Teeth from huge tyrannosaur found in Nagasaki

Fossilized teeth from a species of giant tyrannosaurs, similar in size to the predators that wreaked havoc in "Jurassic Park," have been discovered for the first time in Japan from a stratum that dates back 81 million years.

The teeth (left and centre) were found alongside a smaller fossil, 
which is believed to be from a different species of dinosaur 
[Credit: Fukui Prefectural Dinosaur Museum]

Fossilized teeth of small tyrannosaurs have been discovered at five locations in Japan, including Fukui Prefecture, but the teeth unearthed recently in Nagasaki are newer, and their size is comparable to those of the huge species of tyrannosaur found in North America, as well as the Tarbosaurus variant in Asia.

Three theropod teeth were found in the Mitsuze strata, which was formed in the late Cretaceous Period on the western coast of the Nagasaki Peninsula, the Nagasaki city board of education and the Fukui Prefectural Dinosaur Museum announced July 14.

“The findings show there was an ecosystem led by tyrannosaurs in Nagasaki, which was connected to the Asian continent by land at that time,” said Kazunori Miyata, a senior researcher at the museum.

The largest of the three fossils measured 38 millimeters wide, 27 mm thick, and, including the tooth root, 82 mm in length.

It is most likely from the lower jaw of the predator, and the dinosaur who owned the tooth is estimated to have been more than 10 meters long.

Local researchers believe the largest piece and one of the others are from tyrannosaurs because the size and the shape of the teeth are similar to those of the huge dinosaur. The final fossilized tooth seems to be from another species of theropod.

Tyrannosaurs are believed to have roamed across North America and in China and other Asian regions in the latter half of the late Cretaceous Period (66 million years to 83 million years ago).

Author: Shoko Rikimaru | Source: The Asahi Shimbun [July 14, 2015]