Macroscopic feat.:

• Cap/Pileus: 7-10 mm in diam ., campanulate to subumbonate, subviscid to lubricous, glabrous, even to striate, hygrophanous, yellowish brown, grayish yellow to pale brownish.
• Gills/Lamellae: Subadnate, somewhat thick, grayish brown with violaceous tinges.
• Stem/Stipe: 40-50 x 1-1.5 mm, cylindric, subbulbous, whitish yellow, smooth to fioccose toward the base, without pseudorhiza.
• Context: Of the pileus whitish, thin. All the basidiomata turning blue-green when cut or bruised. KOH stains the pileus dark grayish brown, the stipe vinaceous brown and is negative in the context
• Odor: Farinaceous.

Microscopic feat.:

• Basidio/Spores: (7.5-) 8.5-9 (-11) x 5-6 (-7) µm, slightly subrhomboid in face view, subellipsoid in side view, with a thick yellowish brown wall and with a broad germ pore.
• Basidia: 22-32 x 8-10 µm, 2-, 3- or 4-spored, hyaline, ventricose to subpiriform.
• Pleurocistidia: Absent.
• Cheilocystidia: 13-20 x 3.5-6 µm, hyaline, vesiculose to sublageniform with a short neck less 8 µm long, sometimes irregular in form with a short lateral neck, abundant but the gill edge is heteromorphous and thick.
• Epicutis: A gelatinous layer 25-30 µm, thick, with irregular hyphae in diameter, 5-15 µm wide.
• Hypodermium: With parallel hyphae 2-9 µm in diam. Context of the pileus with subglobose elements, thick-walled (1-1.5 µm thick), with brown incrusted pigment.
• Trama: Gill trama parallel, hyphae irregular in diameter, hyaline or with brown pigment incrusted on the wall. Clamp connections present.

Habitat: Caespitose in soil, in a meadow with grazing grasses, in subtropical zone, at 1100 m ait. Known only from the type locality.

Studied material: COLOMBIA, Departamento Antioquia, Municipio Porce, near the road Medellín to Amalfi, zone of Puente Gabino, Aug. 31, 1990, Guzmán 29561-B (holotype HUA, isotype XAL).

Discussion: This species is close to Psilocybe acutipilea (Speg.) Guzmán, known only from Brazil, of which it differs by the not papillate pileus and not caespitose habit and by the neck of the cheilocystidia (8-10 µm long) (Guzmán, 1983). Psilocybe subacutipilea belongs to Sect. Mexicana.

source - www.mycotaxon.com [51: 230-231]

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