Hohenbuehelia atrocoerulea

A Pleurotus-like species with a rudimentary, almost nonexistent stipe, and a greyish-brown cap surface with a whitish margin.

Suprapellis with a layer of hyaline filamentous hyphae, 2-3 µm wide, widely separated by gelification; beneath these lie more compacted hyphae arranged parallelly, 3-5 µm wide, septate with clamp connections at the septa.

Cheilocystidia and pleurocystidia fusiform, very thick-walled (metuloids), with abundant apical crystallizations, 50-70 µm long and 10-15 µm wide.

Basidia clavate, 15-20 µm long and 6-7 µm wide, with 2 or 4 sterigmata (2- or 4-spored).

Spores ellipsoidal, smooth, hyaline, thin-walled, with a lateral apiculus at one end, vacuolar internal content, inamyloid in Melzer's reagent.