Pileus up to 10 x 6 mm when still closed, up to c. 15 mm when expanded, first ellipsoid, cylindric-ellipsoid, grey-brown at centre beneath the whitish to silvery grey veil, paler towards margin, expanding to conical, then to convex or applanate, finally plano-concave with revolute margin. Veil whitish to pale (silvery) grey, radially splitting up into hairy to fibrillose, often pointed and appressed or - especially at centre - recurved flocks, the tips becoming brown on drying. Lamellae, L = c. 35, l = 1-5, free, narrow, rather crowded, first white, soon greyish brown to blackish. Stipe 20-50 x 0.5-1.5 mm, whitish, somewhat tapering towards apex, up to 2 mm wide at clavate base, hollow, minutely hairy flocculose, more dense at lower part, becoming glabrous with age; base clavate and often somewhat rooting.
  Spores [40,2,2] 13.3-15.2 x 7.6-8.5 µm; Q = 1.65-1.90, av. Q = 1.75-1.80; av. L = 14.2-14.6, av. B = 7.8-8.0 µm, cylindric-ellipsoid, with rounded base and apex, very dark red-brown to almost black, and central, c. 1.5-1.8 µm wide germ pore. Basidia 20-36 x 9-11.5 µm, 4-spored, surrounded by 4-6 pseudoparaphyses. Pleurocystidia 50-100 x 20-45 µm, ellipsoid to oblong, utriform or subcylindric. Cheilocystidia 35-80 x 15-40 µm, (sub)globose, ellipsoid to oblong or (sub)utriform. Pileipellis a cutis, made up of cylindrical or fusiform, more or less parallel, repent hyphae, up to 150 long and 3-30 µm wide. Veil made up of elongate, sausage-like elements, 30-250 x 8-25(-30) µm, often inflated, usually constricted at septa; terminal elements cylindric to almost globose. Clamp-connections present.

Habitat & distribution

  Growing solitary in groups or subfasciculate on heaps of mixed dung or on pure dung. Rather rare but wide-spread in Europe.

Remarks

  Coprinus radiatus can be recognized by the rather narrowly, cylindrical-ellipsoid spores with a length of 13-15 µm and the habitat on dung.