Newfound "King of Gore" Dinosaur Ruled Before T. Rex
The ancient tyrannosaur resembles T. rex and was found in the Southwest.
At 24 feet (7.3 meters) long and weighing about 2.5 tons, the 80-million-year-old Lythronax (pronounced LYE-thro-nax) lacked the even-more-massive size of T. rex, says the University of Utah's Mark Loewen, who headed the team reporting the dinosaur's discovery in PLOS One.
In comparison, T. rex was about 40 feet (12 meters) long and about 15 to 20 feet (4.6 to 6 meters) tall. (See also "My T. Rex Is Bigger Than Yours.")
"Obviously we wanted to get 'king' in the name," Loewen says. "Lythronax wasn't a direct ancestor of T. rex, but they clearly shared a common ancestor, [one] who lived even longer ago."
That means that western North America, then a separate continent called Laramidia that stretched from Alaska