Abstract
A pest of cultivated shiitake mushroom Chaetosciara takahashii Sasakawa, 1992 (Diptera: Sciaridae) originally described on Hachij Island, Tokyo was recently recorded in Shizuoka, Miyagi and Iwate Prefectures, mainland Japan. The Palaearctic congeners C. estlandica (Lengersdorf, 1929) and C. umbalis Mohrig and Krivosheina, 1990 were recorded in Japan for the first time.