1st Mukawaryu Dino Replica Preps for Full-Body Experience at New Museum

The Yomiuri Shimbun
The first Mukawaryu dinosaur replica is exhibited without its tail at the Hobetsu Museum in Mukawa, Hokkaido.

MUKAWA, Hokkaido — The first replica of a dinosaur fossil referred to as Mukawaryu, or dragon of Mukawa, has been exhibited as an incomplete skeleton but is expected to be displayed in its complete state as early as spring 2026 at a new museum to be built in Mukawa, Hokkaido.

Mukawaryu has also been called “The Perfect” because the bones from the whole body were perfectly fossilized. However, the first replica of the fossil was displayed without its tail at the Hobetsu Museum in Mukawa for years due to the small exhibition space.

In 2024, which is the Year of the Dragon, the town is expected to sign a design contract for the new museum.

The Mukawaryu tail fossil was found in the city in April 2003, followed by other parts of its skeleton, until the whole body of the 8-meter-long dinosaur was uncovered. Finding a fossil in such a state is unusual in Japan and officials started referring to it as “The Perfect.”

The first replica was completed in 2019 and was put on display at a special exhibition at the National Museum of Nature and Science, Tokyo in July 2019, where it became an instant hit. Feeling encouraged, the town made a second replica, which was created to lease to other institutions, in 2020.

The second replica was displayed at dinosaur exhibitions both inside and outside Hokkaido. It is currently on display at the Aoao Sapporo aquarium in Sapporo.

The Yomiuri Shimbun
The second Mukawaryu dinosaur replica is displayed at the Aoao Sapporo aquarium in Chuo Ward, Sapporo.

The first replica has been on display in a 99-square-meter room at the Hobetsu Museum. It was known that it would be impossible to display the entire skeleton, so the town planned to redevelop the area around the museum and relocate the first replica in spring 2022 to the new museum. However, Mukawa was affected by the Hokkaido Eastern Iburi Earthquake in September 2018, causing redevelopment plans to be shelved.

The project restarted in 2022, finally taking a step closer to the entire skeleton of the first replica to be displayed, four years later than originally planned.

Mukawaryu is what the fossil is commonly referred to as, but its scientific name is Kamuysaurus japonicus, meaning “Japanese dragon god.” It was determined to be a new species of hadrosaurid in 2019. It is the largest full-body fossil of a dinosaur discovered in Japan, and over 80% of its body in terms of volume was found preserved.