Lyophyllum decastes

[ Basidiomycetes > Agaricales > Tricholomataceae > Lyophyllum . . . ]

by Michael Kuo

I don't know how many mushroom species are hiding out under the name "Lyophyllum decastes," but it wouldn't surprise me to find out there are several. Just flip through your field guides and take a look at the pictures. Then again, if we have learned anything from DNA studies of mushrooms we have learned that the physical features of mushrooms (for example the color of the cap) are not necessarily indicative of meaningful genetic difference--so it may be the case that there is only one species involved.

At any rate, many sources treat Lyophyllum decastes as a constellation of (potential) species, and that is what I will do here. The salient features of the group, then, are:

• Growth in dense (and often huge) clusters on the ground, usually in areas where the ground has been disturbed (roadbeds, paths, landscaping areas, etc.) but sometimes in woods.
• A pure white spore print.
• Pleasant or mild taste.
• Absence of a partial veil or universal veil.
• A medium-sized cap that is whitish, brownish, yellowish brown, or grayish brown.
• Gills that are white but may yellow somewhat in age.
• Spores that are inamyloid, unornamented, and more or less round.
• Gill faces and edges that lack cystidia.
• Basidia that display granular contents when treated with acetocarmine.

If you have matched all of these characters, you can be pretty sure you have found Lyophyllum decastes. Yes, that's ridiculous--but my point is that Lyophyllum decastes, while edible and often called the "Fried Chicken Mushroom" in field guides, should not be eaten by beginners. The poisonous Clitocybe dilatata, for example, matches all of the features above except for having a "somewhat sour" taste, spores that are broadly elliptical, and basidia that do not react to acetocarmine. Thus, if you are not already familiar with Lyophyllum decastes, have not used a microscope, and have cooked it up for dinner, you have hung your well being by a thread composed of the difference between "pleasant or mild" and "somewhat sour."

Description:

Ecology: Saprobic; usually growing in dense clusters in disturbed soil (roadbeds, paths, landscaping areas, and so on), or occasionally growing alone or scattered (and sometimes occurring in woods); summer and fall (fall through spring on the West Coast); widely distributed in North America.

Cap: 3-12 cm; convex, becoming broadly convex or flat; moist (but not slimy) when fresh; smooth; grayish brown to yellowish brown or brown (usually darker when young; nearly white in Lyophyllum connatum and dark brown in Lyophyllum loricatum); often somewhat streaked in appearance; the margin inrolled at first, later even, lobed, or upturned.

Gills: Attachment variable (attached to the stem, sometimes by a notch, or beginning to run down it); close; white, sometimes yellowing somewhat with age.

Stem: 5-10 cm long; up to 2 cm thick; smooth; more or less equal; dry; whitish, sometimes becoming brownish toward the base.

Flesh: White; firm; not changing on exposure.

Odor and Taste:Taste pleasant or mild; odor not distinctive or somewhat fragrant.

Spore Print: Pure white.

Microscopic Features: Spores 4-6 µ; round or nearly so; smooth; inamyloid. Cystidia absent. Basidia with siderophilous granules when mounted in acetocarmine.

REFERENCES: (Fries, 1818) Singer, 1951. (Fries, 1821; Saccardo, 1887; Kauffman, 1918; Smith, 1975; Smith, Smith & Weber, 1979; Arora, 1986; Phillips, 1991/2005; Lincoff, 1992; Barron, 1999; Roody, 2003; McNeil, 2006; Miller & Miller, 2006; Kuo, 2007.) Herb. Kuo 09110406, 01130516, 09110514, 05140601, 11110701 (WW).

Clitocybe multiceps is a former name.

Lyophyllum loricatum has a cap that is blackish brown when young, a somewhat mealy taste, and slightly larger (6-7 µ) spores. Lyophyllum connatum is a white, European species reported from Colorado by Roger Phillips; it has elliptical spores (6-7 x 3.5-4 µ).

Further Online Information:

Lyophyllum decastes at MykoWeb
Lyophyllum decastes at Fungi of Poland

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Cite this page as:

Kuo, M. (2005, January). Lyophyllum decastes. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/lyophyllum_decastes.html