In a dry riverbed deep within Brazil’s Amazon forest, paleontologists unearthed nine remarkably preserved jawbones from a bizarre ancient reptile named Tanyka amnicola, a species that lived 275 million years ago during the early Permian Period. Named from the Indigenous Guaraní word for “jaw” and Latin for “living by the river,” Tanyka belonged to an ancient stem tetrapod lineage that persisted as a “living fossil” alongside more modern relatives, much like the platypus among mammals. The discovery, detailed in Proceedings of the Royal Society B, fills critical gaps in our understanding of Gondwanan ecosystems during a time when fossils from the Global South remain scarce.

What sets Tanyka apart is its jaw’s unprecedented twisted structure, where the lower teeth angled outward and sideways while inner denticles formed a rough grinding surface oriented upward like a cheese grater. This configuration suggests Tanyka was one of the earliest known herbivores among stem tetrapods, rasping plant material between upper and lower jaws in a feeding style unlike anything alive today. Researchers estimate the animal reached up to three feet long with a salamander-like body and longer snout, thriving in freshwater lakes.

The fossils from Brazil’s Pedra de Fogo Formation reveal how ancient communities functioned, with Tanyka likely playing a unique herbivorous role in a world dominated by carnivorous relatives. Lead author Jason Pardo noted the team’s years-long puzzle over the jaw’s twist, confirmed across all nine specimens as a genuine anatomical feature rather than deformation.

BREAKING: Paleontologists Discover 275-Million-Year-Old “Living Fossil” Reptile With a Twisted Jaw That Ground Plants Like a Cheese Grater, An Ancient Holdover That Survived Long After Its Relatives Went Extinct 🦎