In a revealing study, scientists from CONICET have identified a new species of dinosaur in the Argentine Patagonia, whose home dates back approximately 70 million years, at the end of the Cretaceous period. This finding took place in Salitral Moreno, south of the city of General Roca, in the province of Río Negro. The research, published in the Journal of Systematic Palaeontology, describes this new species as a small ankylosaur called Patagopelta cristata.
Discovery of the new dinosaur in Patagonia
Although the current researchers did not originally discover the bones, their analysis has allowed them to value the discoveries of other scientists since the 1980s. Although the fossils do not correspond to a single individual nor allow for the reconstruction of a complete skeleton, they have been sufficient to identify a unique species of its kind.
The ankylosaurs, known for their body armor, are herbivorous quadrupedal dinosaurs, with a dominant fossil record in the northern hemisphere. However, in the southern hemisphere, their presence is rare, with findings in places like Australia and Chile. Patagopelta belongs to the nodosaurids, a family that lacks the typical tail clubs but has spines on the neck and shoulders.
The femur of Patagopelta, the best-preserved among the remains, measures just 25 centimeters, indicating that the dinosaur reached between two and three meters in length. This classifies it as one of the smallest recorded ankylosaurs, as these animals generally measure between four and five meters.
The armor of the neck, characterized by unique spines and crests, is another distinctive element. Its protection was formed by osteoderms, similar to the current bony shields of crocodiles, arranged in lines along the back and tail.
During the late Cretaceous, a continental bridge allowed the exchange of fauna between North and South America. This explains the presence of nodosaurids in South America, where remains like those of Patagopelta are expected to be found just before the mass extinction of the dinosaurs.
The dwarfism, possibly related to the island rule, may explain the small size of Patagopelta. This theory suggests that in insular ecosystems, where resources are limited, living beings tend to become smaller. At that time, the Kawas Sea invaded northern Patagonia, fragmenting the habitat and favoring such evolutionary adaptations.
This discovery not only expands our knowledge of ankylosaurs but also enriches the discussion about their biology and the conditions that favored dwarfism in this unique dinosaur species.
