A new finding in Argentina’s Chubut Province will rewrite our understanding of some of the biggest animals to have existed. Named Sarmientosaurus musacchioi, this new dinosaur not only hung its head like a gigantic Eeyore but also has a rare claim to fame. It is one of the few titanosaur sauropods known from a complete skull. The animal was discovered in 1997 by paleontologist Ruben D.F. Martinez. The holotype (a term that means the original body parts or illustration of a new species), of course, was the skull, and it was connected to a series of neck vertebrae. Then in 2016, a team comprising Martinez himself, Matthew Lamanna, Fernando Emiliano Novas and colleagues described and named the creature.
The animal hails from the middle of the Cretaceous, roughly 95 million years ago, and comes from a famous site known as the Bajo Barreal Formation. Other sauropods have been found here as well, but a sauropod skull is a first from this formation. The genus name of the creature honors the nearby town of Sarmiento while the species name is an homage to the late Dr. Eduardo Musacchio. Martinez and team studied the skull thoroughly, even taking several CT scans and creating 3-D models of the creature’s head to properly delve into the animal’s braincase.
The animal’s brain was small in comparison to its body, but it had massive eyeballs and probably very sharp vision, a unique discovery among sauropods. It was also able to hear very low-pitched sounds, an attribute ascertained by studies of the creature’s inner ear structure. Because of the way the dinosaur hung its head, Martinez describes Sarmientosaurus as a massive Eeyore, the depressed donkey character from the Winnie-the-Pooh stories. It held its head at a low angle, just as the fictional character does. A sauropod skull is a rare and precious finding, but a complete skull that makes artistic restoration of the animal all the more simple is an absolute exception.