Gymnopus acervatus (Fries) Murrill
N. Amer. Flora 9: 362. 1916.

Common Name: none

Synonym: Collybia acervata Fries

• Pileus

  Cap 0.5-3.0 cm broad, convex when young with an incurved margin, at maturity broadly convex, the margin then decurved; surface glabrous, subviscid when fresh, dingy reddish-brown to vinaceous-brown, hygrophanous, fading when dry to buff-brown; context thin, 1-2 mm thick, colored like the cap, unchanging when cut; odor not distinctive; taste slightly bitter.

• Lamellae

  Gills narrowly attached, sometimes appearing free, close, relatively broad, cream-buff to pale vinaceous-buff; lamellulae up to two-seried.

• Stipe

  Stipe 4-10 cm long, 2-3 mm thick, straight, equal, round, hollow, cartilaginous; surface of apex pale vinaceous-brown, glabrous or with faint appressed fibrils, dull reddish-brown below, the base covered with pallid hairs; stipe base fused with those of other fruiting bodies; partial veil absent.

• Spores

  Spores 5.0-6.0 x 2-2.5 µm, smooth, narrowly tear-shaped, inamyloid, possibly slightly amyloid; spore print white.

• Habitat

  In dense clusters on rotting conifer stumps and logs; fruiting from after the fall rains to mid-winter; uncommon in the inner San Francisco Bay Area, but collected regularly along California's north coast and in the Sierra.

• Edibility

  Inedible, bitter.

• Comments

  Gymnopus acervatus is recognized by the dense clusters of small reddish-brown mushrooms that it produces on rotting conifer stumps and logs. In age the color fades, but it can still be recognized by the somewhat slippery, convex cap, persistently incurved margin, and two-toned stipe, pale at the apex, dull reddish-brown at the base. Look-alikes include clustered, lignicolous Mycenas such as M. haematopus, M. galericulata and M. maculata. These can be separated by their more conic to campanulate, striate-margined caps.

• References

  Antonín, V. & Noordeloos, M.E. (1997). A Monograph of Marasmius, Collybia and related general in Europe. IHW - Verlag: Eching, Germany. 256 p.
  Bas, C., Kyper, T.W., Noordeloos, M.E. & Vellinga, E.C. (1995). Flora Agaricina Neerlandica -- Critical monographs on the families of agarics and boleti occuring in the Netherlands. Volume 3. Tricholomataceae. A. A. Balkema: Rotterdam, Netherlands. 183 p.
  Halling, R.E. (1983). The Genus Collybia (Agaricales) in the Northeastern United States and Adjacent Canada. J. Cramer: Braunschweig, Germany. 148 p.
  Smith, A.H. (1949). Mushrooms in their Natural Habitats. Sawyer's Inc: Portland, OR. 626 p.
  

• Other Descriptions and Photos
  • Fred Stevens: Gymnopus acervatus (CP)
  • Nathan Wilson: Gymnopus acervatus (CP)
  • Michael Wood: Gymnopus acervatus (CP)
  • Michael Wood: Gymnopus acervatus (CP)
  • Michael Wood: Gymnopus acervatus (CP) -- the white around the caps is ice crystals!
  • A revision of Collybia s.l. in the northeastern United States and adjacent Canada: Gymnopus acervatus (D, I, & CP)
  • George Barron's Fungi of Canada (East): Gymnopus acervatus (D & CP)
  • Mushroom Observer: Gymnopus acervatus (CP)
  • Arora (1986): p. 215 (D), plate 49 (CP) [Collybia acervata]
  • Halling: p. 42 (D) fig. 26-28 (I) [Collybia acervata]
  • Lincoff: P. 753 (D), plate 23 (CP) [Collybia acervata]
  • Miller: sp. 138 (D & CP) [Collybia acervata]
  • Phillips: p. 60 (D & CP)
  • Smith & Weber: sp. 113 (D & CP) [Collybia acervata]
  
  

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