First record and estimated introduction origin of the domestically introduced species Tanakia lanceolata and Acheilognathus tabira erythropterus, in Hokkaido, Japan

Abstract

We collected Tanakia lanceolata and Acheilognathus tabira erythropterus in Hokkaido, Japan, in 2017. This report represents the first record of both species in Hokkaido. Mitochondrial DNA analysis (cytochrome b region) revealed that T. lanceolata was introduced from the Sea of Japan side of the Tohoku region, while A. t. erythropterus was introduced from the Kanto region. Surveys in 2022 and 2023 have collected more than 100 specimens of T. lanceolata and confirmed that they are successfully reproducing using the freshwater mussel Inversiunio jokohamensis as a host.