Agaricus arorae

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Agaricus arorae
Arorae.JPG
A pair of Agaricus arorae
Scientific classification edit
Kingdom: Fungi
Division: Basidiomycota
Class: Agaricomycetes
Order: Agaricales
Family: Agaricaceae
Genus: Agaricus
Species:
A. arorae
Binomial name
Agaricus arorae
Kerrigan

Agaricus arorae is a moderate-sized, forest-dwelling mushroom that exhibits distinctive color changes. It fruits early in the mushroom season. Unusually within the genus Agaricus, the mushroom's cap cuticle turns yellow when exposed to a base such as potassium hydroxide or sodium hydroxide but stains red when cut.[1] In the field, it has a brownish, fibrillose/squamulose cap, which turns red when bruised. Agaricus arorae was first described from Santa Cruz County but since has been found in San Mateo and Alameda counties.[2][3][4] Agaricus arorae can be distinguished by its scales and a conspicuous stipe.[5]

Agaricus arorae was named after American mycologist and author David Arora.

Description[edit]

Pileus[edit]

The cap is 3–8 cm broad, and varies from hemispheric to convex. The margin starts curved, but then decurved. The cuticle slowly bruises a reddish colour, and yellows with KOH. With a dry surface, the cap's disc can be glabrous or tomentose. Toward the margin, either minute fibers or scales develop. The cap's fibrils are generally a brownish colour. The cap has an indistinct odor with a mild taste. The context can be as large as 5 mm thick, soft, and bruises irregularly a vinaceous colour where cut.[6]

Lamellae[edit]

The gills are free, close, and broad. At first, they are buff-brown, but turn a darker brown in age.

Stipe[edit]

The stipe is 4–9 cm long and 0.5-2.5 cm thick. At the base, it is slightly enlarged and becomes stuffed at maturity. The white veil is rather membranous and yields a thin ring. When cut, the cortex discolours to pinkish-orange. The stipe base changes brown to rusty-brown from handling. The margin is sometimes light brown. The apex surface is white, and patchy fibrillose over a dull-buff ground color.[7]

Spores[edit]

Spores are 4.5-5.0 x 3.0-3.5 µm, elliptical, and inequilateral in profile. In addition, they are moderately thick-walled, lacking a germ pore.[8]

See also[edit]

References[edit]

  • Arora, David (1986). Mushrooms Demystified (2 ed.). Ten Speed Press. Agaricus arorae.
Specific
  1. ^ Arora, p. 313, p. 326
  2. ^ Kerrigan, Richard W. (1985)
  3. ^ Arora, p. 311
  4. ^ Studies in Agaricus III. New species from California. Mycotaxon 12: 419-434.
  5. ^ Kerrigan, Richard W. (1986). The Agaricales (Gilled Fungi) of California. 6. Agaricaceae. Mad River Press: Eureka, CA. 62 p.
  6. ^ Wood, Michael; Fred Stevens (1998). "Bovista aestivalis". Retrieved 2009-07-07.
  7. ^ Arora, p. 325-326
  8. ^ Arora, p. 320