Agaricus placomyces
Agaricus placomyces is a toxic basidiomycete fungus of the genus Agaricus. It is found in North America; the Eurasian populations formerly known by the same scientific name are nowadays known as A. moelleri, while the present species may also be referred to as A. praeclaresquamosus.
Description
Agaricus placomyces has a cap that is wide and varies from convex to broadly convex or nearly flat in age. In addition, the surface of the cap is dry and covered with brownish fibers and scales, especially over the center. Underneath, the cap can be whitish under normal environments, or pinkish in wet weather. Covered with fine, appressed greyish-brown scales and concentrated at the disc, the cap is thick, slowly becoming vinaceous when injured; the odor smells of phenol. The flesh is white, and becomes yellow when placed in KOH.The gills of this mushroom are free from the stem, crowded, and pale grayish-pink, turning brown in age. In addition, the stem is 6–15 cm long, 1–1.5 cm. thick and more or less equal, with an enlarged base. Also, it is fairly smooth, white and bruising yellow, especially at the base, with a persistent ring, and the partial veil when still covering the gills developing brownish to yellowish droplets.
At 8–15 cm long and 2–3.5 cm thick, the stipe is slightly enlarged at the base; the surface is white, and smooth above and below the ring. The veil of the stipe is membranous, thick, white, and forms a persistent ring with a smooth upper and lower surface. The base of the stipe is typically yellow when bruised and smells of phenol.
The spores are 4–6.0 x 3.5–4.5 μm, smooth, and elliptical; the spore print is dark brown.