The newly discovered species of dinosaur has been dubbed ‘the one that causes fear’ because of its huge size and brutal feeding habits.
Llukalkan aliocranianus was ‘scary killer’ it wandered South America about 80 million years ago, near the end of the dinosaur era.
Skull remains studied by paleontologists from the National University of San Luis in Argentina reveal a short, stunted skull and sharp teeth.
Reaching a length of five feet, he had huge claws and a keen flair for finding his prey, which he would catch while moving at speed thanks to powerful hind legs.
The species was “probably among the major predators” throughout Patagonia, now in Argentina, during the Late Cretaceous period, which stretched from 100.5 million to 66 million years ago.
It was ‘similar’ to the famous tyrannosaurs, who ruled the northern hemisphere about 80 million years ago.
Jorge Blanc’s artistic impression of Llukalkan aliocranianus. A terrifying assassin, he was ‘probably among the main predators’ throughout Patagonia, now in Argentina, during the Late Cretaceous period
Abelisauridae were a striking family of theropod dinosaurs with an average length of 16 to 30 feet that spread mainly in Patagonia and other areas of the ancient southern supercontinent of Gondwana.
Gondwana is today recognized as Africa, South America, Australia, Antarctica, the Indian subcontinent and the Arabian Peninsula.
Although abelisaurids generally resembled the T-Rex with tiny fragile arms, they had unusually short, deep skulls that often had tips, bumps, and horns.
When Tyrannosaurus and its relatives roamed North America and Asia, abelisaurids occupied a similar niche in Patagonia and other areas of South America.
The Abelisaurids had huge jaws. Just like the T-Rex, they also relied on them to crush and kill prey.
But abelisaurids had even smaller arms than tyrannosaurs.
L. aliocranianus represents not only a new species but also a new genus.
The full name comes from the original Mapuche for ‘the one who causes fear’ – (Llukalkan) and the Latin for ‘different skulls’ (aliocranianus).
It was one of 10 species of abelisaurids of known science that flourished on the southern continents.
Abelisaurids were the dominant predators in the southern hemisphere, at about the same time that tyrannosaurids roamed North America and Asia.
They were part of a wider klapa of theropods of massive bipedal carnivores with sharp claws.
‘This is a particularly important finding because it suggests that the diversity and abundance of abelisaurids was remarkable, not only across Patagonia but also in several local areas during the‘ twilight ’dinosaurs,’ said lead author Dr Federico Gianechini of the National University of San Luis Argentina.
‘This finding also suggests that there are probably more abelisaurids that we simply haven’t found yet.’
The fossilized remains of Llucalcan include an excellently preserved and untamed brain box.
They were discovered in the Bajo de la Carpa formation, in the Argentine province of Neuquén.
The most distinctive feature of the species is a small posterior air-filled sinus in the middle ear zone that has not been seen in any other abelisaurid so far.
Fossilized remains of Llucalcan include a well-preserved and uncrushed brain box (pictured) and sharp teeth
Site of discovery of Llukalkan aliocranianus, from the Bajo de la Carpa (Santonian) formation in the fossil area of La Invernada, northwestern Patagonia
The composition of the skull suggests that hearing was better than most other abelisaurids and similar to that of modern crocodiles.
L. aliocranianus also had a strange, short skull with rough bones.
In his life, his head had bumps and bumps like some of today’s reptiles, like the monster Gil.
Fossil evidence of Llucalcan adaptations suggests that abelisaurids flourished just before dinosaurs became extinct.
“These dinosaurs were still trying out new evolutionary pathways and quickly diversified just before they became completely extinct,” said co-author Dr. Ariel Mendez of the Patagonian Institute of Geology and Paleontology, Argentina.
L. aliocranianus lived in the same small area and time period as another species of abelisaurid – Viavenator exxoni – only a few million years before the end of the dinosaur era.
Researchers compared the unusual morphology of Llukalkan aliocranianus to the monster Gila (pictured) – a venomous lizard native to the southwestern United States.
The fossil remains of the two genera Llukalkan and Viavenator were found 700 meters away in the Bajo de la Carpa formation, near the same famous fossil site in La Invernada.
This new species is in many ways similar to Viavenator, except that it is smaller, and the holes in the skull through which the veins pass are larger and wider separated from the supraoccipital ridge – the bone that makes up the brain.
The study was published today in the Journal of Vertebrate Paleontology.
HOW DINOSAURS WERE EXTINCED 66 MILLION YEARS AGO
Dinosaurs ruled and dominated the Earth about 66 million years ago, before they suddenly became extinct.
The Cretaceous-Tertiary extinction is the name given to this mass extinction.
For many years, the changing climate was believed to have destroyed the food chain of giant reptiles.
In the 1980s, paleontologists discovered a layer of iridium.
It is an element that is rare on Earth, but is found in huge quantities in space.
When this was dated, it coincided exactly with the time when dinosaurs disappeared from fossil records.
A decade later, scientists discovered the massive Chicxulub crater at the top of the Mexican Yucatán Peninsula, which dates to that period.
The scientific consensus now says that these two factors are related and that both are probably caused by a huge asteroid that crashed to Earth.
With the predicted magnitude and velocity of the impact, the collision would cause a huge shock wave and likely trigger seismic activity.
Precipitation would create plumes of ash that probably covered the entire planet and made it impossible for dinosaurs to survive.
Other animal and plant species had a shorter time span between generations which allowed them to survive.
There are several other theories as to what caused the deaths of known animals.
One of the early theories was that small mammals ate dinosaur eggs, and another assumes that poisonous angiosperms (flowering plants) killed them.