Tricholoma acerbum (Bull. ex Fr.) Quél. Gerippter Ritterling Tricolome acerb Bitter Knight. Cap 7–12cm across, convex, margin strongly incurved, and usually ribbed, yellowish-buff to tan. Stem 30–70 x 20–30mm, bulbous and often pointed at base, apex covered in densely crowded minute yellowish granular scales, becoming yellowish-buff below. Flesh thick, white. Taste peppery and bitter, but sometimes mild, smell fruity. Gills crowded, whitish to yellowish at first becoming spotted reddish-brown. Spore print white. Spores subglobose to ovate. 4–6 x 3–4um. Habitat mixed woodland. Season autumn. Rare. Slightly poisonous although eaten in some places after parboiling; of poor quality. Distribution, America and Europe.