Phylum：Basidiomycota　>>　Class： Basidiomycetes　>>　 Order： Polyporales 
   
 
　BCRC Number： NO BCRC Number!  
   
　Scientific Name： Xenasma pruinosum
 
   
   
　Author：

Xenasma pruinosum (Pat.) Donk, Fungus 27: 25. 1957.
   
 
 
 
 
　Description： Macroscopic characters: Basidiocarps resupinate, effused, adnate, 37–125 μm thick, 1–2 × 4–20 cm, membranous to ceraceous, even, not cracked, felty, opaque to ivory yellow or cartridge buff, pale pinkish buff or light buff when old, not changing color in 5％ KOH; margins thining out, pruinose, white or concolorous. Microscopic characters: Context 37–125 μm thick, without the differentiation of basal layer and intermediate layer of context, only with densely conglutinized matrix and collapse hy-phae (may be of gelatinized), having the thickening of basidiocarps by repetitive context on each of which narrow bands of parallel hyphae and crystals are embedded and darkened; hyphae 1.5–2 μm wide, thin-walled, with indistinct clamp connections, smooth; cystidia dumb-bell-shaped, swelling on both ends, protruding, apex capitate, 26–33 μm high, 5–8 μm wide, middle portion narrow, 3–5 μm wide, thin-walled, smooth, heavily stained by phloxine, basal portion under hymenial layer, radicate or septate, ellipsoid or ovate to oblong when young; others not seen. (Christiansen, p. 103, 1960: basidiospores hyaline, oblong to ellipsoid, on one side straight or slightly depressed, thin-walled, 3–4 × 6–7 μm)
 
 
 
 
 
　Specimens：

Taitung Hsien, Lanyu Hsiang, Tientsu, under the tropical hardwood forests, damp, semishade to full shade, near by a natural reservior which is 65 m in diam., alt. 250–300 m, Aug. 24, 1975, S.-H. Lin (NTU-3815).
 
 
 
　Habitat： On the dead branches of the broad-leaved trees, associated with white rot.
 
 
 
　Distribution：

Europe, North America (?) and Taiwan.
 
 
 
　References：

Lin, SH. 1976.
   
   
   
　Provided：

S. H. Lin
 
 
　Note： In the appearance of cystidia, the species resemble to Hyphodontia laxa (Burt) Hayashi or H. sambuci (Pers.) J. Erikss. However the species is apparently different from them by it having obscure conglutinized context and the membranaous or ceraceous texture. After con-sidering the subgelatinous or waxy texture and radicate cystidia, I am convinced that the material from Taiwan is conspecific with Xenasma pruinosum (Pat.) Donk, although the basidia and basidiospores are not seen.