Psathyrella pseudocasca (Romagn.) Romagn.

Diagnosis fuente: PERSOONIA - A MYCOLOGICAL JOURNAL - VOLUME 11 - PART 4 - 1982 Rijksherbarium, Leiden, The Nederlands
MACROSCOPICAL CHARACTERS.
Pileus 22-33 mm, fairly fleshy, at first globose or campanulate, then convex, finally spreading with a distinct umbo gradually developing at centre, with margin regular or a little wavy, magnificently very intense reddish ochre brown, towards margin becoming more and more brown, slightly and only in the end striate, when moist glossy and smooth, hygrophanous, young pilei drying out to warm ochreous with centre for a while remaining reddish. Veil: pileus clothed with a remarkably abundant white veil, consisting of numerous dispersed flocci, reaching almost apex of pileus, disappearing in the end, forming an appendiculate soft felty membrane along margin of pileus; very plumose on stipe. Lamellae +3.5 mm broad, fairly crowded, thin, |= 3, subventricose, adnate, not or scarcely uncinate, at first pale yellowish grey, then pale greyish brown and remaining so, with white, strongly pruinose edge. Stipe 40-5x 03- 5 mm, subcylindrical, rigid, fleshy, hollow, white, scarcely sordid yellow in final stages, strigose at base, vaguely grooved at apex. Context of pileus in centre 3-4 mm, when moist reddish, paler when dry. Hymenophoral trama of ‘washed’ lamellae pale yellowish brown (M. 10 YR 6/4) at base, getting paler towards edge. Spore print dark brown (sepia) with a trace of purple.
MICROSCOPICAL CHARACTERS
Spores 6.8-7.2 x 3.6-4.5 um (mean values 7.1 x4 ym: | collection), in face view ellipsoid, in profile adaxially flattened ellipsoid, not phaseoliform, in water and NH,OH 10% fairly pale yellowish brown to brown (M. 10 YR 5/4, slightly paler than M. 7.5 YR 5/4), in KOH 5°, yellowish brown (M. 10 YR 5/6), not opaque, with distinct germ pore (1-1.5 sem) and small hilar appendix. Basidia 17.5-20 x 7.5-9 jum, clavate, 4-spored. Pleurocystidia 32.5-47.5 x9 12.5 jum, abundant, fusiform, subelliptic, sublageniform with acute to subobtuse apex and short, fairly broad pedicel, thin-walled, colourless, upper 1/4-1/2 (rarely more) of cells usually covered with conspicuous slightly refractive in NH,OH 10°, very pale greyish green, structureless mucoid substance, staining very dark red and becoming minutely granular in neutral red, but not staining blue-green in NH,OH 10°, (this substance locally ‘dripping’ along sides of cells) causing the cells seemingly to have one or more inclusions. No crystals. Marginal cells: spheropedunculate and clavate cells small, 15-22.5 x 8-12.5 jum, abundant, intermixed with a moderate number of pleurocystidioid cheilocystidia 27.5 40 « 8-12.5 jum: all cells colourless; no crystals. Caulocystidia not found. Pigmentation of hymenophoral trama in NH,OH 10°, sub micr.: hyphae very pale yellowish brown; few yellow hyphal septa: no encrustations. Pileipellis a 2.3 cells deep layer of vesiculose cells, practically colourless. Clamps present on hyphae of stipe.
HÁBITAT & DISTRIBUTION. Around stumps of frondose tres.