Closed pileus up to 15 x 12 mm, usually ochre-brown (Mu. 7.5 YR 4/6, 10 YR 3-4/3, 4/4, 4-5/6, K. & W. 6E5, 5D7) at centre, paler (Mu. 10 YR 5/3-6, 6/4, 8/5, 2.5 Y 5/2, K. & W. 5D6, 5C/D3) towards margin, up to c. 40 mm in diam. when expanded, only rarely entirely flattened. Veil present, visible at small, whitish, radially fibrillose flocks. Lamellae narrowly adnate, white to blackish; L= 24-36, l= 1-3. Stipe 40-100 x 1-3 (-4) mm, white to greyish-white, pubescent, with slightly clavate, up to 5 mm wide base.
  Spores [160,8,8] 7.5-11.5 x 4.3-5.9 µm, av. L= 8.8-9.7, av. B= 4.8-5.5 µm, Q= 1.60-2.10, av. Q= 1.70-1.90, ovoid to ellipsoid, obconical at base, truncate; germ pore central, c. 1.8 µm wide. Basidia 14-38 x 7-8 µm, 4-spored. Pseudoparaphyses 3-5 per basidium. Cheilocystidia 30-50 (-75) x 10-18 µm, lageniform with 3.5-7 µm wide, tapering neck. Pleurocystidia absent. Pileocystidia slender, 50-200 (-250) x 13-24 µm, lageniform, with 4-10 µm wide, tapering neck. Sclerocystidia absent. Veil on pileus consisting of cylindrical or somewhat inflated hyphae, with terminal cells 2-15 µm wide (somewhat wider than in C. heterothrix). Clamp-connections present.

Habitat

  On naked soil or grassy places. Gregarious and fasciculate, usually in bundles of more than 10 specimens. Rather common.

Remarks

  Coprinus hiascens is easily recognizable by the tapering, long pileocystidia in combination with the spore-shape, which is more or less similar to that of C. disseminatus, but in that species the spores are slightly smaller and cylindrical veil elements are lacking from the pileus. Moreover, C. disseminatus has pileocystidia with a broad, cylindrical, not tapering neck and velar spherocysts on the pileus.
  The obconical base of the spores distinguishes this species from other species with cylindrical veil elements on the pileus, which have spores with rounded bases. So far the presence of cylindrical veil has never been mentioned for C. hiascens. The basidiocarps and their habit remind of C. disseminatus, but those of C. hiascens are in general distinctly larger and smaller in number.