Tricholoma myomyces

Pileus
Cap 1.5-4.5 cm broad, convex, plano-convex to plano-depressed, the disc often slightly elevated; margin incurved in youth, wavy, with adhering pallid fibrils, eventually decurved to upturned in age; surface felty-tomentose becomingly squamulose, dark grey to blackish over a pallid background, the margin lighter; flesh thin, grey; odor mild; taste of cucumber.

Lamellae
Gills abruptly adnexed to sinuate, close, moderately broad, pale-grey, pallid in age.

Stipe
Stipe 1.5-5.0 cm tall, 5.0-8.0 mm thick, equal, solid at first, then developing a thin, hollow core at maturity; surface of apex with scattered scales, smooth to silky below, pallid when young, dingy, light-grey in age; partial veil fibrillose, evanescent, leaving remnants high on the stipe or on the young cap margin.

Spores
Spores 5.0-7.0 x 3.5-4.5 µm, elliptical in face-view, similar in profile, smooth, thin-walled, inamyloid; spore print white.

Habitat
Scattered to gregarious under conifers in coastal forests; common with Pseudotsuga menziesii (Douglas fir); fruiting from fall to mid-winter.

Edibility
Questionable. Though apparently edible and sometimes abundant, too little is known about this and related species to recommend it. Tricholoma pardinum, for example, which also has a grey, scaly cap, but is larger, is known to be toxic.

Comments
This diminutive member of the Tricholoma clan is recognized by a dark-grey to almost blackish, squamulose cap with contrasting pale margin, and sparse cortina-like veil. Traditionally it has been known as Tricholoma terreum in older field guides, but according to Shanks (1997), the latter, which lacks a veil, may not be present in California. Other small, grey Tricholomas include Tricholoma scalpturatum and Tricholoma moseri. Tricholoma scalpturatum has a lighter grey, less squamulose cap and strong farinaceous odor, while Tricholoma moseri is a montane, snowbank species with a mild odor, lacks a partial veil, and has larger spores.