The North American Species of Pholiota

100a. Pholiota subcastanea sp. nov.

Illustrations: Pl. 48.

Pileus 5-10 cm latus, plano-umbonatus, viscidus, squamosus, subcastaneus, cartilagineus. Lamellae angustae, confertae, fulvo-cinnamomeae, demum maculatae. Stipes 6-12 cm longus, 6-12 mm crassus, durus, fibrosis, pallide argillaceus denum subcastaneo maculatus, squarroso-squamulosus. Annulus laceratus, cinnamomeus. Sporae 5-6 x 3.5-4 µ. Pleurocystidia mucronata. Specimen typicum in Herb. Univ. Mich. conservatum est; legit Sharon Hollow, Mich. 21, Sept. 1967, ad Juglans cinerea; Smith 75074.

Pileus 5-10 cm broad, obtuse, expanding to plano-umbonate or nearly so, surface viscid beneath a layer of squamules over disc, toward margin the squamules more or less triangular and appressed, color of scales dull reddish tawny to russet, ground color pallid becoming cinnamon buff. Context cartilaginous-pliant, pinkish buff to cinnamon buff, with a watery brown line above the gills; odor slightly pungent, taste not distinctive; FeSO4 instantly green.

Lamellae narrow, close, adnexed, seceding, reddish cinnamon when mature and spotted russet where injured, edges even.

Stipe 6-12 cm long, 6-12 mm thick, equal to the slightly enlarged fused base, in consistency very hard and fibrous, yellowish to pinkish buff within but soon russet from the base upward, surface recurved-squamulose with cinnamon buff to "Verona brown" very fine but conspicuous lacterate often recurved scales from base to annulus; annulus ragged, underside separating into two layers and dingy cinnamon, upper layer cinnamon; apex of stipe dingy, ground color below ring pale dull cinnamon, becoming russet from base up where bruised.

Spore deposit "russet" moist, "Verona brown" when moisture has escaped. Spores 5-6 x 3.5-4 µ, wall smooth, scarcely thickened, ±0.25 µ, dull brown in KOH and Melzer's; elliptic in face view, nearly so in profile, no apical pore evident. Pleurocystidia as large chrysocystidia 36-47 x 9-15 µ subclavate-mucronate, hyaline-refractive with even content (in KOH) or with a dark brown content more or less reticulate in some, scarcely projecting. Cheilocystidia 26-42 x 8-13 µ, obtusely fusoid ventricose to narrowly clavate but tapered slightly near apex in some, thin walled, lacking any distinctive content, walls faintly yellowish as first when revived in KOH but fading. Subhymenium gelatinous Pileus cutis a thick gelatinous layer, the hyphae narrow (2-4 µ) and with distinctly outlined walls as revived in KOH, hyaline to yellowish. Hypoderm orange-brown in KOH, of compactly arranged hyphae. Clamp connections present.

Habit, Habitat, and Distribution: Caespitose on a log of butternut (Juglans cinerca), Sharon Hollow, Mich. Sept. 2, 1967. Smith 75074. This species is most similar to P. terrestris but is readily distinct by the colors, color changes and habitat. It is an intermediate between stirps Adiposa and stirps Squarrosoides.