Tanyka amnicola survived on the southern supercontinent of Gondwana throughout the Early Permian date, around 275 million years back.

Tanyka amnicola is from an ancient family tree that we didn’t understand made it through to this time, and it’s likewise simply a truly unusual animal,”stated Dr. Jason Pardo, a paleontologist at the Field Museum.

” The jaw has this strange twist that drove us insane attempting to figure it out.”

“We were scratching our heads over this for several years, questioning if it was some sort of contortion.”

“But at this moment, we’ve got 9 jaws from this animal, and they all have this twist, consisting of the truly, truly unspoiled ones. It’s not a contortion, it’s simply the method the animal was made.”

Tanyka amnicola was a stem tetrapod, the earliest tetrapod family tree that ultimately divided into 2 groups– ones that laid eggs beyond water, and ones that laid their eggs in the water.

Today’s reptiles, birds, and mammals are all descendants of the branch that laid leak-proof eggs on land; modern-day amphibians like frogs and salamanders are the loved ones of the tetrapods whose eggs required to stay damp.

Even after the tetrapod household split into these brand-new groups, some of the stem tetrapods stayed. Tanyka amnicola was among them.

“In the sense that Tanyka amnicola was a staying member of the stem tetrapod family tree, even after more recent, more modern-day tetrapods progressed, Tanyka amnicola is a little like a platypus. It was a living fossil in its time,” Dr. Pardo stated.

There’s a lot about Tanyka amnicola that stays a secret: particularly, its body.

“We discovered these jaws in seclusion, and they’re truly strange, and they’re extremely unique,” stated Dr. Ken Angielczyk, a manager of paleomammalogy at the Field Museum.

“But up until we discover among those jaws connected to a skull or other bones that are definitively related to the jaw, we can’t state for sure that the other bones we discover near it come from Tanyka amnicola“

Tanyka amnicola‘s jawbone alone sufficed to reveal the scientists what an uncommon animal it was.

“Run your tongue over the teeth on your lower jaw. Feel how the tops of your teeth are dealing with up, towards the roofing of your mouth?” they stated.

“In Tanyka amnicolathe lower jaw was twisted, so that rather of dealing with up, the teeth explained to the sides.”

“Meanwhile, the part of its jawbone that, in us, deals with the tongue, in Tanyka amnicola is dealing with up towards the roofing system of its mouth.”

“This surface area of Tanyka amnicola‘s jawbone is covered in a series of smaller sized teeth called denticles, which form a grinding surface area sort of like a cheese grater.”

The researchers have yet to discover the bones that would comprise Tanyka amnicola‘s upper jaw, however they envision its leading teeth and denticles were oriented likewise to the ones on the lower jaw.

“We anticipate the denticles on the lower jaw were rubbing up versus comparable teeth on the upper side of the mouth,” Dr. Pardo stated.

“The teeth would have been wearing versus each other, in a manner that’s going to produce a reasonably special method of feeding.”

In basic, teeth that have the ability to grind versus each other are utilized for squashing up plant product.

“Based on its teeth, we believe that Tanyka amnicola was a herbivore, which it consumed plants a minimum of a few of the time,” stated Dr. Juan Carlos Cisneros, a scientist at the Federal University of Piauí.

“It’s unexpected that a stem tetrapod like Tanyka amnicola would have developed to consume plants, considering that the majority of its fellow stem tetrapods just consumed meat.”

The findings appear in the journal Procedures of the Royal Society B

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Jason D. Pardo et al2026. An aberrant stem tetrapod from the Early Permian of Brazil. Proc Biol Sci 293 (2066 ): 20252106; doi: 10.1098/ rspb.2025.2106