Macroscopic feat.:

• Cap/Pileus: 7-10 mm diam., globose-conic to conic-papillate, smooth to somewhat striate at the margin, hygrophanous(?), brown to brownish, viscid (?).
• Gills/Lamellae: Subadnate or sinuate, brownish chocolate with whitish edges.
• Stem/Stipe: 50 x 1-2 mm, cylindric, hollow, flexuosus, whitish to yellowish, covered by floccose white fibrils (it seems to stain blue when injured).
• Context: Whitish.
• Odor: And taste unknown.

Microscopic feat.:

• Basidio/Spores: (7-) 8-9.5 (-11) x 5-6 (-7) x 4-5 µm, subrhomboid in face view, elliptic or subelliptic in side view, thick walled, brownish yellowish, with a broad basal germ pore.
• Basidia: Basidia and pleurocystidia not observed (hymenium collapsed) (it is possible that there are no pleurocystidia).
• Cheilocystidia: 15-28 x 5-8 µm, hyaline, abundant, vesiculose-pyriforme with long neck 8-10 x 1-2 µm, forming a more or less sterile band at the edge of the gill.
• Subhymenium: And trama brownish yellowish with hyphae collapsed.
• Epicutis: Subgelatinized with hyaline elongated hyphae.

Habitat: Solitary on humus in subtropical forests. Known only from the type locality.

Studied material: BRAZIL, Apiaí (Apiahy), Autumn 1881, Spegazzini 1536 (LPS 38307 type).

Discussion: This species is close to Psilocybe mexicana Heim and Psilocybe caerulescens Murr., and seems to be intermediate between them. The size of the spores and the cheilocystidia serves to separate Psilocybe acutipilea from the other two species (see Guzmán 1977-B). It is possible that this species has hallucinogenic properties because of its relationship with those mentioned above that they are use by the Mexican Indians as psychotropic fungi.

source - www.mycotaxon.com [7 (2): 226]

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