Paleontologists uncovered a fragment of jawbone in a dry riverbed in Brazil that led to the identification of a new vertebrate species named Tanyka amnicola.
The fossil, dated to 275 million years ago, belongs to a lineage previously thought to have gone extinct earlier but persisted longer in the Amazon region, according to research published in Proceedings of the Royal Society B. The team, comprising scientists from Brazil, the UK and Canada, recovered eight fossil fragments from the same animal, none of which form a complete skeleton but collectively indicate a new tetrapod species.
The internal denticles on the jaw suggest Tanyka could process hard foods, while the unusual twisting of the jaw bones, with some teeth pointing outward and smaller teeth lining the inside, indicates it may have been among the earliest vertebrates to chew plants for sustenance.
Tanyka represents a surviving lineage from an early stage of tetrapod evolution
Most of Tanyka’s relatives died out 275 million years ago, but this Amazonian population endured longer and later contributed to the evolution of amphibians, reptiles and birds. Dr Jason Pardo, lead author of the study, said Tanyka resembled a platypus in belonging to a basal tetrapod lineage that survived after more modern tetrapods evolved, calling it a “living fossil” in its time.
The name Tanyka amnicola comes from the Guaraní language and means “jaw that lives by the river.” Dr Martha Richter of the Natural History Museum in London noted that the team initially suspected the fossils belonged to a fish, only recognizing their true nature after laboratory preparation.
Discovery highlights the paleontological potential of underexplored Amazon regions
The Amazon spans 5 to 7 million square kilometres, with many areas still unexplored, allowing for annual scientific campaigns to uncover new findings. This find follows a pattern where isolated populations in remote regions preserve ancient traits longer than elsewhere, similar to the 2022 discovery of a coelacanth population in Indonesian waters that had been thought extinct for 66 million years.
What does the name Tanyka amnicola mean?
It means “jaw that lives by the river” in the Guaraní language.
How old is the Tanyka fossil?
It dates back to 275 million years ago.