Abstract
We examined specimens of the non-indigenous mytilid bivalve Mytilus galloprovincialis in the Furukawa Collection of the Fukui City Museum of Natural History. In total, 14 specimens in 4 lots were found and identified as M. galloprovincialis, all of which were collected in the 1930s and 1940s and donated by the physician Tamizo Furukawa. Two specimens collected at Hiroshima before 1934 represent the earliest collection that we know of among all the specimens of this species existing in Japan. Six specimens collected at Kanazawa, Kanagawa Prefecture in 1937, and two specimens from Obama, Fukui Prefecture before 1948 were regarded as the earliest collections that we know of among the specimens collected in Tokyo Bay and the Japan Sea, respectively. The initial invasion history and range extension of this species into the Seto Inland Sea, Tokyo Bay and the Japan Sea is discussed, focusing on the first record in each sea area.
