Summary:
Also listed in Veined category. Marasmius epiphyllus is characterized by a small, white, convex, minutely wrinkled cap; rudimentary vein-like distant gills that are white or pale yellowish; and a thread-like pruinose stem that is whitish in the upper part and dull yellowish brown at the base.

Cap:
0.1-1cm across, convex when young, flat-convex or flat in age, rarely depressed; white or 'yellowish white' overall when young, disc becoming 'pale yellow' or 'yellowish orange' when old, margin white; minutely pruinose, dull, opaque, smooth or minutely rugulose [wrinkled], margin obscurely striate in age, (Desjardin), 0.1-0.7cm across, nearly pulvinate [cushion-shaped] at first, then convex to flat-convex or sometimes flat, rarely with a slight central depression; "white to yellowish white, becoming pale yellow to light orange yellow centrally" when old and on drying; dry, dull, opaque becoming translucent when old, minutely pruinose to minutely velvety, smooth but when old and on drying minutely rugulose, (Gilliam), 0.2-1.5cm across, white, (Hansen), 0.5-1cm across, flattened when old; milk-white then more or less dirty; somewhat wrinkled, (Moser)

Flesh:
thin; buff, (Desjardin), scarcely distinguishable; yellowish white to white, (Gilliam)

Gills:
frequently adnate, sometimes attached to an adnate partial collar, distant, few or rarely lacking altogether, narrow and vein-like, 1-4 tiers of subgills (vein-like), interveined; white or pale yellowish white, (Desjardin), "adnate or sometimes attached in pairs to a partial, adnate collar", straight, distant to remote, few (up to 13 reaching stem) or rarely lacking altogether, almost vein-like, usually less than 0.05 broad, but up to 0.1cm broad, thin or somewhat thick, equal or unequal, with 1-4 short vein-like subgills, usually interveined, occasionally forked; white to yellowish white, drying pale yellow; pruinose, (Gilliam), often reduced and vein-like or fold-like, often anastomosing and/or forked, (Hansen), almost decurrent, distant; whitish, (Moser)

Stem:
0.6-2cm x 0.02-0.1cm, equal, round in cross-section, insititious; ''yellowish white'' overall when young, top remaining so but base becoming ''yellowish brown'', ''reddish brown'' or ''dark brown''; shiny, translucent when young, opaque when old, pruinose, pruinae yellowish white or reddish brown, (Desjardin), (0.2)0.6-1.7(3.5)cm x 0.01-0.03cm, equal or enlarged slightly at top or base, central, round in cross-section, straight but curling on drying, delicate then bristle-like, insititious, hollow; yellowish white overall at first, remaining so on upper 0.2cm and becoming yellowish brown to deep brown in lower part, sometimes dark brown or blackish brown at base when old; dry, shining, translucent overall at first but soon opaque except at top, pruinose overall with short, yellowish white to reddish brown hairs; basal mycelium "usually absent, or rarely with an inconspicuous fringe of hairs around the point of emergence"; rhizomorphs lacking; sterile stems sometimes present, (Gilliam), 0.5-4cm x 0.02-0.06cm, red brown to black with short hairs, (Hansen), brownish with whitish top, pruinose, (Moser)

Odor:
not distinctive (Desjardin)

Taste:
not distinctive (Desjardin)

Microscopic spores:
spores 9.6-12.3(13.2) x 3.6-4.8(5.4) microns, elongate-elliptic; basidia 4-spored, 24-33 x 7.8-10.2 microns, clavate; pleurocystidia scattered, similar to cheilocystidia, cheilocystidia scattered, 33-48 x 6-10.8 microns, clavate, fusoid-ventricose, or ventricose-rostrate, projecting 10-27.6 microns, colorless, inamyloid, thin-walled, (Desjardin), spores (7.1)8.1-11.6(12.6) x 2.8-4.5 microns, pip-shaped or subcylindric, basidia 4-spored, 21-39 x 5.5-10 microns, clavate, basidioles subfusiform, (Gilliam), spores 8.5-9.5(11) x 3.5-5 microns, elliptic to dacryoid (tear-shaped); pleurocystidia and cheilocystidia 20-60 x 6-10 microns, lageniform, (Hansen), spores 8.5-10 x 3.5-4 microns (Moser)

Spore deposit:
white (Gilliam)

Notes:
Collections of Marasmius epiphyllus were examined from BC, AB, MB, NB, NS, ON, PQ, YT, AK, MI, NH, NY, UT, WY, Finland, Sweden, and United Kingdom, and the range is across boreal North America from the Yukon to Nova Scotia, south along the Rockies to AZ and in the Sierra Nevada, Greenland, northern Europe to North Africa and Israel, through to central and far eastern Russia, (Redhead(6)). It is also found in CA (Desjardin). There are collections from WA, MS, and WY at the University of Washington and a collection from OR at Oregon State University. It is also found in Europe including Switzerland (Breitenbach), and Britain/Ireland (Buczacki).

EDIBILITY

Synonyms and Alternate Names:
Marasmius subvenosus Peck
Tremella lutescens Pers.: Fr.