Breaking: New Dinosaur Is Smallest Known Titanosaur From Central Patagonia

A team of Argentinian researchers and paleontologists working in the La Colonia Formation of central Patagonia, uncovered the fossil remains of a new titanosaur in rocks dated to 70 million years old. Published today in Biological History, the dinosaur was named Titanomachya gimenezi in homage to the late Dr. Olga Giménez, who was the first female paleontologist to study the dinosaurs of the Chubut province in which the La Colonia Formation is located.

Titanomachya gimenezi marks the first sauropod dinosaur discovery recognized in the La Colonia Formation and is only the second saltasauroid recorded south of the North Patagonian Massif. It is also the smallest known titanosaur from central Patagonia having weighed an estimated 7 tons — about 10 times smaller than its giant titanosaur counterparts.

Credit Vincent Brusca

The dinosaur was unearthed as part of a project on the end of the dinosaur era in Patagonia led by National Geographic Explorer Diego Pol and supported by the National Geographic Society along with more than ten museums and universities from Argentina, including the Museo de La Plata and the Museo Paleontológico Egidio Feruglio.

Researchers were able to identify the dinosaur from the recovery of forelimbs, hindlimbs and fragments of ribs and a caudal vertebra. From these specimens, they were able to determine Titanomachya’s unique morphological characteristics amongst Upper Cretaceous titanosaurs.

For example, the structure of the Titanomachya’s astragalus (a major bone in the ankle), has never before been seen in other titanosaurs and demonstrates a significant intermediary evolutionary trait between Colossosauria and Saltasauroidea — the two major branches of the titanosaur family tree. As such, Titanomachya occupies a significant place in the evolutionary landscape of sauropod dinosaurs in Patagonia during the Late Cretaceous Epoch.

“The discovery of Titanomachya, adds to previous data suggesting there was a major ecological change as the Cretaceous [Period] was coming to an end, marked by the downsizing of titanosaurs, a decrease in their abundance, and the predominance of other herbivorous dinosaurs, such as hadrosaurs on the landscape. This ecological shift in herbivorous dinosaurs occurred amidst changing climates and habitats, as well as the advance of the Atlantic Ocean over large parts of Patagonia,” said National Geographic Explorer Diego Pol.

The project aims to broaden our scientific understanding of dinosaurs and vertebrates that existed throughout Patagonia during the last 15 million years of the Cretaceous Period in hopes to build a database to help researchers identify extinction patterns in South America relative to other regions of the world.

“We are thrilled to share in the exciting discovery of Titanomachya gimenezi that Diego and this great team of researchers and field and lab technicians have worked to uncover. It is a true testament to what we are dedicated to doing every day at the National Geographic Society — engage in science and exploration to better understand the wonder of our world and share those findings with the global community,” said Ian Miller, the National Geographic Society’s Chief Science and Innovation Officer.