Summary: {See also Hemimycena Table.} Salient characters are microscopic: bulbose-based pileocystidia with a tapered upper part and small spores, (Redhead(15)). Other features include small size, white color, a translucent-striate cap, short-decurrent gills, a curved, pruinose stem that is thread-like except for the slightly swollen base, and growth on wet conifer wood. The description is derived from Redhead(15).
Cap: 0.15-0.5cm across, convex; white; translucent, rugose [wrinkled] and often somewhat pleated-striate, edges slightly crenulate
Gills: short arcuate decurrent, subdistant, one tier of subgills; white
Stem: 0.2-1cm x 0.01-0.02cm, thread-like except for slightly swollen base, curved; white or faintly buffy at base; finely powdered overall, appearing insititious or with small basal pad of mycelium
Odor: not distinctive
Microscopic spores: spores 5.5-7 x 3.3-4.2 microns, elliptic, smooth, inamyloid, white in mass; basidia 4-spored, 17-20 x 6-6.2 microns, clavate, clamped; gill trama hyphae similar to the cap tramal hyphae; pileipellis hyphae repent, inflated or not, 5-10 microns in diameter, some with sparse diverticula, with thin to pronounced walls, bearing numerous cystidia, pileocystidia "narrowly tapered to an acute or subacute apex, usually with a prominently swollen base which is sometimes constricted before the tapered upper portion, some also forked or branched at the extreme apex or constricted where a cylindrical extension of the tapered portion is present, the walls pronounced or refractive but not thick", 25-40 microns long, base 6-12 microns wide; cap trama hyphae parallel, cells cigar-shaped, 10-30 microns in diameter, thin-walled, smooth, clamped, inamyloid; stem hyphae "parallel, 5-15 microns diam. internally, 5-11 microns diam., thin walled, diverticulate on the outer surfaces, clamped, nonamyloid, bearing scattered cystidia"; caulocystidia similar to pileocystidia but larger 43-57 x 5-11 microns
Spore deposit: [presumably white]
Notes: Hemimycena substellata has been found in BC.
EDIBILITY
Habitat and Range
Habitat
gregarious "on the undersides of water-soaked or wet, decorticated, soft-decayed conifer wood in debris jams along a flood stream course of a steep ravine in the Subalpine forest region"