Paleontologists uncovered fossils of a new species of long-necked, plant-eating dinosaur named Chadititan calvoi in northern Patagonia, accompanied by a diversity of fossils that suggest a unique lagoonal environment. The discovery was made in the Anacleto Formation, a fossil-rich geological area located near northern Patagonia, and was published in the journal of the Argentine Museum of Natural Sciences.
The Anacleto Formation became a treasure for paleontologists, offering detailed insight into the fauna and flora of the region during the Late Cretaceous. According to La República, excavations in rocks 78 million years old allowed the team to unearth 432 fossils from more than 100 groups of animals, revealing the richness of the fauna in an area that had not been explored so deeply until now.
Among the fossils uncovered, scientists discovered Chadititan calvoi. This new species belongs to an unusual family within the titanosaurs called the rinconsaurians, which includes Rinconsaurus and Pitekunsaurus, and is considered small compared to other titanosaurs. Chadititan calvoi measured about 10 meters (33 feet) long as an adult, whereas some titanosaurs could exceed 30 meters in length.
"It is a very particular environment, with sand dune deposits interspersed with small lakes. Just as we see today in arid places, water concentrates biodiversity," said Diego Pol, co-author of the study from the Argentine Museum of Natural Sciences. The fossils were discovered about 30 kilometers southwest of General Roca, among sediments that guarded these secrets for millions of years.
Chadititan calvoi is distinguished by its slender physique and smaller size compared to other known titanosaurs. It had features such as a thick neck leading into a sturdy chest, wide hips, and slender legs that made it more graceful than some of its bulkier relatives. The characteristics of Chadititan calvoi suggest that the subgroup of titanosaurs known as rinconsaurians may have had unusual body proportions.
"Titanosaurs include some of the last non-avian dinosaur species on the planet," said Matt Lamanna, paleontologist at the Carnegie Museum of Natural History. The study of this new species could help paleontologists understand how biodiversity changed as the world approached the end of the reign of the dinosaurs.
At the same fossil site, paleontologists uncovered the bones of a neighbor of Chadititan calvoi: an abelisaur. The abelisaur was around 6 meters (20 feet) long and equipped with a massive skull filled with sharp teeth. While Chadititan calvoi was a herbivore, the abelisaur was likely a predator.
Paleontologists also uncovered a variety of fish, including Lepisosteidae, a family of armored fish with long snouts full of sharp teeth, and Metaceratodus, a type of lungfish. The presence of these fish species suggests that Patagonia's climate millions of years ago was different from the chilly, windswept landscape known today.
Among the discoveries are fossils of a tropical land snail from the family Neocyclotidae. Paleontologists also found traces of Leptinaria, another air-breathing land snail. The traces of Leptinaria constitute the first known record of this species in the region.
Freshwater turtle fossils constitute more than 90% of the fauna found at Anacleto, a proportion never observed in contemporary sites on other continents. The prevalence of turtles suggests a humid environment, perhaps calmer than that of many other regions of the Cretaceous. The almost total absence of crocodiles compared to other contemporary geographical areas reinforces this hypothesis and emphasizes the peculiarities of the local ecosystem.
One species among the turtles is Yaminuechelys, a giant turtle with a shell stretching up to 80 centimeters (about 2.5 feet) long. Patagonia's prehistoric waters were full of life, and its residents had unique survival adaptations.
The project aims to explore the biodiversity of Patagonia at the end of the age of dinosaurs, a time marked by changes in the global ecosystem. Pol states that the understanding of ecosystems in the Southern Hemisphere near the end of the Age of Dinosaurs remains incomplete. "Herbivores play a key role, as they are the intermediaries between plants and all other links in the food chain," he said, according to La República.
The discovery of Chadititan calvoi fossils was made possible by a project funded by the National Geographic Society, in collaboration with several Argentine museums and universities, including the Museo de La Plata.
The name Chadititan calvoi refers to the excavation site and pays tribute to paleontologist Jorge Calvo. The rinconsaurians, including Chadititan calvoi, roamed the Earth between 80 and 70 million years ago, ruling Patagonia long before the asteroid crash that wiped out the dinosaurs. However, the rinconsaurians vanished millions of years before the extinction event that wiped out the dinosaurs, leaving scientists puzzled about the cause of their disappearance.
The article was written with the assistance of a news analysis system.