20/06/2026 09:33 - Actualidad
Reconstrucción paleoartística de Antusuchus rionegrinus, cocodrilo terrestre del tamaño de un perro mediano caminando sobre dunas del Desierto de Kokorkom en la Patagonia del Cretácico, hace 100 millones de años, con paisaje desértico y dunas de arena al fondo, colores cálidos estilo ilustración científica
A team of Argentine researchers led by Dr. María Lucila Fernández Dumont from the Fundación Azara has identified a new species of fossil crocodile at the La Buitrera Paleontological Area, located approximately 20 kilometers south of Bariloche, in Río Negro Province. The discovery was published in the scientific journal Historical Biology and represents a significant contribution to understanding the evolution of Southern Hemisphere ecosystems.
The new species was named Antusuchus rionegrinus, honoring the province where it was discovered. This terrestrial crocodile inhabited the region over 100 million years ago, during the Cretaceous period, when the largest dinosaurs ever to exist dominated the planet and Patagonia presented a radically different landscape than today.
La Buitrera is one of Argentina's most important paleontological sites, studied for over 25 years by Dr. Sebastián Apesteguía and his team. The site is located on a hill near Bariloche, a famous tourist destination in Argentine Patagonia known for its lakes and mountains.
The area's name comes from the vultures (buitres in Spanish) that frequent the zone. Its importance lies in the exceptional preservation of specimens found there, allowing scientists to reconstruct complete ecosystems from the geological past.
Approximately 100 million years ago, Patagonia presented a completely different landscape from today. In the region now occupied by the provinces of Río Negro and Neuquén, a vast desert of mobile dunes extended, known as the Kokorkom Desert, shaped by winds under a warm, arid climate.
This desert environment hosted diverse fauna including giant dinosaurs and various terrestrial crocodiles adapted to life on land, very different from their modern relatives that depend on water bodies.
Peirosaurids are an extinct group of terrestrial crocodiles that were widely distributed across southern continents during the Cretaceous period. Unlike modern crocodiles, which are primarily aquatic ambush predators, peirosaurids were adapted to terrestrial life and possessed anatomical features that allowed them to move efficiently on land.
The discovery of Antusuchus rionegrinus provides key information about the origin and diversification of this group in South America, demonstrating that Patagonian Cretaceous ecosystems were more complex than previously thought.
The research was based on two specimens found near La Piedra Sola, within the La Buitrera Paleontological Area. The fossils underwent a rigorous study process:
Until now, the most characteristic crocodiles from La Buitrera Paleontological Area were uruguaysuchids, represented by abundant species such as:
These crocodiles primarily fed on insects, seeds, and other resources available in the desert environment. The discovery of Antusuchus rionegrinus as a specialized predator indicates the ecosystem was more complex than believed, with different ecological niches occupied by diverse crocodile groups.
The discovery was accompanied by the Secretary of Culture of Río Negro, as the authority responsible for heritage control. Technical teams from Heritage and Museums work on protecting, registering, and safeguarding paleontological assets, in compliance with Provincial Law 3041, which regulates interventions at such sites.
This discovery confirms the relevance of La Buitrera site and its potential to continue providing fundamental information about the evolution of South American ecosystems, positioning Argentine paleontology at a global level.
Source: Economicas Bariloche
Alfredo S. Quiroga
