New pre-dinosaur era crocodile-like species discovered
Paleontologists have unearthed a new species of ancient reptile, Parvosuchus aurelioi, from the Triassic Period approximately 237 million years ago. The fossils were found in a fossil-rich area known as "Linha Varzea 2" in southern Brazil's Santa Maria Formation. The discovery was detailed in a paper published in Scientific Reports on June 20. This new species is part of the pseudosuchians group, resembling crocodiles, and is described as the first "unequivocal" gracilisuchid, an extinct genus of small pseudosuchians.
Parvosuchus aurelioi: A rare addition to Gracilisuchidae
Rodrigo Muller, a paleontologist at the Federal University of Santa Maria in Rio Grande, stated that the Gracilisuchidae are rare in the fossil registry, with only three species previously known: two in China and one in Argentina. The discovery of Parvosuchus aurelioi brings the total number of known species to four, marking it as Brazil's first uncontested Gracilisuchidae. Interestingly, these creatures were already extinct when dinosaurs appeared later in Earth's evolutionary history.
Unveiling the fossil of Parvosuchus aurelioi
The fossil remains of Parvosuchus aurelioi were initially concealed by a thick layer of rock, with only a few vertebrae visible. Acid solutions and pneumatic hammers were used to reveal portions of the cranium from the rock, leading to the discovery of a complete skull. Muller described the creature as approximately 6.5 feet long with a long tail and four legs designed for walking on land, equipped with blade-like fangs for tearing through flesh.
Parvosuchus aurelioi: A glimpse into pre-dinosaur evolution
The fossils of Parvosuchus aurelioi include a complete skull, 11 vertebrae, the pelvis, and some limb bones. This terrestrial predator represents one of the earliest branches of a lineage known as Pseudosuchia that later included the crocodile branch. Parvosuchus lived during a time of evolutionary innovation following Earth's worst mass extinction 252 million years ago. The last undisputed members of the Gracilisuchidae died out about seven million years before the first dinosaurs appeared.
About the Santa Maria Formation
The Santa Maria Formation in southern Brazil consists of Middle to Late Triassic sedimentary rocks famous for their abundant tetrapod fossils. Among these, it features one of the oldest and best-preserved associations of dinosaur and dinosaur precursor species, including new species of Lagerpetidae and Sauropodomorph. Tetrapod species are four-limbed vertebrates that include amphibians, reptiles, birds, and mammals.
