The Tyrannosaurus rex may be among the most well-known and terrifying dinosaurs to walk the Earth, but a newly discovered relative may have been even scarier.
Dynamoterror dynastes, a variant of T. rex, was discovered in New Mexico in 2012 by a team of researchers, led by Western Science Center paleontologist Andrew McDonald. It has a slightly different bone structure compared to its successor cousin.
"Despite fragmentation of much of the axial and appendicular skeleton prior to discovery, the frontals, a metacarpal, and two pedal phalanges are well-preserved," the study's abstract reads. "The frontals exhibit an unambiguous autapomorphy and a second potential autapomorphy that distinguish this specimen from all other tyrannosaurids."
D. dynastes, which means "powerful terror ruler," lived approximately 80 million years ago, significantly older than many T. rex fossils which have already been found. The large majority of T. rex fossils that are already in museums are between 66 million and 77 million years old, the study added.
The study was published in PeerJ, a scientific peer-reviewed journal.
The fossils were found in the Menefee Formation of New Mexico, part of the ancient continent Laramidia, which later became North America.
The bone fragments provided challenges to the researchers, but they were able to utilize 3D scanning and printing to figure out that it was a therapod, even if they weren't sure it was carnivorous, initially. "Laser-scanning the frontals and creation of a composite 3-D digital model allows the frontal region of the skull roof of Dynamoterror to be reconstructed," the abstract adds.
“We could tell that it was a large theropod from the large fragments of hollow limb bones,” McDonald told Smithsonian Magazine.
Speaking with Gizmodo, McDonald said: “There are features on the right frontal that aren’t preserved on the left, and vice versa. But there are enough overlapping features” which allowed the researchers to have "landmarks to work with.”
The finding of D. dynastes comes days after the discovery of Ledumahadi mafube, the largest animal that walked the Earth during its lifetime, was made public.
Ledumahadi mafube, which means "a giant thunderclap at dawn," in the South African language Sesotho, walked in an unusual way. It did not walk on straight limbs, but rather with a "crouched" stance, causing scientists to believe L. mafube was an "evolutionary 'experiment'."
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