Psathyrella mucrocystis A.H. Sm.

Diagnosis fuente: PERSOONIA - A MYCOLOGICAL JOURNAL - VOLUME 11 - PART 4 - 1982 Rijksherbarium, Leiden, The Nederlands
     MACROSCOPICAL CHARACTERS. —Pileus in earliest stages (10-15 mm) subglobose-subparaboloid, at maturity 30-70(-90) mm and spreading via conico-paraboloid with truncate umbo to finally plane with vague and obtuse umbo and marginal area still deflexed (with Romagnesi: tending to become revolute), sometimes even depressed, firm and fleshy, not striate or sometimes substriate at margin, conspicuously dark reddish brown (M. 2.5 YR 3/4; 5 YR 3/4), at margin itself very pale brown, sometimes rugulose around centre when moist; hygrophanous, soon drying via (reddish) brown (M. 5 YR 3/3, 3/4, 4/4) and dark brown (M. 7.5 YR 4/4) to warm ochre brown (M. 5 YR 4/6, 4/8, 5/6, 5/8) or almost orange-brown (M. 5 YR 5/8), without pink, not micaceous, rugulose (with Romagnesi: at centre when moist slightly granular sub lente). Veil strongly (going by our own two collections) to rather little (with Romagnesi) developed (see observations). Numerous white fibrils and small tufts of fibrils reaching up to 3/4 from margin, increasing in number towards margin, forming wicker-works of floccose, stellate squamules with, at maturity, distinctly pale ochre brown tips, appendiculate, on lower 2/3-1/2 of stipe forming a dense floccose lanose-fibrillose, sometimes squamulose coating with sometimes an annuliform zone. Veil in primordia and subprimordial stages covering entire stipe beneath margin of pileus with a thick, dense, lanose-squamose layer, inserting at margin of pileus, covering pileus right up to the top (with Romagnesi: veil distinct in subprimordial stage but slight and fugacious, white, only leaving traces on pileus, not on stipe). pale brown (M. 10 YR 6/4), then brown (M. 7.5 YR 5/4, 4/4) and at maturity reddish brown (M. 5 YR 5/4, 4/4), contrasting with the dark pileus and pale brown stipe, with white, later whitish fimbriate edge. Stipe 30-60 x 4-8 mm (Romagnesi: 40-90 x 6-13 mm), its length about equalling diameter of pileus, relatively thick, firm, cylindrical, sometimes attenuated near apex or at base or at both, upper 1/3 whitish, lower 2/3 pale sordid brown, darker at sometimes swollen base, very hollow, not rooting, distinctly pruinose at striate apex. Context of pileus in centre 3-4 mm thick, at first reddish brown (M. 5 YR 3/3, 3/4), later dark greyish brown (M. 7.5 YR 4/2), in stipe whitish to pale yellowish brown, lower down darker and brownish grey, along cavity pale brown. Striking sweet smell of anise (Smith: almond). Trama of ‘washed’ lamellae strong yellowish brown (M. 10 YR 5/6) from many anastomosing, brownish yellow (M. 10 YR 6/6) strands running [rom base to edge, darker and merging in basal1/3 of lamella, through the in itself pale brown (M. 10 YR 6/3) tissue: extreme edge minutely fimbriate and pale brown. Spore print dark brown with purplish hue.
     MICROSCOPICAL CHARACTERS.—Spores (6.3-)7.2-8.1 x 4.1-4.5 jam (mean values 7.1 -7.5 x 4.5; 4 collections), in profile adaxially flattened ellipsoid to subphascoliform?, in face view ellipsoid to slightly ovoid, in water, NH,OH®,, and KOH 5°, brownish yellow (+ M. 10 YR 6/6,7.5 YR6/6), not opaque, without germ pore or callus, with small hilar appendix. Basidia 22.5-27.5 x 6-7.5 um, subcylindrical, 4-spored. Pleurocystidia: 20-32.5 x 7.5-15 xm (Romagnesi: 25-x 59-013. 5 yum; Smith 28-37x 8-14 jum), very scarce to moderately numerous, clavate with at apex a narrow (1-2 ym), cylindrical, 1-4 yum long, thin-walled, colourless protuberance (mucronate); cell body usually distinctly but very pale brown in NH,OH 10°, (particularly larger cells. Marginal cells: spheropedunculate and clavate cells 15-25(-27.5) x 7.5-15(-17.5) jum, very numerous, some with slightly thickened wall and some larger ones distinctly pale brown in NH,OH 10°; intermixed with very few to a fair number of scattered, colourless, mucronate, pleurocystidioid cheilocystidia, 20-30 x 7.5-11 yum. Caulocystidia: versiform, spheropedunculate, and clavate cells fairly numerous, 15-35 x 7.5-20 yum, some distinctly pedicellate; very few ellipsoid, rather large (27.5-40x 10-15 xm), mucronate pleurocystidioid cells with up to 7.5 zm long mucro. Pigmentation of hymenophoral trama in NH, OH 10%, sub micr.: distinctly brownish yellow from membrana] pigment; scattered yellow hyphal septa; no encrustations. Pileipellis: a 2-4 cells deep layer of subglobose, thick-walled, pale brown cells, 15-35 jum diam. Clamps present on hyphae of stem.
Habirat.—Caespitose or solitary on stumps of coniferous or deciduous trees.