Kuehneromyces vernalis

Pileus
Cap 1.0-3.5 cm broad, convex, becoming plano-convex to plane, the disc slightly depressed or umbonate; margin at first incurved, appendiculate, decurved at maturity, even to wavy, inconspicuously striate when moist; surface glabrous, sometimes lubricous in youth, dull tan-brown, hygrophanous, fading from the disc, becoming buff-brown, in older specimens cream to white; context thin, approximately 1.0 mm thick, buff-brown, unchanging when injured; odor indistinct; taste mild.

Lamellae
Gills adnexed to shallowly notched, crowded, dingy pale-tan, in age dull, medium-brown; lamellulae up to 4-seried.

Stipe
Stipe 2.5-5.0 cm long, 2.0-3.5 mm thick, equal to narrowed at the apex, oval in cross-section, sometimes longitudinally grooved, hollow in age, often with a basal bend; surface of apex pruinose, pale-tan, lower portion glabrous to sparsely fibrillose, dingy vinaceous-brown, in old material the stipe almost entirely dark, vinaceous-brown; white tomentum at base proliferating into the substrate as rhizomorphs; partial veil fibrillose-membranous, pallid, evanescent, leaving fragments on the young cap and a thin fibrillose zone high on the stipe, the fibrils soon colored by mahogany-brown by maturing spores.

Spores
Spores 5.5-7.0 x 3.5-4.0 µm, elliptical, smooth, moderately thick-walled, flattened apically with a well-developed germ pore, hilar appendage not distinct; spores medium-brown in deposit.

Habitat
Gregarious to clustered on conifer logs, occasional in sawdust piles; found in montane areas; fruiting in late spring; common after wet winters.

Edibility
Unknown. A related fall-fruiting species, Kuehneromyces mutabilis, is considered a good edible, but caution is advised due to similar, potentially deadly Galerina species.

Comments
Kuehneromyces vernalis is an exception to the rule that small brown mushrooms are inherently difficult to identify. Distinctive features include clustered fruitings on montane, conifer logs in late spring, a hygrophanous, sometimes striate cap that fades from medium-brown to tan or white, and a partial veil that leaves fragments on the young cap. Closely related Kuehneromyces mutabilis is a fall-fruiting species which differs in having a squamulose lower stipe.