Summary:
Features include 1) small size, 2) a dry cap that is whitish often with buff to fawn or cinnamon tints centrally, and also some rosy buff tones, 3) adnate gills that are whitish varying to faintly salmon or rosy buff, 4) a stem that is tough, pliant, narrow, often curved, buff to cinnamon in upper part, and darker lower down, 5) growth on senescent monocots or hardwood twigs, and 6) microscopic characters. There are problems with its placement in Marasmiellus and it is likely to end up in a different genus. The description is derived from Redhead(8) except where noted.

Cap:
0.2-1.3cm across, convex with incurved margins soon becoming flat to cyathiform, "margins sometimes becoming crisped or uneven"; "whitish often with buff to fawn or cinnamon tints centrally and also some rosy buff tones"; dry, becoming rugose [wrinkled], opaque, or vaguely translucent-striate

Flesh:
fleshy-tough, thin

Gills:
adnate, moderately spaced, subgills up to two tiers, moderately broad to narrow, "sometimes forked or with anastomoses"; "white varying to faintly salmon or rosy buff"

Stem:
0.3-2.2cm x 0.02-0.1cm, "equal or tapered below, often curved, tough and pliant, solid"; buff to cinnamon or ochreous in upper part, darkening in lower part to fulvous, sienna, or bay in older specimens; dry, powdered to minutely pubescent [downy] overall or becoming bald in lower part

Odor:
not distinctive

Taste:
not distinctive

Microscopic spores:
spores 8.0-9.2 x 3.8-4.1 microns, inequilaterally elliptic to rarely pip-shaped, with a prominent apiculus, smooth, inamyloid, colorless, thin-walled, sometimes multiguttulate [with several drops inside]; basidia 2-, 3-spored, 24-27 x 5.8-6.0 microns, narrowly clavate, with basal clamp connection, with elongated sterigmata; cheilocystidia "abundant, forming a sterile to nearly sterile margin", colorless, thin-walled, "with a short or long cylindrical pedicel and an obtusely coralloid apex", 26-40 x 11-12 x 3-4.5 microns; gill trama with hyphae similar to cap trama but tending to be subparallel towards gill extremes, subhymenial hyphae more densely interwoven; pileipellis "of repent, interwoven, filamentous hyphae with recurved to ascending hyphal ends" varying from relatively undifferentiated to coralloid cystidia-like forms, colorless, thin-walled, smooth, 4.5-10 microns wide, intergrading with trama hyphae; trama hyphae 4.5-10 microns wide, interwoven, colorless to faintly brownish, smooth to finely encrusted, inamyloid

Spore deposit:
white

Notes:
It has been found at least in BC, ON, NY, Czechoslovakia, Germany, and the United Kingdom, (Redhead). It has also been found in MA, NC, PA, SC, and TN, (Desjardin).

EDIBILITY

Synonyms and Alternate Names:
Marasmius vaillantii (Pers. ex Fr.) Fr.