Arackar licanantay: New Titanosaur Species Unearthed in Chile

Tuesday, April 27, 2021

Life reconstruction of Arackar licanantay. Image credit: Mauricio Álvarez.

A new genus and species of lithostrotian titanosaur has been identified from a partial skeleton found in northern Chile.

Arackar licanantay lived in what is now the Atacama region of Chile during the Late Cretaceous epoch, between 84 and 66 million years ago.

The species belongs to Lithostrotia, a large group of derived sauropod dinosaurs in the clade Titanosauria.

“The Titanosauria is very broad and diverse, with repeated finds in what is now Argentina and Brazil,” said Dr. David Rubilar-Rogers, a paleontologist at the Museo Nacional de Historia Natural in Chile.

“However, it is much less frequent to find them on this side of the mountain range.”

“There are very few records of titanosaurs in this territory, which makes Arackar licanantay a very valuable find.”

The partial skeleton of Arackar licanantay, including cervical and dorsal vertebrae, humerus, femur and ischium, was recovered from the Hornitos Formation in northern Chile.

It is the most complete sauropod dinosaur recorded in Chile and the south Pacific margin of South America.

It is also the third dinosaur named from Chile, after Atacamatitan chilensis and Chilesaurus diegosuarezi.

Arackar licanantay is a new lithostrotian titanosaur represented by associated and disarticulated bones that belong to a single sub-adult specimen of around 6.3 m (20.7 feet) long,” the paleontologists said.

“This sauropod is diagnosed by a unique association of features of dorsal vertebrae and appendicular bones.”

“It shares some characters with Rapetosaurus and Bravasaurus, and do not belong to the derived clade Saltasaurinae from Patagonia.”

“Another peculiarity of Arackar licanantay is related to the disposition of its limbs,” said Dr. Alexander Vargas, a paleontologist at the Universidad de Chile.

“A characteristic of many titanosaurs is that their legs were at an open angle. The new dinosaur does not have that angle, it is quite straight compared to the femur of other titanosaurs.”

The team’s paper was published in the journal Cretaceous Research.


David Rubilar-Rogers et al. 2021. Arackar licanantay gen. et sp. nov. a new lithostrotian (Dinosauria, Sauropoda) from the Upper Cretaceous of the Atacama Region, northern Chile. Cretaceous Research 124: 104802; doi: 10.1016/j.cretres.2021.104802