Gymnopilus penetrans

Pileipellis composed of filamentous hyphae, arranged more or less parallel to slightly interwoven, 3-9 µm wide, with faint ochraceous intracellular pigment and abundant yellowish-brown incrustations, septate and with clamp connections at the septa.

Cheilocystidia cylindrical to lageniform, slightly capitate, up to 50 µm long, with faint brownish intracellular pigment.

Pleurocystidia scattered, with morphology and dimensions similar to cheilocystidia.

Basidia clavate, up to 30 µm long, hyaline, with basal clamps, 4-spored.

Spores ellipsoidal, thick-walled and moderately verrucose, golden-yellow under the microscope, with abundant darker warts, an inconspicuous eccentric apiculus at one end, dextrinoid in Melzer's reagent.