Three fossilized dinosaur tooth fragments have been discovered in a layer of earth 81 million years old in Nagasaki Prefecture, researchers said Monday.
One of the three is from an ankylosaur, a bony-plated herbivore from the Upper Cretaceous period, estimated to be 5 to 8 meters in length, the joint team from the Fukui Prefectural Dinosaur Museum and the city of Nagasaki's board of education said.
The 10 mm by 9 mm tooth is the fourth discovery of fossilized remains, excluding a footprint, of an ankylosaur in Japan, according to the team. The others were found in Hokkaido, Hyogo, and Kumamoto prefectures.
The carnivorous dinosaurs the two other fossilized tooth fragments came from haven't been identified.
Kazunori Miyata, a curator at the Fukui museum, said the discovery of more than one fossil from the same layer is rare.
"Nagasaki Prefecture could be a center for fossil studies in Japan," he said.
The three fragments will be exhibited in Nagasaki for three days starting Tuesday and at the Fukui museum from Aug. 4 to mid-September.