Ecology: Saprobic; growing alone or scattered in grassy areas, usually in direct sunlight; summer and fall (and over winter in warmer climates); widely distributed in North America.
Cap: 10-35 mm across at maturity; ovoid at first, becoming convex or bell-shaped, then flat; bald; deeply grooved from the margin nearly to the center; yellowish to orangish brown when young, becoming gray in the grooves and finally overall; without veil remnants.
Gills: Free from the stem; close or nearly distant; whitish at first, becoming dark gray and eventually black.
Stem: 35-100 mm long; up to 2 mm thick; equal above a slightly swollen base; fragile; hollow; bald or very finely silky; white; without a ring.
Flesh: Insubstantial; whitish.
Odor and Taste: Not distinctive.
Spore Print: Black.
Microscopic Features: Spores 10-15 x 8-11 µ; angular-ovoid to limoniform or rarely subellipsoid; with a prominent, eccentric pore; smooth; dark reddish brown in KOH. Basidia 4-sterigmate. Pleurocystidia utriform or widely cylindric; to about 100 x 35 µ. Cheilocystidia utriform to widely fusoid-ventricose or rarely subsaccate; to about 90 x 30 µ. Pileipellis hymeniform; composed of sphaeropedunculate elements with tapered bases. Clamp connections present.
REFERENCES: (Curtis, 1787) Redhead, Vilgalys & Hopple, 2001. (Fries, 1821; Saccardo, 1887; Kauffman, 1918; Orton & Watling, 1979; Arora, 1986; Uljé & Bas, 1988; Lincoff, 1992; Metzler & Metzler, 1992; Breitenbach & Kränzlin, 1995; Baron, 1999; Uljé, 2001; Keirle et al., 2004; McNeil, 2006; Miller & Miller, 2006; Trudell & Ammirati, 2009.) Herb. Kuo 07060801, 07080801, 08020801, 08060802.
Parasola leiocephala is a virtually identical species characterized by smaller spores (measuring 8-12 x 7-10.5 µ) that are a little more angular, and habitat in bare soil or in shaded grassy areas.
Further Online Information:
Coprinus plicatilis at Uljé's Coprinus Site
Coprinus plicatilis at Roger's Mushrooms