Cap 2.0-5.5 cm broad, convex, becoming nearly plane, the disc sometimes slightly depressed; margin at first incurved, then decurved, occasionally wavy at maturity; surface dry, tomentose, dark brown at the disc, elsewhere the cuticle becoming fibrillose-squamulose, the scales more dispersed towards the margin, revealing a pallid context; cuticle staining pinkish-orange where injured, then becoming dark-brown; context white, soft, thin, up to 3 mm thick, discoloring irregularly pinkish-orange where cut; odor and taste mild.
Gills free, close, white, bruising pinkish-orange, then fading, edges of injured gills often eventually brown, lamellulae 1-3 seried; edges minutely ragged (use hand lens).
Stipe 4-10 cm long, 4-8 mm thick, round to grooved, slender, fragile, hollow to stuffed at maturity, more or less equal or slightly enlarged at the base; surface dry, white, fibrillose-striate above the veil, similarly colored below with scattered fibrils, staining pinkish-orange when bruised, eventually discoloring brown; veil membranous thin, white, forming a fragile, flaring, superior ring, the margin sometimes brownish in age, ring attached to the stipe via a short sleeve and bruising like the stipe.
Spores 6-7.5 x 3.5-4 µm, elliptical, smooth, weakly dextrinoid; spore print white.
Solitary to scattered under both hardwoods and conifers; fruiting from early to mid-winter.
Unknown. Some small Lepiotas are deadly poisonous!
Lepiota roseifolia is easily recognized by the pinkish-red bruising of all parts of the fruiting body. It is sometimes confused with Lepiota flammeatincta, but only the cap and stipe of this species redden, the gills remaining white. Lepiota roseifolia can often be found fruiting with other early season Lepiotas (s.l.), namely Leucoagaricus rubrotinctus, L. castaneidisca, and L. atrodisca.