A duo of paleontologists in Argentina has identified a new genus and species of gigantic titanosaur from several fossilized specimens found in the Patagonian province of Neuquén.
Life reconstruction of Bustingorrytitan shiva. Image credit: UnexpectedDinoLesson / Holger Detje / Sci.News.
Bustingorrytitan shiva lived in what is now South America during the Cenomanian age of the Late Cretaceous epoch, approximately 95 million years ago.
“Titanosaurs include the largest terrestrial animals that ever lived,” said María Edith Simón and Leonardo Salgado, authors of a paper in the journal Acta Palaeontologica Polonica.
“Five species, four of which inhabited Patagonia, would have reached body masses of 50 tons or more: Patagotitan mayorum, Argentinosaurus huinculensis, Notocolossus gonzalezparejasi, not from Patagonia but from the Neuquén Basin, Puertasaurus reuili, and Dreadnoughtus schrani.”
“However, only one of these, Dreadnoughtus schrani, preserves a humerus and femur from a single individual, with the possibility to estimate the body mass by means of scaling equations, which are robust predictors of body mass in quadrupedal tetrapods.”
Bustingorrytitan shiva was a member of Lithostrotia, a large group of titanosaur sauropods that lived during the Cretaceous period.
“The phylogenetic analysis performed recovers Bustingorrytitan shiva as a lithostrotian, the sister taxon of Saltasauridae,” the paleontologists said.
The fossilized remains of at least four individuals of Bustingorrytitan shiva were collected from the base of the Huincul Formation at the Bustingorry II site in Villa El Chocón, Neuquén province, Argentina.
The material consists of a relatively complete skeleton, and three other incomplete specimens.
“Bustingorrytitan shiva comes from the same stratigraphic unit as the basal colossosaur Chucarosaurus diripienda and the lognkosaur Argentinosaurus huniculensis, the first gigantic titanosaur to be described,” the researchers said.
Bustingorrytitan shiva has an estimated body mass of 67.3 metric tons, which makes it one of the largest sauropod dinosaurs ever recorded.
“Gigantic titanosaurs were an important component of the Cretaceous dinosaur faunas of Patagonia, at least for almost 50 million years,” the scientists noted.
“The discovery of Bustingorrytitan shiva increases our knowledge of these extraordinary animals, not only in terms of their anatomical diversity but also their evolutionary history.”
“The early Late Cretaceous is a particularly important time for the evolutionary history of sauropods, both globally and regionally.”
“Particularly, the time represented by the base of the Huincul Formation is relevant for its diversity of sauropods: mid to large-sized titanosaurs, small to mid-sized basal diplodocoids, and gigantic titanosaurs such as Bustingorrytitan shiva.”
“The sauropod diversity in the Cenomanian-Turonian interval (100 to 90 million years ago) in the Neuquén Basin, expressed not only in terms of body size but also in terms of dental morphology, may have been possible by a process of niche partitioning.”
“Towards the Cenomanian-Turonian boundary (94 million years ago), a global faunal turnover marked the extinction of basal diplodocoids and of certain lineages of titanosaurs, as well as of other dinosaur groups.”
“However, some saltasauroid and lognkosaur lineages exceeded that limit, surviving until practically the end of the Cretaceous.”
“Among the latter are the gigantic titanosaurs, such as Notocolossus gonzalezparejasi.”
“So far, latest Cretaceous gigantic titanosaurs are limited to southern Patagonia,” they added.
“Although northern Patagonia has been explored more extensively and for much longer, no gigantic titanosaurs have been recorded.”
“Of course, this hypothesis could be discarded with new findings, but a local extinction of gigantic titanosaurs from northern Patagonia in pre-Campanian times should not be ruled out.”
“The record of Bustingorrytitan shiva corroborates the idea that gigantism (evolution of forms over the 50 metric tons) would have evolved many times within Eutitanosauria,” they said.
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María Edith Simón & Leonardo Salgado. 2023. A new gigantic titanosaurian sauropod from the early Late Cretaceous of Patagonia (Neuquén Province, Argentina). Acta Palaeontologica Polonica 68 (4): 719-735; doi: 10.4202/app.01086.2023
