Postia ptychogaster

Species restricted to conifer wood, especially spruce (Picea), with irregular, resupinate basidiomata up to 4 cm long and 1 cm thick, white to pale cream, finely pilose surface, with 2 to 4 angular pores per mm and tubes up to 4 mm deep; the anamorphic state (Ptychogaster fuliginosus) forms subglobose, tomentose masses 2 to 4 cm across, white turning brown from chlamydospore accumulation.

Hyphal system monomitic; generative hyphae hyaline, thin-walled, subicular hyphae arranged more or less parallel, 4 to 6 µm wide, septate with clamp connections.

Cystidia and other sterile hymenial elements absent.

Chlamydospores arising from swellings of subicular hyphae, ellipsoidal, thick-walled, yellowish under the microscope, 5 to 9 µm long and 4 to 6 µm wide.

Basidia clavate, 15 to 20 µm long, 3.5 to 5 µm wide, clamped at the base, 4-spored.

Spores ellipsoidal, smooth, hyaline, thin-walled, 3.5 to 5.5 µm long, 2 to 3 µm wide, practically homogeneous inside, inamyloid in Melzer's or IKI reagent.