Summary:
Features include 1) relatively large size, 2) gray color evident in the cap which is silky from scattered appressed fibrils and has at first hanging veil remnants, 3) adnate, narrow gills that are pallid becoming dark vinaceous brown with white crenulate edges, 4) a whitish silky stem with scattered fibrils, 5) growth in swampy areas under brush or on decayed aspen wood, and 6) microscopic characters. The description is derived from Smith(5). Orstadius(1) proposed the new combination Coprinopsis uliginicola (McKnight & A.H. Sm.) Orstadius & E. Larss. based on molecular study where the type of species was nested within Coprinopsis.

Gills:
narrowly adnate, crowded to close, narrow, 0.5-0.6cm broad, thin; pallid at first, finally dark vinaceous-brown, edges white; edges crenulate

Stem:
8-12cm x 1.2-1.5cm, equal, hollow, rigid, brittle; white or whitish; silky beneath scattered fibrils left by veil, becoming longitudinally cracked-grooved when old, white-mycelioid at base, lower part discoloring when handled

Veil:
universal veil rudimentary leaving scattered fibrils near margin and on stem, partial veil thin submembranous, at first leaving remnants hanging from cap edge

Odor:
not distinctive

Taste:
not distinctive

Microscopic spores:
spores 10-12(15) x 5-6 microns, elliptic to oblong in face view, more or less bean-shaped in side view, smooth, apical pore rather inconspicuous, in KOH sordid cinnamon to pale cocoa but soon with dark chocolate cast, in Melzer''s reagent tawny, wall about 0.3 microns thick; basidia 4-spored, 28-33 x 10-12 microns, clavate, colorless in KOH; pleurocystidia not differentiated, cheilocystidia abundant, of two types, the first 45-70 x 10-16 microns, elongate-utriform to cylindric, wall colorless, smooth and thin, content not distinctive, the second 10-16 x 8-12 microns, vesiculose to clavate, colorless and thin-walled

Spore deposit:
[presumably close to dark vinaceous-brown]

Notes:
Collections were examined from ID, NM, UT, and WY, (Smith). It has been reported from WA by Andrew Parker, pers. comm. There are collections from BC at the University of British Columbia.

EDIBILITY

Synonyms and Alternate Names:
Psathyrella uliginicola McKnight & A.H. Sm.