The North American Species of Pholiota

136. Pholiota rubronigra sp. nov.

Illustrations: Pl. 65a.

Pileus 3-8 cm latus, late convexus vel planus, viscidus, fibrillososqamulosus, glabrescens, badius. Contextus albus, fragrans. Lamellae adnatae demum subdecurrentes, latae, confertae, pallidae demum cinnamomeo-brunneae. Stipes 4-6 cm longus, 3-7 mm crassus, ad basin compacte myceliosus, sursum luteus, deorsum fulvus et squamulosus, velum fibrillosum. Sporae 6-8.5 x 4-5 µ. Pleurocystidia 45-75 x 10-15 µ fusoide ventricosa tenuitunicata vel crassotulnicata (1.5 µ). Specimen typicum in Herb. Univ. of Mich. conservatum est; legit prope Trinidad, California, 3 Dec. 1956, Smith 56192.

Pileus 3-8 cm broad, convex, expanding to plane, margin incurved and often appendiculate with veil fragments, color dark vinaceous brown ("Natal-brown") young, in age bay on disc and paler reddish brown on margin, viscid, at first decorated with concentric zones of pallid to yellowish-pallid veil remnants. Context white to pallid; odor distinctly fragrant, taste mild, no color changes observed.

Lamellae adnate becoming subdecurrent, pallid young, dull cinnamon-brown in age, close, only moderately broad, edges even.

Stipe 4-6 cm long, 3-7 mm thick, equal, bulbous from white mycelium at base, apex yellowish to the fibrillose annulus, pallid to grayish fibrillose or subscaly below to the base which darkens to rusty brown within, cortex pallid below at very first. Veil heavy, fibrillose, leaving a semi-persistent ring.

Spores 6-8.5 x 4-5 µ smooth, apical pore present but apex not truncate, shape in face view elliptic to ovate, in profile, slightly bean-shaped to obscurely inequilateral, dull rusty brown in KOH, slowly fading to ochraceous tawny, in Melzer's reagent merely slightly more cinnamon, wall about 0.25 µ thick.

Basidia 25-30 x 6-7 µ, 4-spored, clavate, hyaline to yellowish in Melzer's reagent. Pleurocystidia 45-75 x 10-15 µ, fusoid-ventricose, apex subacute to obtuse and showing a tendency to proliferate, walls thin to 1.5 µ thick in upper part of ventricose portion; content yellowish or rarely dingy amber-brown, colloidal; wall smooth, colorless (somewhat greenish-hyaline) in KOH. Cheilocystidia 33-52 x 8-12 µ, obtusely fusoid to fusoid-ventricose, mostly thin-walled throughout and content similar to that of pleurocystidia. Caulocystidia 34-71 x 10-20 µ, clavate, subpyriform, fusoid or fusoid-ventricose, utriform, etc., thin-walled or wall up to 1.5 (2) µ thick; content homogeneous.

Gill trama a central area of floccose subparallel to interwoven hyphae with long or short cells, the cells (3) 5-15 µ diam., or more (as they inflate); walls thin, smooth, hyaline in KOH; subhymenium a gelatinous layer of somewhat divergent hyphae 2-3 µ diam. and hyaline in KOH. Pileus cutis a thick gelatinous pellicle of narrow (2-3 µ) hyaline gelatinous hyphae; hypodermium of dark rusty brown hyphae with heavy incrustations of pigment, cells 4-10 µ diam. Context hyphae inflated, walls thin, smooth, hyaline in KOH. Clamp connections absent. All hyphae inamyloid.

Habit, Habitat, and Distribution: On pine and redwood logs, Idaho and California, November-December.

Observations: Among the species with thick-walled cystidia P. rubronigra can be recognized by its fragrant odor, some pleurocystidia with walls up to 1.5 µ thick, very dark reddish brown color over the disc of the pileus as dried, and lack of brown squamules over the lower part of the stipe. In the dried state the whole basidiocarp of P. decorata is much paler in color and when fresh its stipe has brown squamules of veil remnants, and it typically lacks a fragrant odor. Both show variation from thin to thick-walled pleurocystidia.

P. vinaceobrunnea lacks a fragrant odor, has pleurocystidia with walls 2-3 µ thick, and no caulocystidia were found in an examination of dried material. Also its cystidia measure 60-115 µ long. P. humii with pleurocystidia having walls to 3 µ thick, has a fragrant odor, and a veil so poorly developed as to scarcely leave a zone of fibrils where it breaks. Also it appears to be a more slender species.

This stirps, with the exception of P. velaglutinosa appears to be a "collective" species, and as indicated in other similar situations, comparative studies in culture are badly needed.

Material Examined: CALIFORNIA: Smith 56059, 56192 (type), 56583, 56647. IDAHO: Smith 69534.