Collybiopsis quercophila
Mycotaxon 136(2): 344. 2021.
Common Name: none
Synonyms: Marasmiellus quercophilus (Pouzar) J.S. Oliveira; Gymnopus quercophilus (Pouzar) Antonin & Noordel.; Marasmius quercophilus Pouzar; Setulipes quercophilus (Pouzar) Antonin
Cap 2-5 mm broad, convex, broadly so to plane in age, occasionally with the disc depressed; margin decurved, sometimes becoming plane, often sulcate; surface minutely pruinose (use hand lens), striate wrinkled to two-thirds the distance from the margin to the disc; color light-brown at the disc, pallid to cream-buff at the margin; context very thin, pallid; odor mild, taste: untried.
Gills adnexed, subdistant, moderately broad, whitish, lamellulae 1-2 seried.
Stipe 1-2.5 cm long, less than 1 mm thick, round, hair-like, equal, sometimes flexuous; surface at apex pallid to pale vinaceous-brown, sparsely pruinose, elsewhere glabrous, reddish-brown to dark-brown, instititious on leafy substrate, scattered rhizomorphs near base.
Spores 7.5-9.0 x 3-4.5 µm, ellipsoid to almond-shaped, smooth, nonamyloid, hyaline in KOH; spore print not seen.
Solitary to gregarious on rotting hardwood leaves, notably species of oak (Quercus) and tanbark oak, (Lithocarpus densiflora); fruiting shortly after the fall rains.
Unknown; too small to have culinary value.
Collybiopsis quercophila fruits on oak and tanbark leaves. Often up to a dozen fruiting bodies of this Lilliputan species may occupy the same leaf. It's distinguishing macroscopic characters are a pale, striate-wrinkled, minutely pruinose cap with a brownish disc, distant gills, a mostly dark-brown polished, hair-like stipe, and a lack of distinctive odor. Like many Marasmius-like species, it is capable of rehydrating to its original size and shape after drying.
Gymnopus quercophilus was transfered to the genus Marasmiellus by J.S. Oliveira in 2019 based on molecular data (see Oliveira et al. Mycological Research, 18-5) and then in 2021 to the genus Collybiopsis based on nomencatural priority (see Petersen & Hughes).
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Desjardin, Dennis E. (1987). The Agaricales (Gilled Fungi) of California. 7. Tricholomataceae I. Marasmioid Fungi. Mad River Press: Eureka, CA. 100 p.
Desjardin, Dennis E. (1987). New and Noteworthy Marasmioid Fungi from California. Mycologia 79: 123-134.
Desjardin, D.E., Wood, M.G. & Stevens, F.A. (2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
Noordeloos, M.E. & Antonín, V. (2008). Contribution to a monograph of marasmioid and collybioid fungi in Europe. Czech Mycol. 60(1): 21-27.
Oliveira, J.J.S., Vargas-Isla, R., Cabral, T.S., Rodrigues, D.P. & Ishikawa, N.K. (2019). Progress on the phylogeny of the Omphalotaceae: Gymnopus s. str., Marasmiellus s. str., Paragymnopus gen. nov. and Pusillomyces gen. nov. Mycological Progress 18(5): 713-739.
Petersen, R.H. & Hughes, K.W. (2021). Collybiopsis and its type species, Co. ramealis. Mycotaxon 136(2): 263-349. (PDF)
Pouzar, Z. (1982). Marasmius quercophilus, a new species, common on oak leaves. Česká Mykologie 36(1): 1-6.
Siegel, N. & Schwarz, C. (2016). Mushrooms of the Redwood Coast. Ten Speed Press: Berkeley, CA. 601 p.