Ceratobasidium cornigerum

On very damp decaying wood on the ground, currently Rhizoctonia cornigera according to Index Fungorum, with completely resupinate basidiomes, very thin, greyish to pale cream, surface pruinose, with a thinned, undifferentiated margin.

Hyphal system monomitic, with subicular hyphae hyaline, thin- to slightly thick-walled, 6 to 8 µm wide, branching at right angles, and thin-walled subhymenial hyphae 4 to 5 µm wide; in both cases septate with simple septa (without clamp connections).

Cystidia absent.

Basidia obovoid to slightly stalked, 15 to 25 µm long, 6 to 11 µm wide, with sterigmata up to 10 µm, simple-based and generally four-spored.

Spores ellipsoidal to amygdaliform, smooth, hyaline, thin-walled, with a prominent apiculus at one end, 7.5 to 12 µm long, 5 to 6.5 µm wide, containing oil droplets inside, and inamyloid in Melzer's reagent.

Herbarium material available: JTP2515/25.