Yellow Stainer

Yellow Stainer Agaricus xanthodermus Genev. (illustrated 35% life size) Cap 5–15cm across, subspherical with the top flattened, later becoming expanded convex; white at first, later often with tiny, indistinct, greyish-brown scales, bruising bright chrome-yellow, especially towards the margin. Stem 50–150×10–20mm, bulbous at the base; white; ring white, with a thickened edge, which can cause it to appear double. Flesh white, staining chrome-yellow in the stem base; taste slightly unpleasant, smell slightly of ink. Gills white at first, becoming pale pink, finally grey-brown. Spores 5–6.5×3–4¼, elliptical. Spore print purple-brown. Cheilocystidia 10–20×8–14¼, subglobose or ovate, thin-walled, hyaline. Habitat in woods, meadows, and gardens; summer to autumn. Occasional, vulnerable on Red Data List. Poisonous with symptoms of sweating, flushing, and severe stomach cramps, but only some people are affected.