Fukushima researchers find 4 ammonite fossil types, including 1st in Japan

A team of researchers led by Hiroaki Inose, 38-year-old chief curator at the Fukushima Museum, has discovered four types of precious fossilized ammonites that are about 89 million years old, the Fukushima Prefecture-run museum in Aizuwakamatsu city announced on March 28. Among the fossils is one unearthed for the first time in Japan and another that had previously been undiscovered in Fukushima Prefecture. Also included is a fossil from an Ammonite Center excavation site in Iwaki city, which is open to the general public for hands-on experience. The fossil that was found in a Japan first is an approximate species of "Hyphantoceras flexuosum," previously discovered only in Europe. It constitutes a clue to tracing geographical distributions of ammonites discovered in Japan, according to the team. The fossil found in Fukushima for the first time is a "Yezoceras elegans," which was collected for the first time in Japan last year from a stratum (the Yezo group of formations) in the northernmost prefecture of Hokkaido. The latest discovery came from a stratum several million years older than the Hokkaido layer, showing that the species was alive in a wider region and during an earlier age than thought. The rest are "Yabeiceras orientale" and "Eubostrychoceras indopacificum," both of which are rarely preserved fossils. The Ammonite Center in Iwaki sits on a layer known as the Ashizawa Formation, Futaba Group. The center hosts excavation events for the public using the stratum. Yabeiceras orientale was found to have been contained in fossils unearthed there and donated to the city and the Fukushima Museum, prompting the research team to study the species in detail since spring last year. "Fossils discovered in the hands-on experience events include precious ones," said Inose. "Cooperation between researchers and public visitors has led to the discovery." The newly found fossils are scheduled to be displayed at a special exhibition, titled "Ammonite Warfare," at the museum from April 23. Photo 1: Fossil of approximate species of "Hyphantoceras flexuosum" unearthed in Japan for first time Photo 2: Fossil of "Yezoceras elegans" discovered in Fukushima for first time (Translated by Kyodo News)