Pileus 10-20 x 8-15 mm, first subglobose, broadly ellipsoid or ovoid, then hemispherical or obtusely conical to convex when expanding and then 25-40 mm wide, very deliquescent. In young stage white, soon greying from the margin, at centre becoming pale brown to ochre. Veil at first covering the whole pileus, felty, silky fibrillose, then splitting up in small, woolly-felty, white flocks (like in Amanita species), at the tips and in centre becoming brownish, ochre-brown. Lamellae, L = c. 50-60, very crowded, first white, then grey-brown, finally black. Stipe 40-80 x 2.5-3.5 mm, equal or slightly tapering to the apex, snow-white at submarginate bulbous base, upwards and at maturity more watery white or slightly brownish, minutely fibrous-floccose when fresh.
  Spores [160,6,3] 7.3-9.7 x (5.6-)6.9-9.3 µm, subglobose, globose, the shape of a maize-kernel or rounded quadrangular (some spores are elongate cylindrical-ovoid; the breadth, av. B, Q and av. Q are put in parentheses), truncate, red-brown (Mu. 2.5 YR 3/6 - 5 YR 4/6; K. & W. 8E8 - 8E6), with distinctly paler spot on the suprahilar plage, or with entirely pale plage, and with large, slightly eccentric to almost central, c. 3 µm wide germ pore; Q = 1.00-1.20(-1.40), av. Q = 1.05-1.10(-1.25); av. L = 7.6-8.7, av. B = (6.7-)7.2-8.2 µm. In some spores, two very small apiculus-like knobs occur on the sides. When the spores germinate, the spore wall tears open with jagged edges. Basidia 22-36 x 8.5-10 µm, 4-spored, surrounded by (4-)5-6 pseudoparaphyses. Pleurocystidia 80-200 x 25-60 µm, utriform, conical or fusiform and then rather acute at apex in most cases or utriform. Cheilocystidia similar to pleurocystidia but somewhat smaller in part. Elements of veil 2-8 µm wide, strongly diverticulate, excrescences up to 20 µm in length with very thick walls, up to 3 µm thick and pale yellowish; long, up to 350 µm and 2-4 µm wide, thick-walled, hair-like terminal elements grow out of thick-walled, veil-like hyphae. Clamp-connections present.

Habitat & distribution

  Solitary or a few together, on bare, gravelly-calcareous soil or in deciduous forests in mossy places; also found on burned places. Very rare. In Europe known from a few localities only. Not yet known from the Netherlands.

Remarks

  The paler spot on the plage or the entirely pale plage of the spores is a good character to distinguish C. spilosporus from C. gonophyllus. In addition the very thick-walled veil with elongate, hair-like terminal elements (up to 350 µm in length) and the (in great part) conical or fusiform cystidia are salient characters for this species.