Photo/Illutration A piece of fossilized bone from a pterosaur found in Nagashima, Kagoshima Prefecture, seen from various angles (Provided by Nagashima's board of education)

NAGASHIMA, Kagoshima Prefecture--A fossil of a pterosaur, a flying reptile from about 100 million years ago, has been discovered in Kagoshima Prefecture for the first time, according to Nagashima’s board of education.

It was found near the site where a plesiosaur fossil was unearthed in 2004, the board of education announced on Aug. 26.

A research team said the two fossilized species are some of the oldest in East Asia to have ever been found in adjacent layers of earth.

The cylindrical pterosaur fossil, nicknamed “Satsuma-Yokuryu,” measures roughly 7 centimeters long and 2.3 cm thick.

Satoshi Utsunomiya, a Panasonic Corp. employee who lives in Higashi-Osaka, Osaka Prefecture, discovered it in the Goshoura strata from the Cretaceous Period (about 100 million years ago) on the coast of Shishijima island in Nagashima, Kagoshima Prefecture, on Nov. 19, 2020.

“I initially thought it was an ammonite fossil, so I was surprised to learn that it is actually a fossilized pterosaur,” said Utsunomiya. “I nicknamed it Satsuma-Yokuryu because I want it to become widely known among local residents.”

Satsuma was a former name for the domain of what is now Kagoshima Prefecture.

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A replica of a pterosaur ((c) Kaiyodo)

A team of researchers, including Yasuhisa Nakajima, an associate professor of paleontology at Tokyo City University, re-examined the fossil and determined that it is part of a foreleg in a wing or a hind leg of a pterosaur.

“The discovery will provide a clue to the ecosystem of the Pacific Ocean around the mid-Cretaceous Period, when it was a very warm climate,” Nakajima said in an online news conference.

A CT scan revealed that the fossil is covered with a 1-to-2-millimeter-thick bone and filled with fossilized mud. The bone is thought to have originally been hollow and light, back when the pterosaur was alive.

The species is believed to be as large as Anhanguera, a pterosaur from the same period, which had a wingspan of about 4 to 5 meters.

Utsunomiya, 51, has unearthed many fossilized species, including dinosaurs, and published the findings.

In 2004, he discovered a fossil of “Satsuma-Utsunomiyaryu,” the first fossilized plesiosaur ever found in the Kyushu region, in a stratum about 20 meters from the site where he unearthed the pterosaur fossil.

The fossil will be donated to the town of Nagashima and is expected to be put on permanent display at the Kagoshima Prefectural Museum in Kagoshima city.