Russula adusta

Formerly known as Russula nigricans, with a large convex to depressed pileus 5 to 20 cm across, whitish brown with blackish tones more pronounced in the center; pure white spore print; distant lamellae; white stipe blackening upon handling; fruity, unpleasant odor and mild taste.

Cuticle filamentous, formed by cylindrical hyphae 3 to 7 µm wide, interwoven, profusely branched, separated by gelification, with abundant brownish intracellular pigment, pileocystidia absent, septate with simple septa.

Cheilocystidia and pleurocystidia cylindrical, clavate to fusiform, 40 to 60 µm long and 4 to 8 µm wide.

Spores subglobose to ellipsoidal, with short warts only up to 0.4 µm high, 6 to 8 µm long, 6 to 7.5 µm wide, ornamented with warts coalescing into ridges, interconnected but without forming a true reticulum.