Stereum gausapatum

On bark or decaying wood of oak (Quercus) on the ground, with resupinate to effused-reflexed basidiomes 1 to 2 mm thick; smooth surface, reddish brown when fresh, with an undulate, well-delimited growing margin; elastic in consistency when fresh, hard and brittle when dry.

Hyphal system dimitic, with thick-walled skeletal hyphae, without septa, 3 to 5 µm wide; and hyaline generative hyphae, thin- to moderately thick-walled, 2 to 5 µm wide, septate with simple septa (without clamp connections).

Pseudocystidia very abundant, cylindrical, 120 to 160 µm long, 6 to 10 µm wide, containing copious oily to granular yellowish-brown content inside.

Basidia cylindrical-clavate, 40 to 50 µm long, 6 to 8 µm wide, simple-based, bearing two or four sterigmata (two- or four-spored).

Spores cylindrical-ellipsoidal, smooth, hyaline, thin-walled, 6.5 to 8.5 µm long, 4 to 4.5 µm wide, with an eccentric apiculus at one end, containing granular matter inside, and very weakly amyloid in Melzer's reagent.