Leucocoprinus birnbaumii (Corda) Singer
Sydowia 15(1-6): 67. 1962.

Common Name: none

Synonyms: Lepiota lutea, Lepiota birnbaumii, Leucocoprinus luteus

• Pileus

  Cap 2.0-5.0 cm broad, obtuse-conic to bell-shaped, broadly conic in age, margin at first incurved, then decurved to plane, conspicuously striate; surface more or less smooth at the disc, elsewhere sqaumulose or matted tomentose; color bright yellow to fluorescent yellow, soon fading to dingy, pale yellow; flesh thin, soft, fragile, unchanging; odor: strongly of "mushrooms;" taste, mild.

• Lamellae

  Gills free, close, moderately broad, thin, fragile, pale yellowish, the edges slightly darker.

• Stipe

  Stipe 2.5-7.0 cm long, 2-6 mm thick, round, slender, hollow to stuffed at maturity, equal except for an often enlarged base; surface matted fibrillose, especially at the apex, obscurely so below, especially in age or after handling; color like the cap, soon fading to pale yellow; veil membranous, pubescent, forming a narrow, fragile, superior annulus.

• Spores

  Spores 7.5-11 x 6-7 microns, oval to broadly elliptical, smooth, thick-walled, dextrinoid, with an apical germ pore.

• Habitat

  Solitary, scattered to clustered on the soil of potted greenhouse plants; occasional outdoors in grass or well-decayed wood chips; fruiting year-round in greenhouses, restricted to late summer or early fall outdoors.

• Edibility

  Possibly poisonous, to be avoided.

• Comments

  This diminutive mushroom, typically found on the soil of potted indoor plants, is easily recognized by a bright-yellow (when fresh, it fades rapidly in the sun), finely-scaled, bell-shaped, striate cap, thin, collar-like annulus, and free, yellowish gills. A close relative is Leucoprinus cepaestipes which has a white, striate cap and fruits outdoors on well rotted wood chips or in grass under conifers.

• Other Descriptions and Photos
  • Ted Bessa: Leucocoprinus birnbaumii (CP)
  • Fred Stevens: Leucocoprinus birnbaumii (CP)
  • Nathan Wilson: Leucocoprinus birnbaumii (CP)
  • Michael Wood: Leucocoprinus birnbaumii (CP)
  • Michael Wood: Leucocoprinus birnbaumii (CP)
  • Michael Wood: Leucocoprinus birnbaumii (CP)
  • Agaricales of the Hawaiian Islands: Leucocoprinus birnbaumii (CP)
  • Page perso de JJ.Wuilbaut: Leucocoprinus birnbaumii (CP)
  • Arora (1986): p. 302 (D), plate 70 (CP) [Lepiota lutea]
  • Arora (1991): p. 91 (D& CP) [Leucocoprinus luteus]
  • Breitenbach & Kränzlin (vol. 4): sp. 246 (D, I, & CP)
  • Lincoff: p. 518 (D), plate 180 (CP) [Lepiota lutea]
  • Phillips: p. 34 (D), p. 35 (CP)
  • Smith & Weber: sp. 164 (D & CP) [Lepiota birnbaumii]
  
  

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