Polyporus tuberaster

On decaying dead wood, particularly of Fagus or Quercus, with a fan-shaped to infundibuliform pileus 3 to 10 cm across, yellowish-brown with darker fibrillose scales, deeply decurrent, radially elongated white angular pores with tubes up to 0.5 cm deep, an eccentric to lateral cylindrical stipe concolorous with the cap, fungal odour, and mild taste.

Hyphal system dimitic: binding hyphae thick-walled, 1.5 to 3 µm wide, with few branches; generative hyphae hyaline, thin- to slightly thick-walled, 2.5 to 8 µm wide, septate with clamp connections.

Stipe surface with hyphoid terminal fascicles formed by generative hyphae with pale brownish intracellular pigment.

Cystidia absent, but scattered cystidioles 20 to 30 µm long and 5 to 6 µm wide are present in the hymenium.

Basidia cylindrical-clavate, 35 to 45 µm long, 7 to 10 µm wide, clamped at the base, 4-spored.

Spores cylindrical-ellipsoidal, smooth, hyaline, thin-walled, 10 to 16 µm long, 4.5 to 6 µm wide, with a pointed apicular end, containing oil guttules, inamyloid in Melzer's reagent.