Macroscopic features

  Pileus 20-40 x 15-30 mm when still closed, first white, later grey; expanded pileus up to 50 mm. Veil splitting up in small patches. Lamellae very crowded, free, first white then grey to blackish. Stipe up to 200 x 5-10 mm, white, greyish white, first covered with minute white flocks from veil, soon smooth; base bulbous, woolly-hairy.

Macroscopic features

  Spores [20,1,1] 12.5-15.6 x 7.9-10.0 µm, ovoid or slightly amygdaliform, mainly rounded at apex, dark red-brown, with somewhat eccentric, 1.6-1.8 µm wide germ pore; Q = 1.45-1.70, av. Q = 1.55; av. L = 14.1, av. B = 9.1 µm. Elements of veil branched, weakly diverticulate with in part swollen cells, 40-200 x 4-8(-10) µm, inflated cells up to 15 µm. Clamp-connections present.

Habitat & distribution

  Habitat not noted. Very rare, only known from one locality in the Netherlands.

Remarks

  Only one specimen is present in the Rijksherbarium (L). This mature basidiocarp is in bad condition. Therefore no cystidia nor other important characters could be found in the material. Spore size of this basidiocarp, however, is clearly different from the closely related Coprinus stanglianus and C. picaceus. Therefore the description is included in this paper to draw attention to this taxon, in the hope that it will be collected again.