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There’s a new tyrannosaur on the block, and it seems it was quite sensitive.

This predecessor of T. rex, Daspletosaurus horneri, or “Horner’s frightful lizard”, is named after Jack Horner, the paleontologist famous for his work advising the makers of the Jurassic Park films.

Markings left on the fossils of this new species suggest it had a snout covered with scales that could sense pressure and temperature.

“Virtually every bone in any skeleton is shaped by surrounding soft tissues,” says of Carthage College in Wisconson, who led the study. “Soft tissues leave their fingerprints on bones.”

The team found that areas on the lower jaw of the tyrannosaur skulls had a bumpy texture that implies they were once covered by armor-like skin similar to a rhino’s. “They’re in patches where the animal would be thrusting its head into a carcass. It looks like it might be protective,” he says. D.horneri has a groove in its jaw for rictal blood vessels, the kind that supply birds’ beaks. Although there’s no evidence the tyrannosaurs had beaks, it could be the early vascular setup for their later evolution, Carr says.

They also found that the tyrannosaurs had small ornamental horns in front of their eyes. The skull is also punctuated by lots of small nerve openings, implying that the species had a mask of flat, sensitive scales much like those on a crocodile’s snout.

Crocodiles use their snouts for feeling out vibrations that help them capture prey and seek out mates. Carr says a tyrannosaur would have had the same ability, its snout acting like one giant, sensitive fingertip.

“It conjures up a horrific scene – a bus-sized tyrannosaur with a face covered in ugly scales, sniffing you out with its nose and then sensing your movements with its skin receptors on its snout,” , a paleontologist at the University of Edinburgh, UK.

At 9 metres long and 2 metres tall, this new species was a little smaller and more primitive than T. rex, but it would have been king of the food chain in western North America.

“It was the top gun about 10 million years before T. rex came onto the scene,” Brusatte says. “It would have been a ferocious animal and one of the largest predatory dinosaurs not named T. rex.”

Mighty morphing tyrannosaurs

D. horneri lived in what is now Montana and evolved directly from D. torosus, another tyrannosaur that roamed across Alberta, Canada, during the Cretaceous period.

It’s rare that dinosaurs morph directly from one species into the next, instead of branching off into similar species that live during the same period.

The Two Medicine formation in northern Montana where these tyrannosaurs originated has been mined extensively for fossils, and paleontologists have a lot of specimens to base their deductions on, but the fossil record isn’t perfect.

“One discovery of a specimen in a different time period would just throw the whole direct descendant argument out the window. There’s always the chance that it’s just the fossil record not being complete, which is often a problem for palaeontologists,” says at the University of Cambridge.

Just as the Rocky mountains were starting to form 74.4 million years ago, the last of Horner’s frightful lizards died out.

“Tyrannosaurus rex replaced all the earlier tyrannosaurs in North America. So as far as we know, horneri was the last of its kind,” Carr says.

Read more: T. rex didn’t need proper arms thanks to its neck