In a limestone-lined landscape of meandering rivers and seasonal ponds, a small dinosaur no larger than a tall human hunted fish with the precision of a modern heron, its long flexible neck twisting and striking at prey in waters that flowed through southern Patagonia 70 million years ago. Paleontologists have now given this ancient fisher its name: Kank australis, a newly discovered species that challenges everything we thought we knew about raptors.
The fossil remains—including teeth with sharp ridges, neck vertebrae with internal air chambers, and distinctive toe bones—were unearthed at La Anita farm near El Calafate in Santa Cruz, Argentina. Dr. Matías Motta and his colleagues at the Bernardino Rivadavia Natural Sciences Museum in Buenos Aires identified the species in work published today in the Journal of Vertebrate Paleontology. The first fragments surfaced in 2018, but it wasn't until the discovery of a critical neck vertebra in 2024 that researchers recognized what they had found.
Kank australis belonged to the unenlagiids, a family of small-to-medium theropod dinosaurs found across Late Cretaceous South America, Antarctica, Australia, and Madagascar. Adults likely grew to about 2.5 to 3 meters long—considerably smaller and more gracile than its formidable cousin, Austroraptor cabazai, which stretched to around 5 meters. Like other unenlagiids, Kank carried an enlarged raptorial claw on its second toe, but its teeth reveal its true nature: sharp, pronounced ridges designed for gripping slippery prey.
The anatomy tells a remarkable evolutionary story. The cervical vertebrae of Kank display special structures for muscle attachment and blood vessel protection—features modern herons possess for their complex neck movements and diving strikes. "This suggests Kank may have been an active fisher, contrasting with common portrayal of raptors as agile terrestrial predators, like Velociraptor from the Northern Hemisphere," Dr. Motta explains. The evidence accumulates: elongated snouts, numerous teeth, long flexible necks, and perhaps most compellingly, fossil remains discovered alongside fish.
The world Kank inhabited bore little resemblance to the cold, dry Patagonia of today. Analysis of ancient soils and fossilized plants reveals a temperate, humid climate with seasonal rainfall, studded with aquatic plants like water lilies. This ecosystem sustained an intricate web of life—fish and insects, frogs and lizards, turtles and semi-aquatic mammals including Patagorhynchus pascuali, a monotreme relative of modern echidnas and platypuses. It was not a safe world. Larger carnivores patrolled these rivers, particularly Maip macrothorax, a megaraptorid dinosaur stretching over 10 meters in length, capable of preying upon a creature like Kank.
The discovery of Kank australis fills a critical gap in our understanding of unenlagiid distribution. While seven species have been documented in northern Patagonia, southern Patagonia had yielded only scattered, unidentifiable remains. Now, for the first time, the evolutionary record connects known populations from north to south and reaches to Antarctica, revealing that this family thrived across different latitudes of South America during the Late Cretaceous. It is a reminder that raptors were far more diverse in their hunting strategies than Hollywood suggested—some swift and terrestrial, others patient and aquatic, all exquisitely adapted to their worlds.