heavier than all of them. Although the bones all come from a single individual, by a huge stroke of luck they make up the majority of the dinosaur's skull. From this we know that Lokiceratops had horns unlike any other, crowned by two large asymmetrical caribou-like horns on top of the frill: the large shield-shaped bony plate found in ceratopsians. It also lacked the nasal horn typical of other animals of its species.
“This new dinosaur pushes the limits of the bizarre ceratopsian headdress, sporting the largest frilled horns ever seen on a ceratopsian,”
says paleontologist Joseph Sertich of the Smithsonian Tropical Research Institute.
Paleontologists believe that dinosaurs used their horns just as birds use their different feathers, for mate selection or species recognition.
“These skull ornaments are one of the keys to unlocking the diversity of horned dinosaurs and demonstrate that evolutionary selection for flashy displays contributed to the dizzying richness of Cretaceous ecosystems.”
The fossilized bones were found in the Judith River Formation in Montana, a fossil deposit from which the bones of four other dinosaurs were recovered. But when Sertich and his colleague, paleontologist Mark Loewen of the University of Utah, began reconstructing the skull from excavated bones in 2019, they realized they were looking at something no one had ever seen before.
Lokiceratops is estimated to have measured around 6.7 meters in length, with a skull more than 2 meters long from the nose to the tips of the horns. And it would have tipped the scales at about 5 tons. This puts it on par with the largest elephants found on Earth today.
It's still not as big as Triceratops, which arrived about 10 million years later in Earth's history, but you'd still want to get out of the way if it charged at you head-on. Another interesting thing about Lokiceratops is the other dinosaurs in the formation where its remains were found. Three of the other species are also Centrosaurines, closely related to each other and Lokiceratops, and the fourth was another horned dinosaur.
The other Centrosaurines are also not known outside Laramidia.
“Previously, paleontologists thought that up to two species of horned dinosaurs could coexist in the same place at the same time,”
explains Loewen.
“Incredibly, we identified five of them living together at the same time.”
The isolation of ceratopsian dinosaurs on Laramidia is likely what led to the large size and diversification of animals found there, including the distinctive arrangement of horned protuberances on their giant heads. This rapid speciation can be found in isolated animal communities, particularly in Galapagos finches. This suggests we may be vastly underestimating the diversity of dinosaurs, the researchers say.
“Rapid evolution may have led to a 100- to 200-thousand-year turnover of individual species of these horned dinosaurs,”
says Loewen, adding,
“Lokiceratops helps us understand that we are only scratching the surface when it comes to diversity and relationships inside the horned dinosaur family tree.”
