Coprinellus micaceus

Scientific name:  Coprinellus micaceus (Bull.) Vilgalys,
Hopple & Jacq. Johnson
Derivation of name:  Micaceus means "glistening" and
describes the shiny particles on the cap.
Synonyms: Coprinus micaceus (Bulliard:Fries) Fries
Common name(s):  Mica cap.
Phylum:   Basidiomycota
Order:   Agaricales
Family:   Psathyrellaceae
Occurrence on wood substrate:  Saprobic; densely clustered
around stumps, wood debris, at the base of standing dead or
dying trees or in grassy areas from buried wood; April through
October.  
Dimensions:  Caps 2-5 cm wide; stipes 2.5-8 cm tall and 2-5
mm thick.   
Cap:  Reddish-brown to tawny to ochre-brown, becoming
grayish particularly near the margin; surface covered by
glistening granules that are soon lost; cap radially lined almost
to the center.        
Gills: Attached to nearly free; white, becoming black and inky
with age but not entirely dissolving. 
Spore print: Black.
Stipe: White
Veil: Absent.
Edibility: Edible.
Comments: DNA studies (see Redhead, S. A., et al.
2001) radically revised the taxonomy of Coprinus. The
genus Coprinus was divided into several new genera
and the family Coprinaceae no longer exists.

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Figure 1. A clump of mica cap. Photo © Pam Kaminski.

Figure 2. Older specimens become grayish. The woody
debris these specimens are growing on is mostly obscured
by the fallen leaves. Photo © Gary Emberger.

Figure 3. This clump of mica caps was growing on a log in
a wood pile but the fallen leaves obscured the connection
of the mushrooms to the wood. Photo © Gary Emberger.

Figure 4. The clump of mica caps in Figure 2 with the
leaves removed. Not only is the substrate revealed
but also the elongation of the stems to position the caps
above the leaves. Photo © Gary Emberger.

Figure 5. The caps are conspicuously striate. Photo ©
William Roody.

Figure 6. The gills of the mature specimens on the left are
partially auto-digested into an inky fluid. Photo © Larry
Grand.

Figure 7. The glistening mica-like particles are visible on
these young specimens. Photo © David Work.

Figure 8. Mica-like granules on an older specimen.
Photo © Gary Emberger.

Figure 9. The mica-like granules on the cap surface are the
remnants of a universal veil. Photo © Gary Emberger.

Figure 10. The mica-like particles quickly fall away with
age or may be washed off by rain. They are often not very
evident on older specimens. Photo © Gary Emberger.