A small predatory reptile lived among the largest apex predators.
Paleontologists have discovered a new species of ancient crocodile-like reptile that once roamed the lands and waters of Brazil.
Fossils found at a fossil site called “Linha Várzea 2” in southern Brazil have now been named Parvosuchus aurelioi, a new ancient species of small predatory reptile that dates back to about 237 million years ago, according to a paper published in Scientific Reports. on Thursday.
The new species belongs to a group of crocodile-like reptiles called pseudosuchians and is the first “unambiguous” gracilissuchid, an extinct genus of tiny pseudosuchians, said Rodrigo Müller, a paleontologist at the Universidade Federal de Santa Maria and lead author of the paper. ABC News via email.
Before dinosaurs ruled the earth, pseudosuchians were a common form of reptile during the Triassic period.
The fossils were discovered in fossil beds that predated those where the earliest dinosaurs were found, giving scientists clues about “ecosystems that existed before the dawn of the dinosaur era,” Müller said.
“The presence of this small predator among the fossils of much larger predators suggests that these ecosystems where Brazil is located today were more complex than we previously imagined,” he said.
Gracilisuchids are extremely rare, Müller said, adding that there are only three other species in the world: two from China and one from Argentina.
According to the paper, smaller pseudosuchians lived alongside larger apex predators.
Parvosuchus aurelioi fossils consist of a partial skeleton, including a complete skull that includes the lower jaw, 11 dorsal vertebrae, a pelvis, and a partially preserved limb.
The remains were covered by a thick layer of rock, at first glance only some parts of the vertebrae were visible, Müller said. After using acid solutions and pneumatic hammers during the preparation process, parts of the skull emerged from the rock, revealing a complete skull, he added.
“The moment I realized the skull was embedded in the rock was overwhelming,” Müller said. “As I slowly removed the layer of rock, part of the orbital rim was exposed. It was as if the animal was looking at me, as if it had been waiting all these interminable years to tell its story.”
The skull measures less than 6 inches in length and has long, slender jaws with pointed teeth that curve back, as well as several openings in the skull.
Müller estimates that the animal was about 6.5 feet long and had a long tail. It probably stood on four legs, which were adapted for walking on the ground, and had blade-like teeth that could tear flesh.
The fossil also had a lightly built skeleton, suggesting the animal was an agile hunter, Müller said.
After carefully examining “every anatomical detail” of the fossil, the researchers noticed features not seen in other similar animals, Müller said.
“At this point it was clear that I had a completely unknown species on my hands,” he said.
There are no clear data on what led to the extinction of gracilissuchids, but a likely hypothesis would be competition with the first dinosaurs or climate changes that occurred during the Late Triassic, when the Earth warmed due to massive volcanic eruptions that released large amounts of carbon dioxide into atmosphere.
Its name comes from the Latin words “parvus” for “small” and “suchus” for “crocodile,” and it was also named in honor of paleontologist Pedro Lucas Porcel Aurélio, who discovered the fossil material.