Panaeolus acuminatus

[ Basidiomycetes > Agaricales > Bolbitiaceae > Panaeolus . . . ]

by Michael Kuo

Panaeolus acuminatus grows in grass and manured areas across North America, and can be separated from similar species of Panaeolus by its very long and very thin stem; the absence of toothlike fragments on the cap's edge (see Panaeolus papilionaceus); and microscopic features (see below). Panaeolus foenisecii is very similar but has a stouter stem and, under the microscope, wrinkled spores.

Panaeolus acuminatus is too tiny and too difficult to identify to consider for the table. It is not psychoactive, according to Stamets (1978).

Description:

Ecology: Saprobic; growing alone or scattered in grass, manured areas, and on dung; spring, summer, and fall; widely distributed in North America.

Cap: 1-2 cm; fragile; at first sharply bell-shaped; becoming broadly conic, broadly bell-shaped, or convex; dry; smooth; dark brown, fading to grayish; changing color markedly as it dries out, with two-toned specimens commonly encountered; the margin finely lined, lacking partial veil fragments.

Gills: Attached to the stem, or pulling away from it with maturity; close or crowded; grayish when young, but soon developing black areas and acquiring a mottled appearance; often with whitish edges; eventually black overall.

Stem: 8-12 cm long; only 1-2 mm thick; equal; finely hairy; often brittle; pinkish to reddish brown, or colored more or less like the cap; darkening toward the base with maturity or on handling.

Flesh: Insubstantial.

Odor and Taste: Not distinctive.

Spore Print: Black or blackish.

Microscopic Features: Spores 11-16 x 8-11 µ; smooth; lemon-shaped; with a pore; dark reddish brown in KOH. Pleurocystidia absent. Cheilocystidia fusoid-ventricose to irregularly cylindric; to about 35 x 10 µ. Pileipellis cellular/hymeniform, with pileocystidia.

REFERENCES: (Schaeffer, 1774) Quélet, 1874. (Saccardo, 1887; Stamets, 1978; Smith, Smith & Weber, 1979; Ola'h, 1969; Weber & Smith, 1985; Gerhardt, 1996.) Herb. Kuo 10190702.

Pileipellis, pileocystidium, spores

Cite this page as:

Kuo, M. (2007, December). Panaeolus acuminatus. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/panaeolus_acuminatus.html

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