Macroscopic feat.:

• Cap/Pileus: (0.7) 1-2.5 (3) cm broad. Conic to campanulate to convex with an acute, extended papilla (up to 4 mm long). Surface slightly viscid when wet, smooth, often ridged halfway to the disc. Reddish brown to orangish brown to yellowish, hygrophanous, fading in drying to straw colored, and bruising blue or blue black.
• Gills/Lamellae: Attachment adnate to adnexed, pale brown to coffee colored, and eventually purplish black at maturity.
• Stem/Stipe: (30) 50-90 (110) mm long by 1-3 mm thick. Equal to slightly thickened near the base, flexuous, sometimes twisted. Whitish to brownish red near the base, easily bruising bluish to bluish black. Partial veil thinly cortinate, fragile, soon disappearing.

Microscopic feat.:

• Basidio/Spores: Dark purplish brown in deposit, rhomboid to subrhomboid, (5) 6.5-8 (9.6) by 4-5.6 µm.
• Basidia: 4-spored, rarely 2-spored.
• Pleurocistidia: 16-36 by 8-12 µm, ventricose to clavate, often irregular.
• Cheilocystidia: (15) 19-35 by 4.4-6.6 µm, lageniform, narrowing into a long neck 1-3 µm, either acute or subcapitate at the apex.

Habitat: Solitary to gregarious in muddy clay soils in subtropical coffee plantations. Found in June and July in Mexico (Puebla, Oaxaca, and Chiapas) and in February in Argentina. Also reported from Brazil and Colombia.

Comment: Moderately active. Specimens from Brazil yielded up to 0.30% psilocybin and 0.30% psilocin (Stijve and de Meijer 1993). A variety of this mushroom, Psilocybe hoogshagenii Heim var. convexa Guzmán is only slightly umbonate, has a convex cap, and is conspecific with Psilocybe semperviva Heim i Callieux. This variety is most common in the state of Puebla, Mexico, and to a lesser degree in the states of Oaxaca and Hidalgo, fruiting from June to August. One of the most unusual looking Psilocybes yet discovered, this mushroom is quite potent. Heim and Hofmann (1958) found 0.60% psilocybin and 0.10% psilocin (as Psilocybe semperviva Heim and Caillieux) from cultivated specimens. Guzmán (1983) reported that this mushroom grows at 1000-1800 meters in elevation (Argentina) and is commonly seen by coffee growers who report massive flushes coming up in unison and soon disappearing. See also Psilocybe brasiliensis.

source - Paul Stamets "Psilocybin Mushrooms of the World"

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