The North American Species of Crepidotus

58. Crepidotus appalachianensis sp. nov.

Illustrations: Figs. 14, 121, 122.

Pileus 10-47 mm latus, sessilis, pallidus demum "chamois," brunnaceus squamulosus vel fibrillosus. Lamellae confertae, latae vel medio-latae, albidae deinde "pinkish buff," denique brunnaceae. Sporae 4.5-6 (7) µ globosae vel subglobosae, punctatae. Basidia 26-34 x 5-7 µ, tetraspora. Pleurocystidia 23-50 (60) x (3) 7-10 µ; cheilocystidia 28-48 x 4-10 µ. Cuticula ex hyphis repentibus composita, hyphas incrustatas brunneas sine colore gerens. Fibulae adsunt. Specimen typicum in Herb. Univ. Tenn.; lectum in Cades Cove, Tenn., July 2, 1962, L. R. Hesler 24851.

Pileus 10-47 mm broad, sessile, semiorbicular to flabelliform, convex to subconchate, hygrophanous, pallid to "chamois," brownish-fibrillose or squamulose, margin even. Context thin, whitish; odor mild, taste mild or bitterish.

Lamellae radiating, close, broad or medium broad, whitish then pinkish-buff, finally brownish, edges obscurely fimbriate.

Spores 4.5-6 (7) µ in diameter, globose, at times subglobose, punctate. Basidia 26-34 x 5-7 µ, 4-spored. Pleurocystidia 25-30 (60) x (3) 7-10 µ, obclavate, ventricose, flask-shaped, cylindric, clavate, often tapering above, projecting only slightly; cheilocystidia 28-48 x 4-10 µ, subcylindric, clavate, flask-shaped with a neck. Gill trama subparallel to slightly interwoven, hyphae 5-12 µ broad. Pileus trama interwoven, at times loosely so. Cuticle of repent hyphae, bearing both brown, incrusted hyphae, often in clusters forming scales, and colorless, erect, septate hyphae, the terminal elements at times as pileocystidia . Lactifers present in the trama of the pileus and gills. Clamp connections present.

Habit, Habitat, and Distribution: On hardwood logs, Florida, North Carolina, Tennessee, Kentucky, Ohio, Michigan, May-October.

Material Studied: FLORIDA: Hesler 21441; KENTUCKY: Stevenson (TENN 17492); MICHIGAN: Smith 66275; NORTH CAROLINA: Hesler 18679; OHIO: Cooke (MICH 33763); TENNESSEE: Hesler 12264, 12383, 24851 (type, Cades Cove, Great Smoky Mts. National Park, July 2, 1962).

Observations: This species superficially resembles C. nephrodes, but is chiefly distinguished from it by the presence of pleurocystidia.