- Cap/Pileus: 10-20 mm diam., conical to conico-convex, densely striate for about 2/3 when moist, membranaceous, glabrous, dry, hygrophanous, black-green to deep olive green, fading in aged carpophores.
- Gills/Lamellae: Adnexed or adnato-adnexed, densely crowded, brownish grey or pale brown when young, turning cocoa brown or brown in mature specimens, often with purplish tinge, staining greenish when bruised, edge albofimbriate or concolorous.
- Stem/Stipe: 35-55 by 1-1.5 mm, cylindrical, equal or subbulbous at base, hollow, dark brown below, pale brown towards apex, covered with white fibrils from the veil, dry, base often with white mycelium or white short rhizoids. Stipe turns green in aged carpophores or when bruised.
- Context: Pale green or black green in pileus, brown in stipe especially towards base.
- Odor: And taste absent or acidulous. Chemical reactions on pileus: KOH and HCl - negative
- Basidio/Spores: 5,5-7 (-8) by 4.5-6 by 3.8-4.5 µm, subrhombic (dorsoventral) to elliptical (lateral), yellowish brown (KOH), smooth thick-walled membrane, broad flattened germ pore present.
- Basidia: 13-22 by 4.5-6.5 µm, 4-spored, hyaline.
- Cheilocystidia: (6.5) 10-18 by 6.5-13 µm, globose to broadly fusoid, often with irregular short neck (2,5-4,5 by -2,5 µm), hyaline, thin-walled membrane, forming sterile gill edge.
- Pleurocistidia: Absent.
- Subhymenium: And trama subhyaline, membranes of hyphae irregularly encrusted with yellowish or black (KOH) pigment which reacts pale black-blue (amyloid) in Melzer solution.
- Epicutis: A cutis composed of partly gelatinized parallel hyphae, membranes encrusted with yellowish (KOH) pigment.
- Hypodermium: Of cylindrical to globose cells, membranes hyaline or brownish (KOH), like those of trama. Clamp connections on septae.
Gregarious in small groups, occasionally also solitary, on soil or among litter in tropical or subtropical-montane forests under Castanopsis
, 1000-2400 m a. s. l. Known from Papua New Guinea only.Studied material:
PAPUA NEW GUINEA, Eastern Highlands: Mt. Michael, Frigano, Hut Track; 6. XII. 1971, leg. HORAK (Holotype ZT, 71/385; isotype in ENCB). - Kassem Pass; 13. XII. 1972, leg. HOKAK (ZT, 72/726).Discussion:
This species reminds of the hallucinogenic Psilocybe caerulescens
MURR., reported from the SE of the United States and Mexico (SINGER & SMITH, 1958). The shape and size of the cheilocystidia, however, are distinctly separating the two species.source - www.sydowia.at [31: 49-50]Pictures at www.mushroomobserver.org