Macroscopic feat.:

• Cap/Pileus: 6-19 mm diam., convex to campanulate, smooth to slightly rimose, faintly striate and transparently when moist, lubricous, hygrophanous, brown reddish to yellow reddish, finally yellow whitish.
• Gills/Lamellae: Adnate or subadnate, ochre violaceous, with whitish edges.
• Stem/Stipe: 20-60 x 1-3 mm, cylindrical, sometimes sinuous, hollow, white to brown reddish, covered with floccose white fibrils, sometimes with a rhizomorphic white prolongation in the soil, up to 20 mm long. Veil white and floccose, distinct annulus absent.
• Context: White in pileus, concolorous with pileus in stipe, staining blue when cut.
• Odor: And taste farinaceous.

Microscopic feat.:

• Basidio/Spores: (6.6-) 7.1-8.8 x (4.9-) 6-6.6 (-7.1) x 4.4-5.5 µm, subrhomboid in frontal view, subelliptic in lateral view, light brownish chocolate or yellowish brown, smooth, thin walled, with a broad germ pore. Spore print violet brown to almost black.
• Basidia: 15-27 x 4.4-8 µm, four-spored, hyaline, vesiculose or subpyriform. Pleurocystidia none.
• Cheilocystidia: 22-30 x 3,3-6,5 µm, abundant, forming a sterile band at the edge of the gills, hyaline, lageniform or fusoid-ampullaceous and mucronate, sometimes branched; the neck 1.6-2.2 µm across.
• Subhymenium: Formed by subglobose, subhyaline elements with yellowish brown irregularly incrusting pigment.
• Trama: Regular, hyaline, with elongate hyphae 15-25 µm diam. with thin wall (1.5 µm thick).
• Epicutis: Subgelatinized, with brownish or hyaline hyphae 2-6 µm broad. Clamp connections present.

Habitat: On clay black soils without herbaceous vegetation, sometimes living together with Aleuria aurantia (Pers. ex Fr.) Fuck., in páramos of Espeletia argentea at 3300-3500 m elevation. Known only from the type locality.

Studied material: COLOMBIA, Department of Cundinamarca, Municipio of Tansa, road La Represa del Rio Neusa to la Torre de Transmisión de TV, July 24, 1971. Guzmán 9146 (Holotype COL; Isotype ENCB); other collections from the same locality are Guzmán 9145. 9l56; 9158 (all in ENCB and COL).

Discussion: Psilocybe columbiana belongs to the Psilocybe zapotecorum group because of its spores and floccose stipe, but differs in the size of the spores and form of the cheilocystidia. It is a hallucinogenic species since it stains blue and has a farinaceous taste and odor.

source - www.mycotaxon.com [7 (1): 237-238]

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