Macroscopic feat.:

• Cap/Pileus: 8-15 mm diam., conical, papillate, smooth, but striate toward the margin, hygrophanous, brown to yellowish brown, subviscid or lubricous to dry.
• Gills/Lamellae: Adnate, very thin, dark violaceous brown.
• Stem/Stipe: 25-35 x 1-1.5 mm, cylindrical, somewhat bulbous, hollow, whitish to reddish brown, densely covered by floccose, white fibrils of velar origin. Veil inconspicuous in the adult carpophores.
• Context: Whitish, staining blue to dark-blue when injured.
• Odor: And taste not registered.

Microscopic feat.:

• Basidio/Spores: (4.4-) 4.9-5.5 (-6) x 4.4-4.9 x 3.3 - 4 µm, rhomboid in frontal view, subelliptic in lateral view, light brownish chocolate, thick walled and with a broad germ pore.
• Basidia: 11-17 x 4.4-6 µm, two- or four-spored, hyaline, cylindrical-ventricose.
• Pleurocistidia: None.
• Cheilocystidia: 10-18 (-26) x 3.3-6 (-7.7) µm, abundant, forming a sterile band at the edge of the gill, polymorphous, fusoid, ventricose-rostrate, clavate, strangulate or mucronate, hyaline or some brownish.
• Subhymenium: With parallel hyphae, strongly and irregularly pigmented with chocolate brown pigment, 4-25 µm diam; in some parts, a lot of blue pigment can be seen diffused in the KOH between the hyphae.
• Trama: Regular, hyaline or pigmented as the subhymenium, hyphae, 5-20 µm diam, thick walled (1-3.3 µm thick), some are solid.
• Epicutis: Subgelatinized, formed by brown reddish to hyaline hyphae, parallel to the surface.
• Hypodermium: As the subhymenium and trama hyphae.

Habitat: On rotten wood in subtropical forest at 1800 m elevation. Known only from the type locality.

Studied material: PANAMA, Prov. Chiriqui, Cerro Punta, near Nueva Suiza, July 3, 1975, Dumont PA-2074 (Holotype NY; Isotype at ENCB).

Discussion: This species is close to Psilocybe yungensis Sing. S. Smith, but differs in the smaller and brownish cheilocystidia. The brownish cheilocystidia connects Psilocybe dumontii with those species described by Guzmán (1977-A) from the tropical rain forests of Mexico such as Psilocybe singerii Guzmán, Psilocybe weldenii Guzmán and others. The species is named after Dr. K. Dumont, collector of the type material, in recognition of his enthusiastic mycological work in South America.

source - www.mycotaxon.com [7 (2): 240]

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