A new dinosaur species that stalked fish along ancient rivers in southern Patagonia has been identified from fossil remains including teeth, vertebrae, and toe bones, according to a report by Phys.org.
The species, named Kank australis, lived approximately 70 million years ago and belongs to a family of small-to-medium dinosaurs called unenlagiids, relatives of Velociraptor. Based on comparisons with a related species, researchers believe adults likely grew between 2.5 and 3 meters long.
The discovery was described by paleontologist Dr. Matías Motta of the Bernardino Rivadavia Natural Sciences Museum in Buenos Aires and colleagues in a paper published in the Journal of Vertebrate Paleontology.
The environment K. australis lived in was dramatically different from the cold, dry Patagonia of today. "Kank lived in a landscape of meandering rivers and streams with seasonal ponds, inhabited by aquatic plants such as water lilies and animals including fish, insects, and various mollusks," said Dr. Motta. Analysis of ancient soil samples and fossilized plant material indicates that 70 million years ago the region had a temperate, humid climate with seasonal rainfall.
The anatomy of the dinosaur's neck bones points toward a hunting style more like a modern heron than a terrestrial predator. "The cervical vertebrae of Kank show special structures for muscle attachment and the protection of neck blood vessels — features particularly important in modern birds with complex neck movements, such as herons," said Dr. Motta. "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."
The find also fills a gap in the known distribution of unenlagiids across South America. Seven species had previously been recorded in northern Patagonia, but the fossil record from the south of the region had yielded only scattered, unidentifiable remains. "Kank helps bridge a distributional gap for the Late Cretaceous of southern Patagonia, connecting known records from northern Patagonia and Antarctica, and showing that this family was dispersed across different latitudes of South America," Dr. Motta said.
The fossils were excavated at La Anita farm near the city of El Calafate in Santa Cruz province. Field excavations at the site have been ongoing since 2018, producing a range of material from the Late Cretaceous period.
The unenlagiid family has been found across a wide geographic range, with specimens recovered from South America, Antarctica, Australia, and Madagascar. K. australis adds to that picture by confirming the group's presence deep into southern Patagonia during the Late Cretaceous, a time and place that had remained largely blank in the fossil record until now.
