A lower jawbone fossil from a tyrannosaurid dinosaur was found in a roughly 74-million-year-old layer of earth from the Late Cretaceous period in Kumamoto Prefecture, the first such discovery in Japan, local museums said Thursday.
The finding in Reihoku is expected to advance studies regarding the classification of large theropods during the Late Cretaceous period and the range of its habitat within Asia, according to the Goshoura Cretaceous Museum and the Fukui Prefectural Dinosaur Museum.
The fossil is believed to belong to a new species in the Tyrannosauridae family, with an estimated body length of about 8 meters, according to a researcher at the dinosaur museum.
The fossil was initially discovered in 2014. Of the lower jawbone, the left dentary bone, which supported its teeth, measures around 14 centimeters in length and about 8 cm in height, while the connecting right side is approximately 17 cm in length and around 8 cm in height.
It is the largest jawbone of a carnivorous dinosaur discovered in Japan, according to experts.
"It was found from younger strata compared with fossils discovered in the past. It is a rarity in Asia," said Hiromi Kurosu, a curator of the Goshoura museum.
The jawbone fossil will be exhibited at the museum following its opening in March following renovations.
Members of the Tyrannosauridae family were large carnivorous dinosaurs with a body length of about 5 meters to over 10 meters that roamed present-day North America and Asia about 83 million to 66 million years ago, according to the museum.
Fossil teeth of the dinosaur group have been discovered in areas such as Nagasaki.