A new genus and species of pseudosuchian archosaur has been identified from the fossil remains found in southern Brazil.
Tainrakuasuchus bellator. Image credit: Caio Fantini.
Tainrakuasuchus bellator lived in what is now Brazil during the Triassic period, some 240 million years ago.
This ancient predator measured approximately 2.4 m (8 feet) long and weighed 60 kg.
The species had a back covered by bony plates known as osteoderms, structures that are also present in modern crocodiles.
It used its long neck and agile mobility to prey on victims using quick and precise movements, before gripping its prey using its slender jaw profile full of sharp, recurved teeth to hold the target, preventing them from escaping.
“This animal was an active predator, but despite its relatively large size, it was far from the largest hunter of its time with the same ecosystem home to giants as big as 7 m (23 feet) long,” said Dr. Rodrigo Temp Müller, a paleontologists at the Universidade Federal de Santa Maria.
Tainrakuasuchus bellator was a member of Pseudosuchia — precursors of modern crocodiles and alligators.
“Pseudosuchia were a diverse group of animals capable of tackling robust prey, as well as small hunters specialized in catching swift animals,” Dr. Temp Müller said.
“Although its appearance superficially resembles that of a dinosaur, Tainrakuasuchus bellator does not belong to that group.”
“One of the clearest ways for us to distinguish it from dinosaurs lies in the structure of the pelvis where the characteristics of its hip and femur joints are very different.”
“Tainrakuasuchus bellator’s discovery represents the complexity of the ecosystem at the time, with different pseudosuchia species — varying in sizes and hunting strategies — occupying specific ecological niches.”
“Its discovery helps illuminate a key moment in the history of life, the period that preceded the rise of the dinosaurs.”
A partial skeleton of Tainrakuasuchus bellator, preserving parts of the lower jaw, vertebral column, and pelvic girdle, was found in May 2025 in the municipality of Dona Francisca in southern Brazil.
Although the animal’s limbs were not preserved, the expert team believe, alike its close relatives, it moved on all four limbs.
“Tainrakuasuchus bellator’s discovery is further evidence of the ancient connection between Brazil and Africa during the Triassic period — when the world’s continents were united into a single supercontinent, Pangea,” Dr. Temp Müller said.
“Despite the diversity of pseudosuchians, they remain poorly understood, as fossils of some their lineages are extremely rare in the fossil record.”
“The fossils we found underwent a meticulous preparation process in the laboratory, during which the surrounding rock was carefully removed.”
“Once the anatomical details were revealed, we were delighted and really excited to reveal that the specimen represented a species previously unknown to science.”
“What we uncovered was a species that belongs to a predator closely related to one — Mandasuchus tanyauchen — found in Tanzania.”
“This connection between animals from South America and Africa can be understood in light of the Triassic period’s paleogeography.”
“At that time, the continents were still united, which allowed the free dispersal of organisms across regions that are now separated by oceans.”
“As a result, the faunas of Brazil and Africa shared several common elements, reflecting an intertwined evolutionary and ecological history.”
“Tainrakuasuchus bellator would have lived in a region bordering a vast, arid desert — the same setting as where the first dinosaurs emerged.”
“It shows that, in what is now southern Brazil, reptiles had already formed diverse communities adapted to various survival strategies.”
“Moreover, this discovery reveals that such diversity was not an isolated phenomenon.”
The discovery is reported in a paper in the Journal of Systematic Palaeontology.
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Rodrigo Temp Müller et al. Osteology, taxonomy and phylogenetic affinities of a new pseudosuchian archosaur from the Middle Triassic of southern Brazil. Journal of Systematic Palaeontology, published online November 12, 2025; doi: 10.1080/14772019.2025.2573750
