Fossil teeth of a plant-eating dinosaur have been discovered in southwestern Japan, offering fresh clues about the reptile and the ecological system some 81 million years ago, a local museum said Tuesday.

Thirty-five fossil teeth have been unearthed from a geological layer of the late Cretaceous period on the west bank of Nagasaki Peninsula, according to the Fukui Prefectural Dinosaur Museum and the city of Nagasaki.

The teeth are believed to be of a herbivore similar to the hadrosaur, or duck-billed dinosaur, which is known to have had a dense array of flat teeth for chewing.

Of the 35 teeth, 34 were found within a radius of several meters, the museum said.

"We can assume there were a number of dinosaurs in the area. If fossils of plants and animals are found nearby, we can replicate the ecosystem of that time," an official of the museum said.

The height of the biggest tooth found was about 1.7 centimeters and it had a width and thickness of around 1 cm.

As the surface of each tooth was either flat or dented, and the roots were not dichotomous, the museum judges the fossils to belong to an ornithopod grazing dinosaur.

When an ornithopod's teeth wore down, they are believed to have fallen out naturally and been replaced by new teeth.

The fossils will be showcased at the Gunkanjima Museum in the city of Nagasaki for four days from Thursday and at the Nagasaki Science Museum from July 25 to Sept. 18. Six replicas will be displayed at the Fukui museum from Wednesday.

In Japan, fossils of similar dinosaurs have been excavated in six other prefectures including Iwate and Fukushima prefectures and the complete skeleton of a Hadrosaurid was unearthed in Mukawa, Hokkaido.