Psathyrella maculata (C.S. Parker) A.H. Sm.

Diagnosis Fuente: PERSOONIA - Suplement - Vol. 2 - THE DUTCH, FRENCH AND BRITISH SPECIES OF PSATHYRELLA - 1985 E. KITS VAN WAVEREN - Rijksherbarium, Leiden, The Nederlands
     Cap in earliest stages (10-15 mm) conico-paraboloid with slightly incurved marginal area, white due to the initially white but soon brown veil; at maturity spreading to 20-40 (—60) mm, convex or plane with deflexed marginal area, sometimes with vague umbo, fleshy, ground colour sordid white or pale brownish (Mu. 10 YR 6/3), covered with very dark brown, fuliginous (Mu. 7.5 YR 3/2; 10 YR 3/2), almost blackish velar fibrils forming a dense, united, coarsely tomentose pelt at centre but towards margin adpressed, disjointed broad bundles of fibrils and scales, exposing between them the sordid white flesh, with at margin scales paler to even whitish and appendiculate, hygrophanous, drying out to pale brownish grey (Mu. 10 YR 6/2), scales and bundles of fibrils shrinking and becoming blackish. Gills 2~5 mm broad, subventricose to almost straight, slightly ascending, narrowly adnate or emarginate, crowded, pale brown (as in Inocybe, Mu. 7.5 YR 6/2—6/4) when cap viewed from below, on face sordid brown (Mu. 7.5 YR 5/2), weak chocolate or reddish brown (Mu. + 5 YR 3/3), with white, fimbriate edge. Stem 30—50 x 2.5—-5 mm, cylindrical, often flexuous, with white ground colour, at base not yellow but sometimes black, fistulose, strongly and towards base increasingly and coarsely fibrillose-scaly from brown fibrils below annuliform zone or distinct annulus, sharply delimiting white pruinose sulcate apex from lower + 2/3—3/4. Flesh of cap in centre 3—4 mm thick, dark greyish brown (Mu. 10 YR 4/2) but superficial layer whitish, of stem pale yellowish brown, outer layer white. Smell indistinctive. Trama of ‘washed’ gill strongly pigmented, brownish yellow (Mu. 10 YR 6/6). Spore print brownish purple.
     Spores 4.5—5.5 x 2.5—3.5 um (mean values 4.6—5.2 x 3—3.4 ym: 5 collections), in face view broadly ellipsoid to ellipsoid-ovoid, in profile ellipsoid, adaxially flattened, in water and NH,OH 10% pale brownish yellow (Mu. 10 YR 6/6, 7/6), in KOH 5% pale olive yellow (+ Mu. 2.5 Y 6/4), not opaque; germ pore very indistinct, practically absent; hilar appendix distinct. Basidia 14.5—22.5 x 5—6.5 um, subcylindrical to subclavate. Pleurocystidia 22.5—35 x 10-15 vm, (rostrum, 2—12.5 x 2—3.5 um, sometimes swollen up to 5 wm at apex, excluded), clavate, rostrate, numerous, thin-walled, colourless. Marginal cells: pleurocystidioid cheilocystidia 20-35(—45) x 7.5-15(-17.5) um, abundant and densely packed, sometimes a few cells without rostrum, intermixed with few spheropedunculate and clavate cells, 10-22.5 x 5—10 um; all cells thin-walled and colourless; rostra very thin-walled, not or scarcely staining in Congo Red. Hymenophoral trama in NH,OH 10% distinctly brownish yellow, without yellow hyphal septa or encrustations. Pileipellis a 3—4 cells deep layer of globose, subglobose, sometimes short ellipsoid, colourless cells, 15S—30 um diam., under a thick layer of long, from brownish yellow membranal pigment strongly pigmented velar hyphae, 8-20 pm thick.
HABITAT & DISTRIBUTION. —- Caespitose, subcaespitose or solitary on stumps of coniferous and deciduous trees. Sept.-Nov. Rare in the Netherlands. Reported from France and the British Isles. Oars cemnwe vv sateen

Fuente de la foto: https://www.discoverlife.org/mp/20p?see=I_MWS47957&res=640