A recently discovered crocodile ancestor, named Carolinensis Carnufex , was the top predator in North America before dinosaurs reached the continent.
Carnufex carolinensis was nearly ten feet tall, lived on the ground , walked on hind legs, and hunted for food prey armored reptiles and primitive mammalian relatives of then-existing ecosystems in what is now North Carolina.
The discovery is due to paleontologists from North Carolina State University and the Museum of Natural Sciences of that North American state, who recovered fragments of the Carnufex skull, the vertebral column and the upper forelimb of the Peking Formation in the county of Chatham. Given that the skull was in pieces, it was not easy to imagine what it would have looked like in its entirety .
To obtain a reconstruction, the experts scanned each of the bones with the latest imaging technologies and created a three-dimensional model of the reconstructed skull , drawing on more complete ones from close relatives that included the missing pieces.
The Peking Formation contains sediments dating back 231 million years from the beginning of the Late Triassic –Carnico–, when present-day North Carolina was a warm, humid equatorial region that was beginning to separate from Pangea.
According to Lindsay Zanno, a research professor at the University of that state, director of the Laboratory of Paleontology and Geology and main author of the find, the fossils of this period are key, since they show the oldest appearance of crocodilomorphs and theropod dinosaurs , two groups which developed in the Triassic and have survived to this day in the form of crocodiles and birds: “The discovery of Carnufex , one of the first and largest crocodilomorphs, brings new data to the debate about the main land predators in Pangea.”
Among the typical predators of Pangea were the huge rauisuchids and the ferocious Poposauroidea , cousins of ancient crocodiles that became extinct in the Triassic. In the southern hemisphere, “these animals hunted alongside early theropod dinosaurs, and there was a large concentration of one of predators,” says Zanno. The Carnufex finding indicates that in the north, large-bodied crocodilomorphs, not dinosaurs, were adding to the main predator niches, increasing their diversity .
So the earliest ancestors of crocodiles were among those competing for the best hunting grounds before the reign of the dinosaurs in North America. As the Triassic drew to a close, extinction decimated many of these predators and only small-bodied crocodilomorphs and theropods survived.
Image: Jorge Gonzales
