Psilocybe uruguayensis

Psilocybe uruguayensis Singer ex Guzmán

Macroscopic feat.:
  • Cap/Pileus: 10-30 mm diam., convex, smooth subviscid, brownish to brownish yellow, not staining green or blue in any part.
  • Gills/Lamellae: Adnate to somewhat sinuate, brownish to violaceous-brown, unicolorous.
  • Stem/Stipe: 40-55 x 2-3 mm, cylindric, not bulbous, smooth, whitish above to brownish or concolorous with pileus below. Annulus membranous, whitish, not staining blue.
  • Context: Whitish, not bluing.
  • Odor: And taste unknown.

Microscopic feat.:
  • Basidio/Spores: (7.5-) 8.8-11.3 (-12.7) x 7-8 (-9) x 6-7 µm, ovoid or subrhomboid in face view, inequilateral, smooth, with thick yellowish brown wall, with truncated apex because of a flattened germ pore.
  • Basidia: 25-30 x 7.5-9.5 µm, including sterigmata which are 4-6 µm long, four-spored, hyaline, subcylindric or vesiculose.
  • Pleurocistidia: None.
  • Cheilocystidia: 24.5-32 x 4.5-9 µm, hyaline, abundant, forming a sterile band at the edge of the gills, ventricose-elongated, somewhat pedicellate, but with a narrow and long neck which is 1.5-2 µm broad, sometimes branched in old specimens.
  • Subhymenium: Pale yellowish brown, without incrusted pigment.
  • Trama: Regular, same color as the subhymenium or hyaline, with inflated hyphae up to 35 µm broad.
  • Epicutis: With a thick layer of gelatinous hyphae, parallel to the surface. Clamp connections present.

Habitat: Gregarious on horse dung, only known from the type locality.

Studied material: URUGUAY, Montevideo, Parque Nacional Carrasco, April 3, 1960, García Zorrón 2439 (Holotype BAFC: Isotypes in MICH and ENCB).

Discussion: The name Psilocybe uruguayensis was given to a collection in BAFC by Singer but remained unpublished. Singer thinks that this species stains blue when fresh. It is close to Psilocybe blattariopsis (Speg.) Sing. but this species has brown pleurocystidia according to a study of the type (Spegazzini 1535, LPS). It is also close to Psilocybe subaeruginascens Höhnel, Psilocybe stuntzii Guzmán & Ott and Psilocybe venenata (Imai) Imaz. & Hongo, but differs in the size of the cheilocystidia and spores; it is interesting to see the geographical distribution of these species; Psilocybe subaeruginascens is only known from Java, Psilocybe venenata from Japan and Psilocybe stuntzii from the NW of North America. (See discussion of Psilocybe blattariopsis).

source - [7 (2): 250-251]

Pictures at

[ Back to lisT ]    [ List of known specieS ]    [ Species albuM ]    [ Suggest species lacK ]
TutorialS ]   [ ForuM ]   [ GalerY (pl) ]   [ TripograM ]   [ PsilosOpediuM ]  

© psilosophy 2001-2022

TutorialS ]   [ ForuM ]   [ GalerY (pl) ]   [ TripograM ]   [ PsilosOpediuM ]  

© psilosophy 2001-2022