 |
| Figure 1. Agaricus bisporus. |
Name: Agaricus bisporus
Common Name: Common mushroom, button mushroom, table mushroom, white mushroom, Italian mushroom.
Family: Agaricaceae
Collection Date: October 31, 2011
Habitat: Solitary, scattered to gregarious near manure piles, in grass or duff under conifers, especially Monterey cypress; fruiting all months of the year when moisture is available except mid-winter.
Location: IGA in Garrettsville, Ohio.
Description: Cap 5-12 broad, convex at first with incurved margin, becoming plane in age; surface dry, with light brown, usually innate scales over a pallid ground color; flesh thick, white, typically bruising pinkish-brown to orange brown but not changing color in KOH; odor and taste mild. Gills free, pinkish-brown, becoming purple-brown, finally blackish-brown. Stipe 2-5 cm tall, 1.5-2.5 cm thick, more or less equal to slightly bulbous at base; white bruising slowly brown, smooth; veil white, cottony-membranous, forming a medial to superior ring.
Agaricus bisporus is well known to mycophagists as the common "button mushroom" of commerce. In the San Francisco Bay Area both wild forms and escapees from mushroom farms occur. Interestingly, both types look similar and cannot be distinguished without biochemical analysis. Agaricus bisporus, though not as distinctive as other Agaricus species, can be recognized by the following combination of characters: relatively short stature, cap with pale brown appressed scales, flesh which bruises slowly orange-brown to reddish- brown, but does not stain yellow in KOH, a well-developed ring, smooth stipe, and a preference for fruiting with Monterey cypress. Agaricus californicus and A. xanthodermus also occur under Monterey Cypress but the latter bruises bright yellow on the cap margin and stipe base, while the former, though similar in stature, has a distinctive double-lipped ring (best seen in fresh, young material), and stains yellow in KOH.Agaricus bisporus is sometimes also confused with A. campestris, the Meadow Mushroom, but the latter grows in grass, usually away from trees, lacks the brown cap scales of A. bisporus, has an evanescent ring, and a tapered stipe base.
Kerrigan, Richard W. (1986). The Agaricales (Gilled Fungi) of California. 6. Agaricaceae. Mad River Press: Eureka, CA. 62 p. Retrieved from http://www.mykoweb.com/CAF/species/Agaricus_bisporus.html .
Collector: Cara Tompot
 |
| Figure 2. Agaricus bisporus sliced. |
Key Used: Arora, D. (1979). Mushrooms Demystified. Berkeley, CA: Ten Speed Press.
Keying Steps:
Key to the Major Groups of Fleshy Fungi
Basidiomycetes Pg 52.
Fruiting body with a cap and stalk, or just a cap; spores borne on gills (radiating blades) on underside of cap; spore print obtainable (if spores are being produced) Agarics (Gilled Mushrooms) p. 58.
Key to Agarics:
1b. Spores forcibly discharged, hence a spore print obtainable if spores are being dispersed; gills exposed at maturity; common and widespread.
2b. Spore print some other color (pinkish, salmon, yellow-brown, brown, rusty-orange, rusty-brown, chocolate-brown, purplish, greenish, black, etc.)
10b. Spore print some shade of orange, brown (including cinnamon-brown), green, purple, gray, or black.
16b. Not as above- (above: spore print greenish to grayish-olive.)
19a. Spore print purple-brown to purple-gray, purple-black, smoky-gray, black, chocolate-brown, or deep brown.
20b. Gills free to adnexed, adnate, or occasionally decurrent.
21b. Not as above- (above: gills and/or cap auto-digesting at maturity; spore print black.)
22a. Veil present, usually forming an annulus on stalk; gills free or nearly free at maturity. Whitish to pinkish when young but becoming chocolate brown or darker in age; cap not deeply striate; spore print chocolate-brown. Agaricaceae p. 310.
Key to Agaricaceae:
1b. Odor not phenolic; base of stalk not typically staining yellow ( but may stain orange or yellow-orange), or if staining yellow then odor sweet.
1b. Odor not phenolic; base of stalk not typically staining yellow ( but may stain orange or yellow-orange), or if staining yellow then odor sweet.
7b. Not as above- (above: some part of fruiting body (especially cap surface) staining yellow when bruised and/or the flesh smelling sweet when crushed (like almond extract or anise); cap surface typically yellowing in KOH.)
25a. Flesh normally staining red to orange or vinaceous when cut or rubbed repeatedly.
26b. Not as above- (above: flesh in base of stalk staining orange to yellow-orange when cut; flesh elsewhere reddening at least somewhat; cap with broad, flattened, chocolate-brown scales, often depressed centrally at maturity; growing in woods, very rare.)
27b. Not as above- (above: unbroken veil soon brown to grayish-brown, purple-brown, or chocolate-brown to nearly black.
30b. Veil forming a skirtlike to intermediate annulus.
31a. Growing on compost or manured soil. Agaricus bisporus, p.319
Links: http://en.wikipedia.org/wiki/Agaricus_bisporus
http://www.mykoweb.com/CAF/species/Agaricus_bisporus.html
http://botit.botany.wisc.edu/toms_fungi/apr2001.html
 |
| Figure 3. Agaricus bisporus is used in many common foods such as Cream of Mushroom soup. |
 |
| Figure 4. Pizza mushrooms are another example of the many uses of Agaricus bisporus. |
 |
| Figure 5. Agaricus bisporus in Wild Mushroom soup. |
No comments:
Post a Comment