The North American Species of Pholiota

13. Pholiota pseudosiparia sp. nov.

Illustrations. Text figs. 13-15.

Pileus 5-8 mm latus, late convexus, siccus, granulosus, sordide fulvus. Lamellae latae, confertae, adnatae, pallide luteae. Stipes 1-2 cm longus, 0.5 mm crassus, sursum pallide ochraceus, deorsum subfulvus. Sporae 7-7.5 µ longae, 4-4.5, µ crassae. Pleurocystidia desunt. Cheilocystidia 28 -40 x 7-11 µ, filamentoso-capitata. Specimen typicum in Herb. Univ. of Mich. conservatum est; legit prope Pellston, Mich., 6 Juli, 1953 Smith 41513.

Pileus 5-8 mm broad, convex to broadly convex, the margin straight, surface dry and granular from cells of the epithelium, many of these becoming free in the mounts; colors dingy ochraceous to dull tawny and fading to pale yellow or cinnamon buff. Context yellowish, thin, soft, odor and taste none.

Lamellae close broad, adnate, yellowish young, then ochraceous tawny, edges minutely crenulate.

Stipe 1-2 cm long, 0.5 mm thick, equal, pallid ochraceous and pruinose above, dingy tan and pubescent below, the hairs delicate.

Spores 7-7.5 x 4-4.5 µ, oblong to subovate in face view, in profile somewhat bean-shaped, smooth, tawny in KOH and wall slightly thickened (spore not collapsing readily), apex with a minute hyaline spot as a rudimentary pore.

Basidia 4-spored, hyaline to yellowish in KOH, clavate, 26-30 x 5-7 µ. Pleurocystidia none. Cheilocystidia 28-40 x 7-11 µ, flexuous-capitate to narrowly clavate and some fusoid-ventricose, hyaline in KOH, smooth, thin-walled. Caulocystidia abundant, often a terminal cell in a series of 2-3 cells, 26-40 x 7-11 (16) µ, somewhat cystidioid (narrowed to an obtuse apex), walls thin and ochraceous, smooth to minutely asperulate.

Gill trama of inflated hyaline cells with thin smooth walls, hyphae more or less subparallel; subhymenium a narrow indistinct zone. Pileus cutis an epithelium of globose to ovate cells with incrusted pigment, walls yellow in KOH, thin. Clamp connections present. All hyphae inamyloid.

Habit, Habitat, and Distribution: Scattered on hardwood logs, Maple River, Emmet County, Michigan, July 6, 1953, Smith 41513 (type). also 41667 and 73301.

Observations: The distinguishing features are the pileus epithelium of globose disarticulating cells with distinct incrustations of pigment, the large caulocystidia, spores of the P. granulosa type, and cheilocystidia of much the same type as found in P. squamulosa. As dried the color of the basidiocarp is very pale. This species would be best placed in the Flocculina group were it not for the well pigmented spores with the very minute pore. Naucoria mexicana is described as having pallid distant gills in contrast to P. pseudosiparia which has close yellowish gills. The spores of N. mexicana were pale ochraceous tawny under the microscope and no pore was noted under high dry magnifications. A few pleurocystidia similar to the subfilamentose cheilocystidia were seen. Also, Murrill described the stipe as tough and fulvous. We believe that the two species are distinct on the differences indicated and do not accept Singer's statement that N. mexicana is a synonym of Pholiota muricata (Singer, 1963, p. 597). The globose cells of the pileus cutis indicate that both are closely related, but before transferring N. mexicana to Pholiota we would prefer to make a critical study of the Phaeomarasmius-Tubaria problem.