The North American Species of Pholiota

182. Pholiota luteola sp. nov.

Illustrations: Text figs. 402-405.

Pileus 2.5-3.5 cm latus, obtusus demum campanulatus glaber, virgatus, viscidus, aurantiacus vel ad marginem laete luteus. Contextus luteus. Lamellae pallide luteae demum cinnamomeae, confertae, adnatae demum emarginatae, latae. Stipes 3-4 cm longus, 3-5 mm crassus, aequalis, solidus; intus  sursum laete luteus, deorsum olivaceus; fibrillosus. Sporae 6.5-8 x 4-4.5 µ. Pleurocystidia 45-65 x 9-15 µ acuta, fusoidea, tenuitunicata. Specimen typicum in Herb. Univ. Mich. conservatum est; legit prope McCall, Idaho. 17 Sept. 1956. Smith 53487.

Pileus 2.5-3.5 cm broad, obtuse when young, expanding to obtusely conic-campanulate, glabrous but virgate from streaks beneath pellicle, "Xanthine-orange" (bright orange) and disc and streaks, "pale orange-yellow" near margin (bright yellow), margin fringed at first with yellow veil remnants. Context yellow, odor and taste mild.

 Lamellae yellowish pallid when young (paler than context of pileus), near cinnamon-brown mature, close, moderately broad, adnexed.

Stipe 3-4 cm long, 3-5 mm thick at apex, equal, solid becoming hollow, picric yellow within above and in base olivaceous, surface brownish at base, yellowish pallid above, thinly fibrillose from yellow veil.

Spores 6.5-8 x 4-4.5 µ, smooth, apical pore minute, wall thickened (± 0.25 0.3 µ), shape ovate to subelliptic (often tapered slightly at apex) in face view, in profile somewhat bean-shaped to obscurely inequilateral, in KOH rusty pale cinnamon, in Melzer's reagent paler.

Basidia 4-spored 20-25 x 6-7 µ, yellowish in KOH and also in Melzer's reagent; pleurocystidia numerous, 45-65 x 9-15 µ, fusoid to fusoid-ventricose, apex subacute, walls thin and smooth, content homogeneous (or yellow coagulated material present when first revived in KOH). Cheilocystidia similar to pleurocystidia but smaller or some clavate to fusoid and 30-40 x 9-14 µ, content yellow or hyaline, walls thin and smooth, apex obtuse. Caulocystidia 60-100 x 10-18 µ fusoid-ventricose, walls yellowish in KOH and with some adhering material tending to flake off at times, content homogeneous, walls thin.

Gill trama of parallel floccose short-celled hyphae with thin yellowish to hyaline walls in KOH, cells inflated in age; subhymenium a gelatinous narrow zone of hyaline narrow (2-3 µ) hyphae. Pileus cutis a thick gelatinous pellicle with collapsed hyphae scattered through it and these ochraceous in KOH; hypodermial region rusty orange in KOH slowly becoming duller, hyphae 5-12 µ diam. and conspicuously incrusted. Context hyphae of greatly inflated, smooth, yellowish to hyaline thin walls. Clamp connections present. All hyphae inamyloid.

Habit, Habitat, and Distribution: Gregarious on wet conifer wood, near McCall, Idaho. Sept. 17, 1956. Smith 53487, type.

Observations: This is one of the brightly colored species of the subgenus Flammuloides. It is amply distinct from P. spumosa in its bright colors, paler gills when young and more acute pleurocystidia. The species epithet refers to the pale yellow gills.