Cyclomyces fuscus
Cyclomyces fuscus Kunze ex Fr. 1830, in Dai, Y.C., Fungal diversity, 45, 131-343 (2010)
Diagnosis: Fruitbody Basidiocarps annual, pileate, broadly attached or flabelliform, usually with a rudimentary stipe, mostly imbricate, soft and without odour or taste when fresh, consistency coriaceous when dry. Pilei projecting up to 2 cm, 7 cm wide and 2 mm thick at base. Pileal surface greyish brown, dark brown to ferruginosus, concentrically sulcate with narrow zones, tomentose; tomentum consisting of bristles; margin acute, entire or lobed, curving down upon drying. Hymenophore surface dark brown to bay, concentrically lamellate, lamellae 4–5 per mm radially; dissepiments thin, entire to lacerate or toothed; sterile margin narrow to almost lacking. Context dark brown, corky, up to 0.5 mm thick, duplex, limited towards upper tomentum by a black zone. Lamellae concolorous with hymenophore surface or slightly paler, coriaceous, up to 1.5 mm thick. Hyphal structure Hyphal system monomitic; generative hyphae simple septate; tissue darkening and slightly dissolved in KOH. Context Hyphae in the lower dense context yellowish brown, fairly thick-walled with a wide lumen, rarely branched, frequently simple septate, flexuous, 3–4.8 μm in diam; hyphae in the black zone dark brown, distinctly thick-walled with a narrow lumen, strongly agglutinated, parallel along the black zone; hyphae in the upper tomentum yellowish brown, thick- to fairly thick-walled with a wide lumen, straight, unbranched, frequently septate, 3–5 μm in diam, some of them parallel, and forming bristles. Lamellae Tramal hyphae yellowish, thin- or fairly thickwalled with a wide lumen, occasionally branched, frequently septate, more or less flexuous, loosely interwoven at base of lamella, straight and parallel towards the edges, 3–4 μm in diam. Setae frequent, distinctly subulate, arising from trama, most part penetrating out of hymenium, slightly bent at base, dark brown, thick-walled, 30–62×5–10 μm. Subhymenium distinct, made up of thin-walled, yellowish, frequently septate hyphae, cell walls of hymenium and subhymenium weakly CB+; cystidia occasionally present or rare, clavate, hyaline, thin-walled, 26–33×3–5 μm; basidia narrowly clavate, with four sterigmata and a simple septum at the base, 12–15×3.3–4.5 μm; basidioles in shape similar to basidia, slightly smaller. Spores Basidiospores oblong-ellipsoid to ellipsoid, hyaline, thin-walled, smooth, IKI–, CB–, (2.3–)2.6–4.2(–4.5)×(1.4–)1.6–2.1(–2.4) μm, L=3.44 μm, W=1.86 μm, Q=1.63–2.03 (n=60/2).
Index Fungorum Number: IF203141
Notes: Cyclomyces fuscus is very easily recognized by its concentric lamellae of hymenophore. It is a rare species occurring in subtropical or tropical forests.
Figure 1. Basidiocarps of Cyclomyces fuscus
Figure 2. Microscopic structures of Cyclomyces fuscus. a basidiospores; b setae; c hyphae from trama; d hyphae from context
Reference:
Dai, Y.C. (2010). Hymenochaetaceae (Basidiomycota) in China. Fungal diversity, 45, 131-343.
Recent Genus
BoreostereumBoidinia
Australovuilleminia
Recent Species
Dictyocephalos attenuatusOliveonia fibrillosa
Tricholomella constricta