Bolbitius vitellinus (Pers.: Fries) Fries
Epicr. Syst. Myc. 254. 1838.

Photo: Young sporocarp on the left shows the typical 'egg yolk yellow' color.

Common Name: none

• Pileus

  Cap 2-6 cm broad, conic, becoming broadly convex with age; surface smooth, viscid, yellow to bright yellow when fresh, fading to whitish or greyish; margin striate; flesh thin, very fragile.

• Lamellae

  Gills adnate to adnexed, close, sometimes free, yellowish, to yellowish-brown at maturity.

• Stipe

  Stipe 6-11 cm long, 2-5 mm thick, equal to slightly enlarged at base, hollow, fragile, pale yellow, partial veil absent.

• Spores

  Spores 10-14 x 6-9 µm, elliptical, smooth, with a germ pore. Spore print rusty brown.

• Habitat

  Scattered on grass and dung. Fruits throughout the year whenever moisture is available.

• Edibility

  Edible, but too small and fragile to be of any interest.

• Comments

  Bolbitius vitellinus is a small, yellow, attractive mushroom that is easily recognized by its viscid, striate cap, yellow brown gills, rust-brown spores, lack of a ring, and habit of growing either on dung or grass. Like many small Coprinus (s.l.) species, fruitings are ephemeral, mushrooms opening in the morning, then shriveling by the end of the day. Occasionally, unusually robust specimens are found which may persist for several days. Leucocoprinus birnbaumii, a tropical species which in the Bay Area occurs mostly in greenhouses, is similar in size and cap color but the cap is not viscid, the gills are free, there is a ring, and the spores are white.

• References

  Bougher, N.L. & Syme, K. (1998). Fungi of Southern Australia. University of Western Australia Press: Nedlands, Australia. 391 p.
  Henderson, D.M., Orton, P.D. & Watling, R. (1969). British Fungus Flora: Agarics and Boleti: Introduction. HMSO: Edinburgh, Scotland. 58 p.
  Noordeloos, M.E., Kuyper, T.W. & Vellinga, E.C. (2005). Flora Agaricina Neerlandica—Critical monographs on the families of agarics and boleti occurring in the Netherlands. Volume 6. Coprinaceae & Bolbitiaceae. Taylor & Francis: Boca Raton, FL. 227 p.
  Smith, A.H. (1949). Mushrooms in their Natural Habitats. Sawyer's Inc: Portland, OR. 626 p.
  

• Other Descriptions and Photos
• Terry Goyan: Bolbitius vitellinus (CP)
• Taylor F. Lockwood: Bolbitius vitellinus (CP)
• Taylor F. Lockwood: Bolbitius vitellinus (CP) — a mature sporocarp showing striate margin
• Mark Steinmetz: Bolbitius vitellinus (CP)
• Mark Steinmetz: Bolbitius vitellinus (CP)
• Fred Stevens: Bolbitius vitellinus (CP)
• Fred Stevens: Bolbitius vitellinus (CP)
• Fred Stevens: Bolbitius vitellinus (CP)
• Boleslaw Kuznik -- Hunting for Mushrooms: Bolbitius vitellinus (CP)
• Il Mondo dei Funghi: Bolbitius vitellinus (D & CP)
• Pilze, Pilze, Pilze: Bolbitius vitellinus (CP)
• National Botanic Garden of Belgium: Bolbitius vitellinus (CP)
• Mushroom Observer: Bolbitius vitellinus (CP)
• Arora (1986): p. 474 (D & P)
• Breitenbach & Kränzlin (vol. 4): sp. 372 (D, I, & CP)
• Jordan: p. 250 (D & CP)
• Lincoff: p. 559 (D), plate 51 (CP)
• Miller: sp. 222 (D & CP)



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