The North American Species of Pholiota

137. Pholiota sienna (Kauff.) comb. nov.

Stropharia sienna Kauffman, Pap. Mich. Acad. Sci. Arts, Papers and Letters 11: 207. 1930.

Illustrations: Text figs. 289-290.

The following description is adopted from Kauffman's original account and maintains his wording to a great extent.

Pileus 4-8 cm broad, fleshy, campanulate-expanded to almost plane, obtuse or obsoletely umbonate, center colored with "burnt sienna" (R), tawny-olive or paler on margin, with a glutinous toughish separable pellicle when wet, at first with veil remnants near the membranous and even margin. Context avellaneous, 2-4 mm thick, odor strong, Inocybe-like or of iodiform; taste tardily disagreeable.

Lamellae adnate with decurrent tooth, becoming slightly decurrent in age, broad, narrowed in front, subventricose, close to crowded, "clay-color" (R) with fuscous tints when mature, edge entire, concolorous.

Stipe 5-7 cm long, 5-8 mm thick, rather slender, curved or flexuous, equal or only slightly enlarged at base, peronate by an appressed fibrillose, rufescent-tinged veil to near apex, with an evanescently fibrillose annulus, apex faintly yellowish, at first stuffed then hollow, whitish to faintly yellowish within.

Spores 6-7 (8) x 4-5 µ, elliptic to oval (almost corn-kernel shaped in one view), fuscous in mass, pale fuscous-purplish under microscope, smooth. Cystidia abundant on side and edges of gills, lanceolate, subventricose below, neck tapering to obtuse apex, hyaline, thin-walled, 60-65 x 9-16 µ; basidia short, 16-18 x 4-5 µ, 4-spored.

Type collected under oak and Douglas fir, Takilma, Oregon, December 2, 1925, C. H. Kauffman.

The type specimens now have dark dull ochraceous tawny gills much as in other species of subg. Flammuloides. The pileus is darker yellow-brown over the disc than over the margin and the latter is not at all virgate-as is true for P. decorata. The spore print described by Kauffman is not with the specimen, in fact we suspect that he observed the color of the spore deposit either on the stipe apex or on spores deposited on a second cap. If such is actually the case this might account for the fuscous color as described by Kauffman. Certainly the basidiocarps now in the type collection belong in Pholiota. Smith's study of the microscopic features of the type follows:

Spores 6-7.5 (8) x 4-5 µ smooth, lacking a distinct apical pore (possibly a minute pore present); shape in face view ovate or varying to elliptic, in profile obscurely inequilateral to slightly bean-shaped; color ochraceous tawny in KOH, paler in Melzer's reagent; wall about 0.25 µ thick.

Basidia 18-20 x 6-7 µ, 4-spored, short-clavate, hyaline in KOH, yellowish in Melzer's reagent. Pleurocystidia 56-70 x 10-14 µ, fusoid-ventricose, with subacute apex, walls often thickened to 1.5 µ ventricose part and smooth, content as revived in KOH, yellowish-brown and granular-amorphous (not a solid inclusion as in chrysocystidia). Cheilocystidia similar to pleurocystidia or shorter and walls often thin. Caulocystidia none found.

Gill trama with a central strand of subparallel hyphae hyaline to  pale yellow in KOH and the hyphae 4-7 µ or more in diam., cells with smooth thin non-gelatinous walls; subhymenium a distinct gelatinous layer of narrow interwoven hyphae. Pileus cutis a thick gelatinous pellicle of narrow (1.5-3 µ) yellowish hyphae more or less appressed; hypodermial zone of hyphae 5-10 µ or more diam. with heavily pigmented walls from rusty brown incrustations. Context hyphae loosely interwoven and floccose, nearly hyaline in KOH, walls thin and smooth. Clamp connections present.

Observations: This species is close to P. avellaneifolia but the latter has grayish gills when young, a yellowish veil, and the context stains pinkish buff when cut.