Basidiocarps resupinate, growing inside tree-cavities, up to 5 cm wide and 1-5 cm thick, margin very wide, pore surface tobacco brown, pores angular, 3-4 per mm, tubes oblique, concolorous, up to 8 cm long, context very thin, tobacco brown.
Hyphal system monomitic, generative hyphae 3-6 µm wide.
Hymenial setae scattered, pointed, 20-40 x 4-6 µm.
Setal hyphae abundant in the subiculum and margin, 80-120 x 8-10 µm, in parts inflated to 25 µm, in margin in parts forming dark lines.
Basidia not seen.
Basidiospores pale yellowish, ovoid to ellipsoid, 4-7.5 x 4-5.5 µm.
Substrata. Populus.
Distribution. Known only from Kazakhstan in Central Asia.