The North American Species of Pholiota
195. Pholiota subflavida (Murr.) comb. nov.
Gymnopilus subflavidus Murrill, 4: 252. 1912.
Flammula subflavida Murrill, Mycologia 4: 262. 1912.
Pileus 3-5 cm broad, thin, conic or convex to expanded, umbonate when young, melleous with fulvous center, becoming green-spotted when handled, slimy, glabrous, smooth, margin entire, strongly incurved.
Lamellae sinuate or adnate, citrinous to fulvous, medium broad, subdistant.
Stipe 4-7 cm long, 5-8 mm thick, equal, cremeous above, pale fulvous below, smooth, fibrillose. Veil slight, citrinous, membranous in young stages, soon breaking into fibrils and leaving no annulus.
Spores 5.5-7.5 (8.5) x 3.5-4.5 (5) µ, smooth, apical pore small but distinct; shape in face view elliptic to ovate, in profile obscurely inequilateral; color tawny in KOH under microscope, in Melzer's reagent about the same color; wall about 0.25 µ thick.
Basidia 17-22 x 4-5 µ, 4-spored, clavate, yellowish and KOH and Melzer's reagent. Pleurocystidia abundant, 48-72 x 9-15 µ, fusoid-ventricose, apex subacute to obtuse, walls thin and smooth, content ochraceous tawny to yellowish fading to hyaline and homogeneous. Cheilocystidia 28-45 (60) x 8-13 µ, subfusoid with obtuse apex varying to fusoid-ventricose, walls thin, some with debris adhering, content homogeneous. Caulocystidia not studied.
Gill trama a central area of floccose hyphae, the cells yellowish in KOH (poorly revived); subhymenium of narrow gelatinous hyphae in a distinct layer. Pileus cutis a thick gelatinous layer of hyaline to yellowish hyphae 2-4 µ diam.; hypodermial region of bright fulvous hyphae with incrusted walls, cells 4-12 µ diam. Context hyphae interwoven, smooth, yellowish in KOH. Clamp connections present. All hyphae inamyloid. (Above microscopic data all from type).
Habit, Habitat, and Distribution: On conifer debris or near it, fall, Idaho and Washington. Type studied.
Observations: This is another member of the P. spumosa complex which has been named as a distinct species from North America. We suspect that the spotting green when handled is some sort of artifact due to wet weather and the general tendency of olive tints to develop in the context in age. The type specimen reminds one of P. spumosa. We recognized the species here as an aid to future studies, but Smith in all of his collecting in the Northwest has not been able to recognize it on any other feature than the smaller spores. It may well be merely a small spored variety of P. spumosa. P. subfulva has thick-walled pleurocystidia.
We have a number of collections from Idaho (Smith 73387, 73388, 73389, 73415, 73457, 73663) which appear to belong here. Some stained yellow slightly and some did not and all show more fulvous in their coloration than is evident in P. piceina. The following is a description of Smith 73387:
Pileus 3-6 cm broad, broadly convex, expanding to nearly plane, surface viscid (not glutinous), disc ochraceous tawny to dark tawny, glabrous but developing aggregations of fibrils beneath the cuticle, margin pale yellow (about "cartridge-buff"); margin stained sulphur (greenish yellow) where bruised. Context bright yellow, odor pungent, taste mild, FeSO4 olive, Guaiac quickly blue on gills.
Lamellae close to subdistant, adnexed, moderately broad, pale sulphur yellow young, soon duller and near "Verona brown" mature (sordid cinnamon), edges even.
Stipe 5-8 cm long, 4-7 mm thick, equal, interior bright yellow soon fulvous below, surface pale yellow above, paler than "Naphthaline yellow" near apex, fulvous below, glabrescent. Veil thin, yellowish.
Spores 6.5-8 x 4-4.5 µ, smooth, with a minute apical pore; shape in face view oblong to elliptic varying to ovate; in profile somewhat bean-shaped to obscurely inequilateral, color in KOH rusty cinnamon, in Melzer's sol. paler; wall over 0.25 µ thick.
Basidia 4-spored, 20-25 x 6-8 µ, clavate, hyaline to yellow in KOH. Pleurocystidia 40-70(80) x 10-18 µ, fusoid ventricose, apex obtuse to subacute, wall thin, surface smooth, content colloidal as revived ("empty" in fresh material), yellowish to hyaline revived in KOH, nearly hyaline in Melzer's reagent. Cheilocystidia smaller than the pleurocystidia, mostly with yellowish content in KOH. Caulocystidia scattered, clavate to fusoid-ventricose thin-walled, yellow to hyaline.
Gill trama of a central area of more or less parallel hyphae the cells of which finally inflate markedly (+ 15 µ), walls thin to scarcely thickened, hyaline to yellowish, smooth, some ochraceous oleiferous hyphae present; subhymenium a gelatinous zone of hyaline branched hyphae 2-4 µ diam. Pileus cutis a gelatinous layer of ochraceous to hyaline more or less encrusted hyphae 3-6 µ diam.; hypodermium of rusty to ochraceous-fulvous non-gelatinous hyphae with encrusted walls and cells 4-12 (15) µ diam., compactly arranged, walls thin, smooth, pale yellowish olive in KOH. Clamp connections present.
Habit, Habitat, and Distribution: On conifer debris, abundant in the Priest Lake area.
Observations: In this material colors are duller and are more rusty brownish generally than in P. piceina in either the fresh or dried condition. The sulphur stains which develop slowly on the injured pileus margin are not "green" as described for P. subflavida, but close enough to raise doubts, since no truly green-staining fungus has been found. As for the type, the dried specimens cited above resemble those referred to P. spumosa. Because of the slight odor the above collections might be referred to P. graveolens. Because the characters on which P. spumosa, P. graveolens and P. subflavida are distinguished appear to be rather minor, it is urgent that a study in culture be made of the variants which closely resemble P. spumosa.