 Description： |
Pileus 4-11 cm in diam., convex to plano-convex, ground color very pale gray with an occasional pale brownish disc, covered with small, felty-fibrillose, appressed voval remnants, remnants whitish at first, very pale yellow brown in age, detersile; margin finely striate, appendiculate. Gills distant, free, white, turn red when bruised; lamellulae truncate. Stem 50-140 × 6-20 mm, tapering toward apex, ground color as pileus, hollow, surface floccosescaly; basal bulb globose to ovoid. Volva adherent, forming a membranous sac, lobed, white. Pileipellis filamentous hyphae interwoven, 3-8 μm diam., moderately branched, slightly gelatinized. Basidia clavate, 35-52 × 10-13 μm, 4- sterigmata, sterigmata 3-5 μm, basal septa without clamp. Basidiospores (9.0-) 9.5-10.5 (-11.0) × (5.0-) 5.5-6.0 (-6.5) μm, Q = 1.46-2.10, elliptical, amyloid, hyaline, smooth, thin- walled. Gill trama bilateral, subhymenium inflated ramose, composed of 2-4 ovate, subglobose to elliptical cells. Volva filamentous hyphae on pileus abundant, 2-8 μm diam., gelatinized, septa without clamp; inflated cells moderately abundant in the upper layer, subglobose, obpyriform to broadly elliptic, up to 16-18 × 11-16 μm , terminal; with clavate to fusiform-elliptical cells, up to 30-64 × 9-16 μm , intercalary or terminal; inner layer intensely gelatinized, usually with inflated hyphae, 6-17 μm diam.; volval remnants at stem base similar to those on pileus, but outside layer with sparsely interwoven hyphae. Stem trama longitudinally oriented inflated cell, cylindro-clavate, clavate to slenderly clavate, up to 98-257 × 14-58 μm, usually at the terminal of filamentous branching hyphae (2-6 μm diam.); interlaced with enormous sphaerocysts. |
| Specimens： |
Taiwan, Nantou: Hui-Sun Forest Experimental Station, alt.1850m, 30 Oct. 1998, Chen CM. 2292; same location, 1 Aug. 2000, Chen CM. 2426; same location, 10 Aug. 2000, Chen CM. 2475. |
| Note： |
A. avellaneosquamosa is closely related to A. peckiana Kauff. and A. volvata (Peck) Martin of section Amidella group, but the three species are distinguishable in the field by the differences in their morphological characters. A. peckiana has an unstriated pileal margin, crowd gills, and pinkish to pinkish-cream color on pileal remnants, while A. volvata has an unstriated to faintly striated pileal margin, crowd gills and floccose patches on pileus. A. avellaneosquamosa is fairly similar in characters to those of Amanitopsis clarisquamosa Imai as described by Imai (1933), but these two species have been confirmed to be the distinct taxa by the molecular phylogenetic method (Weiβ et al. 1998). Also, A. avellaneosquamosa has smaller spores , sub-distant lamellae and longer striations along the pileal margin, as compared to those of A. clarisquamosa. |
|
Phylum：Basidiomycota >> Class： Basidiomycetes >> Order： Agaricales