First person to use this name on MO: Nathan Wilson
Cap: 3-10 cm; convex, becoming broadly convex; dry; covered with small, erect, fibrillose, black scales over a whitish to grayish ground color; the scales 1-3 mm wide at the base; the margin hung with remnants of a whitish to grayish partial veil.
Pore Surface: Whitish, becoming gray; bruising reddish gray, then dark brown to black; pores circular to angular, 1-3 per mm; tubes to 2 cm deep.
Stem: 4-8 cm long; 0.5-2 cm thick; more or less equal; whitish to grayish and reticulate near the apex; dark gray to black and shaggy below; at first covered with a sheathing, grayish partial veil, but soon with merely an ephemeral ring or ring zone; solid; base covered with dense, gray mycelium.
Flesh: Whitish throughout, turning reddish when sliced, then slowly red to dark red and eventually nearly black.
Odor and Taste: Not distinctive.
Chemical Reactions: Ammonia negative to slightly bluish on cap; yellowish on flesh. KOH dark red on cap; orangish on flesh. Iron salts negative on cap; dark bluish on flesh.
Spore Print: Black.
Microscopic Features: Spores 9-12 × 8-12 µ (including ornamentation); globose to subglobose; with ornamentation of spines and occasional short ridges; not reticulate; brown in KOH. Pleurocystidia clavate to fusoid-ventricose; to about 60 × 25 µ; with brown contents in KOH. Pileipellis a trichoderm with cylindric to clavate terminal elements.