Northernmost record of the amphidromous sleeper, Eleotris fusca, collected using Ishikura-net from the Tomioka River, Fukushima Prefecture, Japan

A single specimen of the amphidromous sleeper, Eleotris fusca (Schneider, 1801), was collected using Ishikura-net, which consists of dozens to hundreds of stones piled that are enveloped by a large-mesh cage, from the Tomioka River, Fukushima Prefecture, Japan. This species has been found in freshwater areas including river tidal reaches, mainly in the tropical-subtropical zones of the Indo-Pacific region. In Japan, two specimens have been recorded from a river in Iwaki, Fukushima Prefecture as the northernmost record. The present specimen represents the second record of E. fusca from Fukushima Prefecture as well as its new northernmost record.