Sclerotia of Typhula ishikariensis biotype B (Typhulaceae) from archaeological sites (4000 to 400 BP) in Hokkaido, northern Japan

: Despite their close association with human activities, plant pathogenic fungi have rarely been found in archaeological excavations. We report here that a fungus was closely associated with human activities even in prehistoric times. Sclerotium-like objects were found at historical sites (4000 to 400 BP) on the island of Hokkaido, northern Japan. They were spherical, 0.3-1.0 mm in diameter, and had a medulla and rind. Some had leaf fragments on the surface or a protuberance that resembled emerging sporocarp primordia. These traits indicated that they were sclerotia of the snow mold fungus, Typhula ishikariensis biotype B.