The North American Species of Pholiota

124. Pholiota agglutinata sp. nov.

Illustrations: Text figs. 271.

Pileus 1-4 cm latus, late conicus vel plano-umbonatus, pallide fulvus, ad marginem pallide subluteus et appendiculatus. Lamellae adnatae, confertae, latae, albidae demum subfulvae. Stipes 2-4 cm longus, 3-5 mm crassus, aequalis, solidus, intus pallidus, extus fibrillosus, deorsum demum fulvus. Sporae 5.5-6.5 (7) x 3.5-4 µ. Pleurocystidia et cheilocystidia 55-80 x 8-12 (15) µ, ad apicem lata; sub-crassotunicata. Specimen typicum in Herb.Univ. Mich. conservatum est; legit prope Black Lee Creek, Payette National Forest, 31 Aug. 1958. Smith 60691.

Pileus 1-4 cm broad, obtuse with an incurved margin, expanding to broadly conic, or finally plano-umbonate, ochraceous tawny to rusty brown over disc, pale cartridge-buff to whitish toward the margin, viscid, variously virgate-streaked with agglutinated fibrils, margin fringed at first with veil remnants. Context cartilaginous, pallid; odor and taste mild; rusty brown around worm holes, instantly malachite green in FeSO4; context yellow with KOH.

Lamellae squarely adnate, whitish becoming dull rusty brown, close, broad, edges even.

Stipe 2-4 cm long, 3-5 mm thick, equal, solid, pallid within, pith green in FeSO4, fibrillose streaked from veil fibrils over surface, whitish but soon rusty brown in basal area, apex white and silky, scarcely a fibrillose zone left by white veil.

Spores 5.5-6.5 (7) x 3.5-4 µ, smooth, apical pore minute; shape oblong, narrowly elliptic or slightly ovate in face view, in profile subelliptic to obscurely inequilateral; in KOH pale tawny, in Melzer's reagent slightly paler; wall relatively thin (0.25 µ ±).

Basidia 21-24 x 5-6 µ, 2- and 4-spored, clavate, hyaline to yellowish in KOH or in Melzer's reagent. Pleurocystidia abundant, 55-80 x 8-12 (15) µ, narrowly ventricose to subcylindric, with a long flexuous neck 5-7 µ diam. ending in a rounded to obtuse apex, sometimes capitate, wall in neck thickened (0.5-1 µ thick), hyaline to yellowish in KOH, smooth, with a long narrow pedicel. Cheilocystidia similar to pleurocystidia but mostly slightly smaller and neck more often with yellow content. Caulocystidia none.

Gill trama with a floccose central strand of subparallel, thin-walled smooth hyaline to yellowish hyphae, the cells short or greatly elongated, hyphae 3-9 µ wide but in age the cells more inflated; subhymenium of narrow (2-3 µ) gelatinous-interwoven hyphae. Pileus cutis a thick gelatinous layer of hyphae 2-4.5 (5.5) µ diam. with hyaline smooth walls revived in KOH; hypodermium of narrow (3-6 µ), smooth, interwoven, ochraceous to orange-ochraceous hyphae nongelatinous in KOH, the walls thickened slightly (0.5 µ or more). Context hyphae 8-15 µ diam., cells inflated, walls smooth to slightly thickened, hyaline to yellowish in KOH. All hyphae inamyloid. Clamp connections present.

Habit, Habitat, and Distribution: Scattered on a mossy bank, under spruce. Payette National Forest, Idaho, Black Lee Creek, Aug. 31, 1958. Smith 60691 (type), 60706, 60707.

Observations: The narrowly ventricose, greatly elongated pleurocystidia are one of its distinctive features. The virgate pileus, whitish gills when young, sharp FeSO4 reaction of the context, white veil and whitish stipe apex are distinctive field characters along with the terrestrial habitat.