Summary:
Section Subincarnatae (Smith), Section Pterygenae (Maas Geesteranus); Mycena pterigena is distinguished by small size, pink color and habitat on decaying fern fronds. It is generally rare but can be found in abundance.

Cap:
0.1-0.25cm across, narrowly parabolic; at first coral to apricot or peach, soon whitish with coral tints centrally and on margins; translucent and somewhat plicate-striate [pleated-striate], margins entire, (Redhead), 0.2-0.5cm, obtusely conic with an appressed margin becoming broadly conic to convex; bright, often delicate rose, gradually fading to grayish vinaceous especially on the disc, rose tints often persisting along margin or margin whitish; bald, somewhat translucent-striate, (Smith)

Flesh:
thin, membranous; colored as cap, (Redhead), membranous but not fragile (Smith)

Gills:
ascending, broadly adnate, moderately spaced, 1 tier of subgills; whitish with coral-tinted margins, (Redhead), "ascending, broadly adnate, distant, narrow to broad"; pale rose becoming whitish, edges fading or remaining pale rose, (Smith)

Stem:
0.2-3.5cm x 0.01-0.02cm, thread-like, subinsititious, with a slightly swollen base and a minute nearly colorless appressed corona; faintly coral to whitish; bald except for a slight basal pubescence, (Redhead), 2-4cm, thread-like or up to 0.05cm thick, tough, flaccid, stem not readily separable from cap; colored as cap, becoming pale and transparent, finally grayish brown; bald, "attached to fern debris by a thin mat or by groups of radiating white hairs", (Smith)

Odor:
not distinctive (Redhead)

Taste:
indistinct (Buczacki)

Microscopic spores:
spores 7-9 x 3.5-5 microns, narrowly to broadly elliptic, smooth, strongly to weakly amyloid in the same mounts, colorless, thin-walled, bearing a conspicuous apiculus; basidia 4-spored, 23-28 x 8-8.5 microns, clavate, inamyloid; cheilocystidia abundant, forming a sterile edge, 19-24 x 11-13 microns, clavate to saccate, inamyloid, covered apically by short to long finger-like projections up to 10 microns long, (Redhead), spores 8-10(11) x 4-4.5 microns, narrowly elliptic to subcylindric [nearly cylindric], amyloid; basidia 4-spored; pleurocystidia "rare to scattered (sometimes apparently absent), similar to the cheilocystidia", cheilocystidia 20-32 x 9-14 microns, "broadly ellipsoid or clavate to subglobose", apex studded with short rod-like projections, contents colorless or pale pinkish, (Smith)

Spore deposit:
[presumably white]

Notes:
It has been found in WA, OR, NY, and MI, according to Smith for M. pterigena (Fr.) Quel. It has been recorded for BC, WA, OR, ID, also NL, ON, MI, NY, Sweden, and the USSR, (Redhead).

EDIBILITY