The North American Species of Pholiota

163. Pholiota scamba (Fr.) Moser. in Helmut Gams Kleine Kryptogamenflora II. p. 228. 1955.

Agaricus scambus Fries, Epicr. Myc., p. 18-1. 1836-38.
Flammula scamba (Fr.) Saccardo, Syll. Fung. 5: 828. 1887.
Paxillus scambus (Fr.) Quélet, Enchir. Fung., p. 92. 1886.
Naucoria caespitosa Murrill, North Amer. Flora 10: 180. 1917.
Dryophila scamba (Fr.) Kühner & Romagnesi, Flore Anal Champ. Supr., p. 331. 1953.

Illustrations: Text figs. 356-358; pl. 75a, 75b.

Pileus 1.5-2 (3) cm broad, gregarious to more or less caespitose, convex, with or without a low obtuse umbo, expanding to plane or broadly convex, pallid to "pinkish-cinnamon," silky fibrillose, viscid but soon dry, the surface fibrils glistening when dry, margin appendiculate with pinkish-cinnamon fibrils. Context very soft and watery cartilaginous, watery yellowish; odor faintly fragrant, taste mild.

Lamellae adnate with a slight tooth, pale yellow ("cartridge-buff") becoming pallid olive brownish, medium broad, close, edges even, some forked behind, three tiers of lamellulae, narrowed slightly outward, sometimes slightly ventricose.

Stipe 1.5-3 cm long, 1-3 mm thick, often curved, apex pale clear yellow ("sea-foam-yellow"), clay-brown and minutely woolly tomentose or fibrillose-squamulose below, base strigose, equal, solid.

Spores 7-9 (10) x 4.5-5.5 µ, smooth, apex with germ pore and in some apex obscurely truncate (under a 1.4 NA lens), shape in face view ovate to elliptic, in profile somewhat inequilateral to subelliptic; in KOH dull cinnamon, in Melzer's reagent paler and finally pale reddish cinnamon; wall about 0.25 µ thick.

Basidia 18-24 (26) x 7-9 µ, 4-spored, clavate, hyaline to yellowish in KOH or Melzer's reagent. Pleurocystidia 28-40 x 8-14 µ subovate, broadly subfusoid utriform or fusoid-ventricose with a short neck and obtuse apex, thin-walled, in H2O mounts with amorphous debris over apex, in KOH with some refractive particles in neck or an amorphous refractive body filling the tip; smooth, content yellowish and homogeneous in Melzer's reagent. Cheilocystidia 24-33 x 7-10 µ, more frequently ovate to subfusoid than any other shape but generally like the pleurocystidia. Caulocystidia present (rarely) as scattered cells similar to cheilocystidia near stipe apex, walls thin, smooth and yellowish in KOH, content homogeneous.

Gill trama a central area of floccose subinterwoven hyphae 3-5 (10) µ broad (more inflated in age), hyphal walls thin, smooth, hyaline or nearly so in KOH and merely yellowish in Melzer's reagent; subhymenium a relatively broad well-developed layer of interwoven narrow hyaline gelatinous hyphae. Pileus cutis a well developed layer of subgelatinous hyphae 3-5 µ diam. with dull tawny bands and spirals of encrusting material; hypodermial zone of yellow to yellow-brown floccose nearly smooth hyphae more compactly arranged than in the epicuticular layer. Context hyphae interwoven, smooth, cells inflated, walls thin, yellowish to hyaline in KOH, yellowish in Melzer's reagent. Clamp connections present.

Habit, Habitat, and Distribution: On conifers, often mossy, logs and debris, June-October, Michigan, Idaho, and Washington; also in Canada (Ontario).

Observations: The small, pale, viscid, quickly drying pileus and the short, slender, woolly or fibrillose stipe are field characteristics of this species. It has shorter pleurocystidia and cheilocystidia than some of its relatives. European authors make no mention of an odor; in our collections a faint fragrance was noted. The pleurocystidia appear to be intermediate between chrysocystidia and leptocystidia. The very well developed gelatinous subhymenium and the brown spore deposit point clearly to Pholiota as the logical genus for this species.

Material Examined: CALIFORNIA: Smith 3627, 3679, 3768, 3828, 8278, 8644, 8775, 8896, 8966, 9059, 9338, 9373, 9433, 55959, Dec. 1956; IDAHO: Smith 54637, 70661; MICHIGAN: Smith 141349, 43742, 44043, 64692; OREGON: Smith 19661, 19902, 24691, 28552, 28558; WASHINGTON: Murrill 691, (type of Naucoria caespitosa). Smith 13514, 14477, 14504, 14605, 29660, 30884, 40028, 40366, 48254, 48259; CANADA (ONTARIO): Smith 61521; ENGLAND: Smith 63151; SWITZERLAND: Favre 9-5-46.