Kank australis: New “Heron-Like” Unenlagiid from Late Cretaceous Patagonia Stalked Freshwater Wetlands

In a May 2026 Journal of Vertebrate Paleontology paper, Argentine and Japanese researchers have named Kank australis, the first unenlagiid theropod from the Maastrichtian Chorrillo Formation of southwestern Patagonia, Argentina. Discovered at La Anita ranch near El Calafate, Santa Cruz Province, the fossils—cervical vertebrae, pedal phalanges, and shed teeth—date to approximately 70 million years ago and reveal a slender, 3-metre-long predator adapted to wetland environments.

The dinosaur’s long snout, tiny recurved teeth, and bird-like wing bones suggest a heron- or egret-style hunting strategy: wading through shallow freshwater marshes and snatching fish or small vertebrates. Its highly pneumatized cervical vertebra and troodontid-like pedal phalanx set it apart from northern Patagonian unenlagiids, confirming it as a distinct species.

Lead author Matías J. Motta noted: “Kank helps bridge a distributional gap for the Late Cretaceous of southern Patagonia, connecting known records from northern Patagonia and Antarctica.” The Chorrillo Formation preserves a temperate, humid wetland ecosystem teeming with fish, snails, lizards, and even a platypus-like mammal—perfect habitat for this specialized stalker.

The discovery underscores that unenlagiids were morphologically disparate and ecologically flexible, thriving in southern Gondwanan wetlands right up to the end of the Cretaceous. After decades of sparse southern records, Kank australis proves Patagonia hosted diverse, fish-hunting “raptors” alongside its famous тιтanosaur herds.