Buenos Aires, 3 May 2022 (AFP) – The remains of the largest known megaraptor, between 9 and 10 meters long and which lived 70 million years ago, have been found in southern Argentina, two paleontologists who participated in the discovery told AFP. .
The fossil of the carnivorous, clawed dinosaur measuring 40 centimeters was found in March 2019, during an expedition south of the province of Santa Cruz, in Patagonia, in a region known as Estancia La Anita, 30 kilometers south of the city of El Calafate. and close to the Perito Moreno glacier.
A little over three years later, after arduous excavation work, transport to Buenos Aires, cleaning and laboratory study, which continued even with the covid-19 pandemic, the discovery of the “Maip macrothorax” has just been published in the scientific journal Nature Scientific Reports.
“It was a large animal, by the measurements we made and the comparisons. It would be one of the largest megaraptors documented so far. In addition, it is one of the last megaraptors to inhabit the planet before the extinction of the dinosaurs, which occurred about of 66 million years”, said the doctor in Natural Sciences Fernando Novas, in charge of the Laboratory of Comparative Anatomy at the Argentinian Museum of Natural Sciences, where he received the AFP team.
Novas was the one who discovered, in 1996, the first megaraptor in the Argentine province of Neuquén, also in Patagonia, but about 1,400 kilometers north of the current discovery. Later, others were found in Australia, Thailand and Japan, explained the scientist.
– Maip, ‘the top predator’ -Paleontologist Mauro Aranciaga, 29, was the one who found the first piece of the fossil of the new megaraptor, a vertebra, in 2019. “When I lifted the vertebra and saw that it had the characteristics of megaraptors , it was really a huge emotion because, in addition, I was seeing a giant vertebra. In other words, it was a giant megaraptor”, he said.
The megaraptors known so far measured between eight and nine meters in length. “This one was between 9 and 10 meters long and weighed about six tons. It is a very large and very heavy animal. It is the youngest, the largest and also the southernmost of those found in Argentina”, explained Aranciaga.
The researchers found the chest cavity, several vertebrae, some ribs, fragments of the pelvis, tail and arm. At the widest part, the chest was 1.20 meters wide by 1.50 meters high.
“This new great Patagonian carnivore represented, until the end of the [período] Cretaceous, the top predator”, explained Aranciaga. His diet included other smaller dinosaurs, which he hunted with his huge claws, capable of “capturing prey, tearing its body apart and turning between the viscera”.
Novas, in turn, noted that the fossil was found in “an extraordinary deposit, which is proving to be one of the most important we have in South America.” It is from the Cretaceous period, “when there were no [a cordilheira de] the Andes or glaciers, but tropical forests where there was an enormous diversity of beings”, he said.
The first evidence of the deposit was documented in 1980 by Argentine geologist Francisco Nulo, but the first exploration by paleontologists was in 2019, by Novas’ team.