Paleontologists in Argentina have discovered an unprecedented species of non-enraged dinosaur, canku australis, that lived in freshwater wetlands during the Late Cretaceous period. This discovery reinforces the notion that certain dinosaurs had evolved specialized adaptations for catching fish.
The newly characterized species, canku australis, thrived approximately 70 million years ago during the Late Cretaceous period.
This ancient reptile inhabited environments adorned with meandering rivers, seasonal ponds, and aquatic flora like water lilies, alongside a diverse fauna including fish, insects, and various mollusks.
canku australis grew to an estimated length of about 2.5 to 3 meters (8.2 to 9.8 feet).
This dinosaur was part of the Urticidae family, a group of feathered, bird-like theropods closely related to famous dinosaurs like Velociraptor, known to inhabit regions such as South America, Antarctica, Australia, and Madagascar.
Dr. Matias Motta from the Bernardino Rivadavia Museum of Natural Sciences and his team stated, “The paraavian family Urticidae is documented through fossils from various Cretaceous basins across South America, Madagascar, Australia, and Antarctica, but the Northern Patagonia region, particularly the Neuquén Basin, yields the most notable species.”
“This includes at least eight species, primarily from the Cenomanian-Santonian Formation, with the exception of the Maastrichtian, including Austroraptor kabazai,” he added.
“The evolutionary lineage and biodiversity of the Urticidae in South America remains understudied.”
“The discovery of canku australis helps bridge gaps in the Late Cretaceous fossil record of southern Patagonia and links existing records from northern Patagonia and Antarctica, highlighting the dispersal of this family across varying latitudes in South America.”
Fossil remains of canku australis—which include teeth, vertebrae, and toe bones—were discovered in the Chorrillo Formation at La Anita farm near El Calafate, Santa Cruz, Patagonia, Argentina.
Dr. Motta noted, “Excavations at this site have been ongoing since 2018, revealing a broad range of plant and animal fossils.”
The first remains of canku australis were identified in 2018, although initial findings were too fragmentary to classify it as a new species.
Subsequent expeditions yielded additional materials, culminating in the discovery of cervical vertebrae in 2024, which played a crucial role in recognizing this new Unenragine dinosaur.
These fossils suggest valuable insights into the lifestyle and behaviors of canku australis.
Dr. Motta explains, “The cervical vertebrae of canku australis feature unique structures for muscle attachment and the protection of blood vessels in the neck, a vital characteristic seen in modern birds like herons with complex neck movements.”
This evidence implies that canku australis might have been an adept fisherman, contrasting with the traditional perspective of raptors such as Velociraptor as primarily terrestrial predators.
“Like its relatives, canku australis possessed a prominent raptor claw on its second toe, yet it distinguished itself with teeth characterized by sharp, pronounced longitudinal ridges and notably pneumatic cervical vertebrae containing internal air chambers.”
This species is also smaller and more agile compared to other non-enragid dinosaurs from the Late Cretaceous, such as Austroraptor kabazai.
The findings contribute further evidence supporting the idea that the Urticidae were fish-eaters.
Dr. Motta remarked, “Their elongated snouts, numerous teeth, and long, flexible necks suggest adaptations for fishing, akin to modern herons.” Remarkably, fossils of canku australis were found alongside fish remains, reinforcing this hypothesis.
Nevertheless, it’s plausible that canku australis also preyed on other inhabitants of its environment, such as frogs, lizards, turtles, and even mammals like Patagorrhinx pasquali, a semi-aquatic monotreme related to modern echidnas and platypuses.
During its time, canku australis coexisted with formidable carnivores like Maipu’s giant chest, a daunting megaraptorid dinosaur over 10 meters (33 feet) in length, possibly posing a threat.
The complete findings were published this week in the Journal of Vertebrate Paleontology.
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Matthias J. Motta et al. A new Unenragid from the Chorrillo Formation (Late Cretaceous, Maastrichtian), southwestern Patagonia, Argentina. Journal of Vertebrate Paleontology, published online on May 28, 2026. doi: 10.1080/02724634.2026.2656456
Source: www.sci.news
