Domain: Eukarya
Kingdom: Fungi
Phylum: Basidiomycota
Class: Agaricomycetes
Order: Agaricales
Family: Strophariaceae
Genus: Psilocybe

Cap: 1.5 — 5.5 cm in diameter, conic to obtusely conic to convex, margin turned inwards when young, rarely plane in age, often distinctly rippled, translucent-striate, bruising and aging greenish-bluish about the margin. Dark olive brown to buff brown in color, occasionally steel blue, when dried tending toward copper brown in the center, hygrophanous, fading to milk white, viscid when moist from a gelatinous pellicle, usually separable. Flesh thin, bruises blue easily.
Gills: Close with adnate to sinuate attachment, grayish to cinnamon brown with the edges remaining pallid.
Spores: Dark purplish brown in deposit, oblong in face view or asymmetric ellipsoid (mango form) in side view, (8.5) 9.5 — 13.7(17) x (5) 5.5 — 6.6(7.1) µm.
Stipe: 5 — 7 cm long, 2 — 3 mm thick, equal to subequal, pallid to brownish with white filaments, while often more yellowish towards the apex, distinct rhizomorphs at the base, brittle, stuffed with loose fibers, partial veil evanescent and rapidly becoming indistinguishable, staining blue easily where damaged.
Taste: Farinaceous.
Odor: Farinaceous.
Microscopic features: Basidia 4-spored, pleurocystidia absent, cheilocystidia 20 — 30(40) x 4.5 — 6(9) µm, fusiod with a narrow neck.

The pleated cap margin and small size distinguish this species from related species in the field.

This species is closely related to the subtropical P. aztecorum var. aztecorum.

Commonly eaten hallucinogenic mushroom.