AMAKUSA, Kumamoto -- A fossilized dinosaur tooth has been found here in Kyushu in a geological layer dating back about 80 million years to the Late Cretaceous Period, it has been learned.
The announcement regarding the fossilized tooth was made by both the Goshoura Cretaceous Museum in Amakusa and the Fukui Prefectural Dinosaur Museum on July 5. The relic has an elliptically shaped cross section, and is said to resemble teeth found in the tyrannosaurid family. It has been hypothesized that the tooth belonged to a giant carnivorous dinosaur that was more than 7 meters long.
The fossil was found embedded in stone off the coast of Amakusamachi in Amakusa, Kumamoto Prefecture, in October 2014 -- when the two organizations were conducting joint research. Subsequent analysis revealed that they had found a fossilized dinosaur tooth with a length of 42 millimeters, a width of 25 millimeters, and a thickness of 16 millimeters, and judging from the surrounding traces of stone, it is thought that the tooth was at least 56 millimeters long.
A saw-like shape can be seen around the edge of the fossil, suggesting that it was a tooth in the upper left jaw or lower right jaw of a dinosaur.
In 2014, an 82-millimeter-long fossilized tooth belonging to a dinosaur in the tyrannosaurid family was found in the city of Nagasaki, which is also in Kyushu, in a geological layer that dates back about 81 million years. In addition, in Goshouramachi in Amakusa, a fossilized tooth more than 64 millimeters long belonging to a giant carnivorous dinosaur was found in 1997 in a geological layer dating back about 100 million years.
Kazunori Miyata, a senior researcher at the Fukui Prefectural Dinosaur Museum, commented on the finding in 2014 saying, "I expect that this will lead to future research that will enable us to understand the diversity of dinosaurs in Kyushu."
The fossilized tooth will be on display from July 15 at the Goshoura Cretaceous Museum, and a replica will also be exhibited at the Fukui Prefectural Dinosaur Museum.