An article published in the journal “Acta Palaeontologica Polonica” reports the identification of a species of titanosaur that lived about 95 million years ago, in the Cretaceous period, in today’s Argentina and was named Bustingorrytitan shiva. María Edith Simón and Leonardo Salgado examined the partial skeletons of four specimens discovered in the village of Villa El Chocón, in the Neuquén province of Patagonia. This area of Argentina was home to various species of titanosaurs, the largest animals to have lived on land.
The top image (Courtesy María Edith Simón and Leonardo Salgado) shows the forelimb bones of one of the Bustingorrytitan shiva specimens discovered.
In recent decades, various titanosaurs have been discovered in Patagonia. In August 2017, an article published in the journal “Proceedings of the Royal Society B” described the study of what the authors estimated was the most massive titanosaur discovered so far, named Patagotitan mayorum. Subsequent estimates indicated a weight of between 55 and 57 metric tons versus the initial 69 and discussions are still ongoing. Now this new study proposes another candidate to get closer to what could be the maximum possible limits for these dinosaurs.
María Edith Simón and Leonardo Salgado attributed the Bustingorrytitan shiva to the Lithostrotia group, which is also at the center of discussion because it’s difficult to define with reasonable certainty the relationships between the various species of titanosaurs. Sometimes the term Lithostrotia was used as a synonym for Titanosauria, complicating the issue. The problem always lies in the limited availability of fossils, with the consequence that each new discovery can call into question the definitions and structures of various taxonomic groups.
According to the two researchers, Bustingorrytitan shiva could reach a weight of around 67 metric tons and this would make it one of the most massive discovered. However, this is still a rather rough estimate due to the incompleteness of the skeletons, which adds uncertainties. For this reason, subsequent studies could provide a very different estimate.
Doubts about Bustingorrytitan shiva’s weight could mean that this dinosaur wasn’t actually that colossal, just as seems to have happened with Patagotitan mayorum. It must be said that new estimates may indicate that Bustingorrytitan shiva was even more massive than initially estimated.
The discovery of Bustingorrytitan shiva offers new information about the titanosaurs that lived in today’s southern Patagonia during the Cretaceous period. Fossils of this species were found in the same area as two other titanosaurs: Argentinosaurus huinculensis and Chucarosaurus diripienda. The differences found between these species indicate that different groups lived in the same area at the same time. This shows a remarkable diversification also considering less colossal species of dinosaurs related to the known titanosaurs.
The discovery of various not closely related titanosaurs indicates that the level of gigantism present in Bustingorrytitan shiva emerged independently in separate groups of sauropod dinosaurs. The fact that various titanosaur species emerged in today’s southern Patagonia suggests that there were environmental conditions that favored the growth in size of various sauropod dinosaurs. Studies continue to reconstruct the ecosystem in which they lived and the evolution of these colossal animals.