Overview
- The Musashitomiyo was formally described and given the scientific name Pungitius nakamuraai on Wednesday, May 27, 2026, by researchers from Kagoshima University and the National Museum of Nature and Science.
- The description appears in the Ichthyological Society of Japan’s English journal (DOI: 10.1007/s10228-026-01062-1) and is based on comparative morphological analysis against all 13 known Pungitius species.
- Scientists identified distinct skeletal features and a greater body depth that set the Musashitomiyo apart from other stickleback relatives.
- The fish is a small freshwater species of about 3.5–6 cm that lives in cold, clear spring-fed streams and today survives only in the upper reaches of the Moto-Arakawa River in Kumagaya City, Saitama Prefecture.
- The species is listed as Critically Endangered on Japan’s Red List and researchers say the accepted name should help attract international support for measures such as protecting satoyama landscape and expanding suitable stream habitat.