Naematoloma aurantiaca: Hypholoma aurantiaca
Cap 2.5-6.0 cm broad, convex, becoming broadly convex, obtusely umbonate, margin with veil fragments disappearing in age; surface subviscid when moist, otherwise dry, smooth, reddish-brown to orange-brown; flesh thin, pale colored with pinkish tones below the cuticle; odor and taste mild.
Gills close, adnate to notched, at first pale greyish-brown, then olive-brown, finally brownish-purple at maturity, edges lighter than the faces.
Stipe 4-6 cm tall, 0.5-1.0 cm thick, equal to slightly enlarged at the base, the latter with conspicuous pallid to pale yellow mycelium; veil membranous, thin, leaving a fragile, evanescent, medial ring; surface pallid often developing orange-brown stains in age, smooth above ring, finely scaled below, the scales typically weathering away in age.
Spores 10-13 x 6-8 µm, elliptical, smooth. Spore print purple brown.
Solitary, gregarious to clustered on wood chips, occasionally in grass; from early fall to late winter, but fruiting sporadically any month of the year when moisture is available.
Leratiomyces ceres is an attractive small reddish-brown mushroom common in Bay Area parks but rare in natural woodlands. Besides its brightly colored cap, other identifying characteristics include an appendiculate cap margin when young, a purple brown spore print (often seen on overlapping caps) and its preference for woody debris, particularly wood chips.