Researchers have identified a new fossil reptile from southern Brazil that lived about 240 million years ago, long before dinosaurs and modern crocodiles appeared. The species, named Silescelida acristata, was found in Dona Francisca in Rio Grande do Sul state, in rocks that are part of the UNESCO Quarta Colônia Geopark, according to ScienceDaily.
The study was carried out by scientists from the Quarta Colônia Center for Paleontological Research at the Federal University of Santa Maria, along with researchers from UFRGS and PUCRS. Their findings were published in the journal Scientific Reports.
According to the report, the fossil helps fill an important gap in the history of archosauriforms, the reptile group that eventually gave rise to archosaurs, including the lineages that led to crocodiles, dinosaurs and birds. The animal lived during the Middle Triassic, when ecosystems were still recovering from the Permian-Triassic extinction event.
Silescelida acristata was a small, slender, four-legged reptile that was likely a predator of smaller animals. Its preserved limb bones, especially the femur, suggest it had a more semi-erect posture that may have improved how it moved across the ground.
Researchers also say the fossil may be related to the Euparkeriidae, a rare and still poorly understood group of archosauriforms. That would extend the known range of these animals, since fossils linked to the group had previously been found mainly in Africa, Asia and Europe. Part of the specimen was missing for more than 20 years before being found again in 2022, allowing scientists to confirm its origin and formally describe it as a new species.
