Hypomyces chrysospermus

Parasitic fungus associated with Boletales, although also observed parasitizing Paxillus.

Filamentous mycelium composed of hyaline, thin-walled hyphae, 3-4 µm wide, abundantly branched, septate with simple septa (clampless).

Conidia produced in the early stages when the mold is white and cottony: cylindric-ellipsoidal, smooth, hyaline, thin-walled, with homogeneous interior (lacking guttules or vacuoles).

Aleuriospores found in the yellow powdery stage when mature: spherical, thick-walled and coarsely verrucose, striking bright yellow, with numerous darker warts visible across focal planes, containing an abundant quantity of lipids or oil droplets inside.