They called it Hellboy, and not just for the two horns sticking out over its eyes.
The skull from the new species of dinosaur did have cranial similarities to the famous comic book and movie character. But it was where it was found that really earned it the nickname.
"The Hellboy nickname is because of all the problems with the excavation," said Caleb Brown of the Royal Tyrrell Museum of Paleontology, whose paper on the new dinosaur and its bizarre armour-plating was published Thursday.
The 1.6-metre skull was found only about a metre above the water along southern Alberta's Oldman River, a waterline that fluctuates widely over the seasons. It was on a steep cliff, prone to dangerous rockfalls.
The rock that housed the dinosaur was very hard. To top it off, that section of the river is crucial habitat for Alberta's provincial fish, the bull trout. No sediment or debris was allowed to fall in the water.
Digging out the 68-million-year-old fossil took years.
"It was a hellish quarry to work in," Brown laughs.
But it was worth it. Not only is Hellboy — or Regaliceratops peterhewsi, to be formal — a completely new species. It is spectacular. Part of a family that includes the iconic Triceratops, Hellboy has the longest nose horn of any of those three-horned monsters — up to 28 centimetres long.
And while Brown calls the horns over Hellboy's eyes "almost comically short," the dinosaur did sport a massive, bony shield protecting its neck and shoulders. That shield featured a row of large, triangular bony plates along its edge, giving it the appearance of a crown.
"This is a pretty bizarre-looking one."
It's one more variation in a family of dinosaurs that sports a panoply of variation in horns and shields, or frills. The number of known horned-dinosaur species has tripled over the last 15 years or so, and that variety is what finally gave scientists a clue as to their purpose.
"When the first horned dinosaurs were found — this was Triceratops — we thought these were probably used for defence," Brown said. "You have these iconic images of Triceratops doing battle with Tyrannosaurus rex.
"(But) the more horned dinosaurs that we find, the less the explanation of defence makes sense. There are a number of species where their horns would be pretty much useless in defence.
"What we're thinking now is that these were used for display. These were to impress members of the same or opposite sex and communicate with other species. That plate at the back of his skull is pretty much a billboard advertising for that individual."
Brown says Hellboy also shows how evolution can sometimes come up with similar answers to similar situations.
Horned dinosaurs come in two families: chasmosaurs and centrosaurs.
Chasmosaurs, such as Triceratops, had small nose horns, big eye horns and scallops frills. Centrosaurs, which became extinct shortly before Hellboy appeared on the scene, had big nose horns and small eye horns.
Although Hellboy was a chasmosaur, he looked like a centrosaur. Brown said that's an example of how one species can move into an empty niche, sometimes by adopting some of the features of the previous tenant.
And Brown is convinced that there are more like Hellboy out there.
"If there's this thing out there, there must be other things that are related to this thing as well. We still have a lot to learn."
