FUKUSHIMA (Kyodo) A fossilized claw belonging to a large crawfish dating from the late Jurassic period, about 150 million years ago, has been found in a layer of earth in Minamisoma, Fukushima Prefecture, a museum curator said Saturday.

The fossil is one of the largest reported so far in the world and could be a newly discovered species, said Hisayoshi Kato, a curator at the Natural History Museum and Institute run by the Chiba Prefectural Government.

Kato evaluated the claw, measuring 11.4 cm long and up to 2.1 cm wide, after it was found in July last year by Ayumu Tadano, 13, who was part of a group of amateur fossil collectors digging in the layer.

"There have been reports of unearthing such large species from the mid-Cretaceous period, but none have been found from the Jurassic, either in Japan or abroad," Kato said, adding that fellow experts also recognized the sample as being extremely large when he presented it at a symposium in Germany in June.

It is difficult, however, to identify the species as other parts of the crawfish have not been found, he said.

The fossil will be kept stored at the Minamisoma Museum.

Tadano was an elementary school pupil when he found the fossil last year.