Macrolepiota mastoidea

General: Small parasol for the genus (pileus up to 12-13 cm) with a prominently pointed central umbo, hazel-brown at the disc, cracking into fine scales over a whitish background, stipe smooth and unbanded, sweet nutty taste.

Pileipellis: Cutis with emergent terminal elements up to 150 µm long and 8-11 µm wide, with pale brown intracellular pigment, septate with simple septa (clamp connections absent).

Cheilocystidia: Abundant, clavate, septate, 27-40 x 8-12 µm.

Pleurocystidia: Absent.

Basidia: Clavate, 45-55 x 12-16 µm, base simple (clampless), 4-spored.

Spores: Ellipsoid, smooth, hyaline, thick-walled, 12-17 x 9-11 µm, with an eccentric apiculus and an apical germ pore, containing refractive lipid granules, dextrinoid in Melzer's reagent.