Rhizopogon luteolus

A semi-hypogeous fungus characteristic of pine forests, potato-like in shape, up to 4 or 5 cm long, yellow, with interior (gleba) white to olive-green with sporulation, mycelial threads on its surface that are more abundant at the base, and without distinct odor or taste.

Outer peridial hyphae cylindrical, thin- to slightly thick-walled, arranged more or less parallel, 3 to 6 µm wide, with copious encrusting yellowish-brown extracellular pigment, septate with simple septa (clampless).

Inner peridial hyphae hyaline, thin-walled, 3 to 8 µm wide; these hyphae, together with those of the internal glebal trama, support the basidia.

Basidia very irregular, subcylindrical, clavate to pyriform, hyaline, 18 to 25 µm long, 6 to 8 µm wide, simple-based (clampless) and generally four-spored.

Spores cylindrical-ellipsoidal, smooth, moderately thick-walled, hyaline or with faint greenish intracellular pigment, 6.5 to 9 µm long, 2.5 to 3 µm wide, with refringent oil droplets inside concentrated at the poles, and inamyloid in Melzer's reagent.