The North American Species of Pholiota

24. Pholiota corticola (Murrill) comb. nov.

Naucoria corticola Murrill, Mycologia 4: 77. 1912.

Pileus 1-1.5 cm broad, convex to subexpanded, surface avellaneous, isabelline, innate-fibrillose with slight tufts (resembling Panus stipticus), dry, margin undulate, incurved when young. Context thin.

Lamellae adnate, dull whitish to bay-fulvous, broad, heterophyllus, rather distant. Stipe 1 cm long, more or less 1 mm thick, yellow, cylindric equal, glabrous at apex, whitish pubescent below.

Spores 7-9.5 x 4.5-5 µ, elliptic to ovate in face view, slightly inequilateral in profile, smooth, with a small apical callus, dark reddish tawny under the microscope.

Basidia 18-23 x 5-7 µ, 2- and 4-spored. Pleurocystidia 40-60 x 10-16 µ, irregularly clavate, subcylindric, or narrowly fusoid-ventricose, often with a secondary septum in the upper portion, at times with a brown pigment, walls thin and smooth. Cheilocystidia 37-44 x 5-8 µ, more or less resembling the pleurocystidia, occasionally secondarily septate.

Gill trama subparallel to slightly interwoven, the hyphae 3-7 µ broad and non-gelatinous; subhymenium distinctly gelatinous as revived in KOH. Pileus cuticle a tangled turf of rather long brownish incrusted hyphae. Clamp connections present.

Habit, Habitat, and Distribution: On bark of a stump, Jamaica, December-January. Type studied.

Observations: No caulocystidia were found but so little material was available for examination that we do not regard our observation as final. The structure of the subhymenium is that of a Pholiota rather than a Galerina, especially since the species is not related to those few Galerina species showing a tendency to have a gelatinous subhymenium. This feature is also against placing it in Phaeomarasmius even though the pileus is a trichodermium. The question of the presence of a veil also needs further study from fresh material as the original description does not actually rule out the possibility of a rudimentary veil being present.