DISCOVERY! Prehistoric water-dwelling weirdo with sideways teeth and a twisted jaw

Scientists have described Tanyka amnicola, a newly identified species of prehistoric creature that lived 275 million years ago and had a bizarre twisted jaw with sideways-facing teeth.

(image: An artist's illustration showing what the newly described species, Tanyka amnicola, may have looked like. (Image credit: Vitor Silva)

Prehistoric water-dwelling weirdo with sideways teeth and a twisted jaw was already a 'living fossil' 275 million years ago

Live Science News, By Aristos Georgiou, March 4, 2026

Paleontologists have revealed a bizarre prehistoric creature with a twisted jaw and sideways-facing teeth, and the water-dwelling weirdo was already a "living fossil" when it existed 275 million years ago.

The newly described species, named Tanyka amnicola, is an archaic member of the tetrapods — a large group of four-limbed vertebrates that today includes reptiles, birds, mammals and amphibians, according to a study published Wednesday (March 4) in the journal Proceedings of the Royal Society B.

Despite predating the dinosaurs, T. amnicola was already an evolutionary relic in its time, during the Permian period. Many of the earliest tetrapod lineages, known as stem tetrapods, had already disappeared by that time. But the lineage that T. amnicola belonged to seems to have persisted, while tetrapods as a group were diversifying.

"Tanyka is from an ancient lineage that we didn't know survived to this time, and it's also just a really strange animal," lead study author Jason Pardo, a research associate at the Field Museum in Chicago, said in a statement. "In the sense that Tanyka was a remaining member of the stem tetrapod lineage, even after newer, more modern tetrapods evolved, Tanyka is a little like a platypus. It was a living fossil in its time."

Researchers identified the new species from nine fossilized lower jawbones, each roughly 6 inches (15 centimeters) long, recovered from a dry riverbed in northeastern Brazil. Although the creature's lower jawbones were distinctive enough for the team to determine the fossils represented a new species, the lack of other fossilized remains means much about the animal remains unknown.

So it's not a deformation, it's just the way the animal was made.

Jason Pardo, Field Museum research associate Given what is known about its close relatives, however, T. amnicola might have resembled a salamander with a slightly longer snout. It possibly measured up to around 3 feet (around 91 centimeters) in length, Pardo said. The type of rocks in which the fossils were found also indicate that the creature lived in lake environments and presumably had "aquatic habits," according to the paper.

Analysis of the lower jawbones revealed some intriguing features — principally, that they were twisted so that the creature's teeth pointed outward to the sides, rather than upward as seen in virtually all other tetrapods.

When T. amnicola lived, Brazil was part of the supercontinent Gondwana.