What You Should Know
Galerina sphagnorum is fond of sphagnum, so it is found primarily in bogs and swamps. It develops a proportionally long stem to raise its small caps high enough over the sphagnum to release spores that will be caught by air currents. G. sphagnorum has pale, virtually smooth spores, no pleurocystidia, and lageniform cheilocystidia that do not feature dramatically swollen tips.
G. sphagnorum closely resembles G. sphagnicola, a species also found growing in Sphagnum carpets. The only reliable way to distinguish the two is by microscopic examination of the basidiospores in 5% KOH. Those of G. sphagnicola are calyptrate and often have "ears" caused by a loosening of the outer basidiospore wall. There is no easy remedy for the similarity of the two names, which may also confuse.
Galerina sphagnorum Mushroom Identification
Saprobic; growing gregariously in sphagnum in marshes, bogs, and so on; summer and fall; northern and montane North America.
10–25 mm; conic at first, becoming broadly conic to convex with a sharp central bump; dry; bald; pale yellow to golden brownish; fading markedly as it dries out, creating a two-toned appearance; the margin lined, adorned with whitish veil fibrils when very young, but soon becoming naked.
Broadly or narrowly attached to the stem; close; short-gills frequent; whitish to yellowish at first, becoming brownish to rusty brown as the spores mature; not bruising; in very young buttons covered by a whitish partial veil.
50–75 mm long; 1–2 mm thick; more or less equal; dry; bald or with a few tiny fibrils; whitish to yellowish; basal mycelium white.
Insubstantial; brownish; unchanging when sliced.
Spores 8–10.5 x 5–6 µm; subamygdaliform; practically smooth; yellowish to brownish in KOH; dextrinoid. Basidia 4-sterigmate. Pleurocystidia absent. Cheilocystidia 35–50 x 7.5–10 µm; cylindric to narrowly lageniform, with a long neck and a rounded, subclavate, or subcapitate apex; smooth; thin-walled; hyaline in KOH. Pileipellis a cutis. Clamp connections present.
Photo 1 - Author: ninacourlee (Attribution 4.0 International)
Photo 2 - Author: https://www.inaturalist.org/observations/83961871 (Attribution 4.0 International)
Photo 3 - Author: https://www.inaturalist.org/observations/83961871 (Attribution 4.0 International)