WASHINGTON (AP) — It was a fierce and toothy hunter that raced across lush African plains to catch and rip apart its prey 90 million years ago.
“I would not have wanted to be around when it was on the prowl,” said Paul Sereno, a University of Chicago researcher who discovered fossils of the previously unknown dinosaur in Morocco.
Sereno unveiled his discovery on Thursday and said he named the new species Deltadromeus agilis, or “agile delta runner” because the bones show that it was “the most slender and agile large predator that we know of.”
“It would have been a really ferocious, fast-moving hunter,” he said in an interview. “It was about 25 feet long and its stride would have been as much as nine feet on the run. It looks like it could really, really move.”
Sereno, in a study to be published Friday in the journal Science, also announced discovery of the most complete skull ever found for Carcharodon-tosaurus saharicus, an animal that may have been the largest and most fearsome animal in the world 90 million years ago.
With teeth five inches long set into five-foot long jaws, the animal would have been able to gobble a human in a single bite. The skull was lightly built and “narrow as a pancake,” said Sereno, but it was supported by a long and powerful neck.
Carcharodontosaurus saharicus, which means “shark-toothed lizard from the Sahara,” closely resembled Tyrannosaurus rex, the meat-eater that dominated North America 65 million years ago, Sereno said.
“They were examples of independent evolution taking place on separate continents,” he said. “They independently reached about the largest size possible for a dinosaurian carnivore. They are right at the top in size for predators on land.”
They were about 45 feet long, stood perhaps 11 feet at the hip and weighed perhaps seven tons, Sereno said.
But they were no geniuses. The Carcharodon-tosaurus brain was only 1/15 the size of a human brain, he said.
“This animal had striking teeth,” said Sereno. “They are blade-shaped, slightly curved, with a strange group of wrinkles along the edge of the crown. They would have eaten and sliced their food differently than the Tyrannosaurus.”
Fossils for both animals were found in a Moroccan sandstone formation called Kem Kem, on the edge of the Sahara Desert.
Sediments and other fossils near the dinosaur remains put their age at 90 to 92 million years, long before the earliest known T-rex developed in North America, he said.
“Africa was different then,” Sereno said. “It was much wetter. It was a rich environment.”
Sereno said the fossils suggest that there was a rapid and independent evolution of meat-eating species in North America, Africa and South America after the continents drifted apart some 100 million years ago.
David B. Weishampel, a dinosaur paleontologist at Johns Hopkins University in Baltimore, said the find is “rather significant” because it represents “a new group of meat-eating dinosaurs we have not recognized before.”
But he said Sereno’s conclusions about distribution of the species are not strongly supported by the fossils.
“We don’t know from this how abruptly these guys evolved,” said Weishampel.