Coprinus atramentarius (Bull.: Fr.) Fries
Epicr. Syst. Myc. 243. 1838.

Common Name: Inky Cap

Synonym: Coprinopsis atramentaria (Bull.: Fr.) Redhead, Vilgalys & Moncalvo

• Pileus

  Cap 3-8 cm broad, oval, becoming conic, finally campanulate in age; grey-brown, dry, with innate silky fibrils; disc darker, usually with small flattened scales; margin striate to corrugated, deliquescing towards the center; flesh thin, pallid.

• Lamellae

  Gills crowded, free, white, becoming pinkish-grey, blackening in age.

• Stipe

  Stipe 6-15 cm long, 1-2 cm thick, white above, greyish-brown below the ring, dry, hollow, equal to sometimes enlarged at the base; veil fibrillose, forming an evanescent, basal annulus.

• Spores

  Spores 7-11 x 4-6 µm, elliptical, smooth, with an apical germ pore. Spore print black.

• Habitat

  Solitary to clustered, in grass, often near rotting wood; fruiting from fall to spring, although specimens can be collected any month of the year that moisture is available.

• Edibility

  Edible, but not recommended unless alcoholic beverages are avoided for several days before and after ingestion. It contains a compound, coprine, that can cause nausea, facial flushing, and an accelerated heart beat when ingested with alcohol.

• Comments

  Coprinus atramentarius is recognized by its smooth to silky, greyish-brown caps, clustered habit, and deliquescing gills. It prefers disturbed habitats and thus is at home in the urban environment where it inhabits dirt parking lots, gardens, and grassy areas. Like its cousin, Coprinus micaceus, it often fruits near buried wood. Coprinus atramentarius can be easily distinguished from Coprinus comatus which has a columnar-shaped, scaly cap, and from C. micaceus which a yellow-brown mica-flecked cap and is a smaller mushroom.

• Other Descriptions and Photos
  • Tom Duffy: Coprinus atramentarius (CP)
  • Michael Wood: Coprinus atramentarius (CP)
  • Cercle de Mycologie de Mons: Coprinus atramentarius (D & CP)
  • Informationszentrale gegen Vergiftungen der Universiteat Bonn: Coprinus atramentarius (D & CP)
  • The Bad and the Ugly: Coprinus atramentarius (D & CP)
  • Eileen's Mushroom Mania: Coprinus atramentarius (CP)
  • Eileen's Mushroom Mania: Coprinus atramentarius (CP)
  • George Barron's Fungi of Canada (East): Coprinus atramentarius (D & CP)
  • Pilze, Pilze, Pilze: Coprinus atramentarius (CP)
  • Coprinus Site: Coprinus atramentarius (D & CP)
  • Ammirati et al.: p. 135 (D), fig. 51 (I), fig. 53 (CP)
  • Arora (1986): p. 345 (D & P)
  • Arora (1991): p. 131 (D & CP)
  • Benjamin: chapter 15 (Toxicity Info)
  • Breitenbach & Kränzlin (vol. 4): sp. 265 (D, I, & CP)
  • Jordan: p. 228 (D & CP)
  • Lincoff: p. 596 (D), plate 19 (CP)
  • Miller: sp. 189 (D & CP)
  • Phillips: p. 204 (D), p. 205 (CP)
  • Smith: sp. 218 (D & CP)
  • Smith & Weber: sp. 179 (D & CP)

  (D=Description; I=Illustration; P=Photo; CP=Color Photo)