Photo/IllutrationThis specimen, measuring 2.5 centimeters wide and 1.5 cm tall, contains a fossil of a new albanerpetontid amphibian species, with bones visible near the center. (Provided by the education board of the city of Hakusan, Ishikawa Prefecture)

  • Photo/Illustraion

HAKUSAN, Ishikawa Prefecture--A fossilized amphibian found here has been identified as a new species of the Albanerpetontidae family, which was wiped out an estimated 3 million years ago, city officials said.

The fossil was discovered in the Kuwajima fossil cliff, a central government-designated “natural monument” datable to the early Cretaceous period around 130 million years ago.

It is the first albanerpetontid fossil found in Japan and represents the earliest record of the extinct amphibian family in Asia, officials of the Hakusan board of education said April 6.

The fossil was studied by Susan Evans, a professor of vertebrate morphology and paleontology with University College London, and Ryoko Matsumoto, a curator with the Kanagawa Prefectural Museum of Natural History.

The scientists said albanerpetontids are land-living amphibians that are believed to have emerged between 160 million and 65 million years ago and gone extinct 3 million years ago.

Resembling the salamander, they have been found in fossil form in North America, Europe and Uzbekistan.

A CT scan of the specimen found in the Kuwajima fossil cliff showed 43 pieces of bones, including those of the head, the spine and a hind limb. The fossil was attributed to an albanerpetontid based on the shape of the lower jaw and other features.

The fossilized animal has an estimated body length of 60 millimeters, which makes it smaller than individuals of the 12 known albanerpetontid species. Its frontal bone also has a distinct shape. These and other features led the scientists to conclude that it represents a new species.

The researchers named the species “Shirerpeton isajii” in honor of Shinji Isaji, who heads the Tetori Group fossil investigation commission, a body under the Hakusan city government in charge of studying the Kuwajima fossil cliff.