Summary:
Features include tan to rusty-yellow, striate cap that may have fine shiny particles, pallid gills that soon become gray or brownish, then black, slender white stem, mild odor, gregarious growth on wood, and dark brown to black spore deposit. Coprinellus micaceus was in Section Micacei of Coprinus sensu lato. Note that other species in this section probably occur in the Pacific Northwest but have not been well studied. The description is derived from Arora(1) except where noted. C. micaceus is common in the Pacific Northwest and elsewhere in North America.

Cap:
1.5-5cm across when expanded, 2-4cm high when young, at first ovoid, soon bell-shaped, then expanding to convex; tan to yellow-brown to ocher buff, fulvous, or cinnamon brown (margin often paler) becoming grayer when old, especially toward margin; surface "sprinkled at first with minute glistening whitish particles (universal veil remnants)" that often disappear when old, striate at least halfway to center, "margin usually tattered or split at maturity", (Arora), glistening particles disappear easily in rain (Trudell)

Flesh:
thin, soft; pallid or white

Gills:
"crowded, adnate to adnexed or free"; "pallid soon becoming gray or brownish, finally black", deliquescing partly or completely

Stem:
3-8(12)cm x 0.2-0.6cm, "more or less equal, fragile, hollow"; white or discoloring buff; smooth

Veil:
sometimes slight basal ring presumably formed by universal veil as partial veil absent or rudimentary

Odor:
none (Phillips, Breitenbach)

Taste:
mild, insipid, (Breitenbach)

Microscopic spores:
spores 7-11 x 4-6 microns, elliptic, smooth, often flattened somewhat, (Arora), spores 6.5-9 x 3.9-5 x 4.9-6.3 microns, +/- miter-shaped in frontal view, almond-shaped to fusiform [spindle-shaped] in side view, smooth, dark brown, truncate from a central germ pore; basidia 4-spored, 22-31 x 6-10 microns, clavate, without basal clamp connection; pleurocystidia 70-100 x 50-70 microns, vesicular to elliptic, cheilocystidia 20-90 x 20-75 microns, vesicular to clavate; veil on the cap surface "of spherical cells, in part brownish, encrusted or thick-walled", only occasional septa with clamp connections, (Breitenbach)

Spore deposit:
dark brown to black (Arora), black (Breitenbach)

Notes:
There are collections from BC at Pacific Forestry Centre in Victoria. The University of Washington has collections from WA, OR, ID, AK, IA, and ON. Oregon State University has collections from OR and KS. Desjardin(6) illustrate from CA. Breitenbach(4) give the distribution as North America, Europe, Asia, North Africa, and Australia.

EDIBILITY

yes (Arora)

Synonyms and Alternate Names:
Coprinus micaceus (Bull.) Fr.