Agaricus benesii

Description

Agaricus benesii is an agaric mushroom of the genus Agaricus. This mushroom can be distinguished by a white cap that bruises pinkish-red when injured, a scaly lower stipe, and a conifer habitat. In age, the cap may discolor brown creating confusion with Agaricus californicus or A. xanthodermus. These species, however, have an annulus with a thickened margin, a phenolic odor, and bruise yellow, not red (quickly in the case of Agaricus xanthodermus and faintly or not at all in the case of A. californicus. Agaricus bernardii is also white and stains red, but is a larger, much stouter mushroom with a sheathing veil, and a briny odor, and typically is found in grass.

Psalliota benesii Pilát (1925) is a synonym.

Mushroom Identification

1. Cap

   4-8 cm broad, convex, broadly convex to nearly plane in age; surface white, dry, innately fibrillose, finely-scaled at the margin, discoloring brown in age; flesh, white, moderately thick, firm, turning pinkish-red when injured; odor pungent of "mushrooms", taste mild.

2. Gills

   Аree, close, pinkish-brown becoming blackish-brown in age.

3. Stem

   5-11 cm tall, 1-2 cm thick, equal, to enlarged at the base, stuffed at maturity; surface white, more or less smooth at the apex, finely scaled below; partial veil white, membranous, two-layered, upper surface striate, lower surface with scaly patches, forming a small, superior annulus; flesh white, staining red quickly when injured.

4. Spores

   5-6 x 3-4 µm, smooth, elliptical.

5. Spore Print

   Blackish-brown.

6. Habitat

   Solitary to scattered under Monterey cypress (Cupressus macrocarpus) and pines (Pinus); fruiting from mid to late winter.

Photo sources:

Photo 1 - Author: Lockhart McMann (lmcmann) (CC BY-SA 3.0)