Rhodocybe nitellina
Mycologia 38: 687. 1946.
Common Name: none
Synonym: Collybia nitellina
Cap 1.0-4.0 cm broad, convex, expanding to nearly plane, occasionally centrally depressed or with a low umbo; margin incurved in youth, translucent striate, becoming decurved to raised in age; surface, glabrous, hygrophanous, dull reddish-brown to orange-brown, drying to pinkish-buff or pale-tawny; context 1.0-2.0 mm thick at disc, firm, cream-buff, gradually tinged like the cap when cut or injured; odor and taste farinaceous.
Gills adnexed to notched, close, relatively broad, up to 3.0 mm wide, at first cream-colored, darkening slightly with age; lamellulae in three to four series.
Stipe 2.0-4.0 cm long, 2.0-5.0 mm thick, stuffed, brittle, more or less equal, the base sometimes pointed; surface of apex pruinose, pallid to buff, elsewhere glabrous, colored like the cap; partial veil absent.
Spores 6.5-7.5 x 4.0-5.0 µm, elliptical to tear-shaped in face-view and warted; angular in end-view; hilar appendage conspicuous, inamyloid; spore print pinkish-buff.
Scattered to gregarious on humus and soil under conifers in montane regions in the spring; fall and winter along the coast in mixed hardwood-conifer woods; uncommon.
Unknown.
This seldom collected member of the Entolomataceae is recognized by a collybioid stature, orange-brown to reddish-brown cap (when moist), farinaceous odor, and pinkish spores. Macroscopically it resembles Gymnopus dryophilus, a common early season mushroom, found as the species epithet suggests, under oaks. The latter is similar in color and hygrophanous, but lacks a translucent-striate cap margin, farinaceous odor, and possesses white rather than pinkish spores. Other Rhodocybe species occasionally encountered include Rhodocybe nuciolens, larger than R. nitellina with a pinkish-brown, non-striate cap, lacking a farinaceous odor, known primarily from coastal woodlands, and Rhodocybe caelata, a small greyish to greyish-brown species with a matted-tomentose, often depressed cap. Several collections of this nondescript mushroom have been made along the coast north of San Francisco and in the Sierra Nevada.