Agaricus bisporus

Hyphae of the pileipellis arranged in parallel, fairly broad, without clamp connections and very weakly pigmented, virtually hyaline.

Cheilocystidia very abundant, cylindrical, attenuated at the base and with rounded tips.

Basidia mostly 2-spored, as the specific epithet implies, alternating with some 1-spored basidia.

Spores ovoid to short ellipsoidal, brown, thick-walled, with numerous droplets inside and a very discreet lateral apiculus.