''Psilocybe silvatica'' is a psilocybin mushroom in the section ''Semilanceatae'' of the genus ''

Psilocybe ''Psilocybe'' ( ) is a genus of gilled mushrooms, growing worldwide, in the family Hymenogastraceae. Most or nearly all species contain the psychedelic compounds psilocybin and psilocin. Taxonomy Taxonomic history A 2002 study of the mole ...

''. Psilocybin is the main active compound. The species is closely related to its European twin '' Psilocybe medullosa'', which differs genetically, and the American ''

Psilocybe pelliculosa ''Psilocybe pelliculosa'' is a species of fungus in the family Hymenogastraceae. The fruit bodies, or mushrooms, have a conical brownish cap up to in diameter atop a slender stem up to long. It has a white partial veil that does not leave a ...

'', which can be distinguished by spore size and cheilocystidia shape. Cap: ¼"-13/16" broadly conic to bell shaped, and often with an acute reddish brown umbo. Tawny dark brown when moist, fading to pale yellow brown or gray brown and a striate margin. Surface smooth, viscid when moist from a thin gelatinous pellicle that is barely separable, if at all. Gills: narrowly to broadly attached, close or slightly wider spacing, grayish brown to cinnamon brown and smoky brown at maturity with white gill edges. Stem: ¾" - 3 3/16" tall 1/32-⅛" thick, equal to slightly enlarged at the base, brittle, tubular, and somewhat twisted. Pale to brownish under a whitish fibrillose covering. Partial veil is cortinate, thin to obscure, and soon absent. Shimmery off-white rather flexible stem stains yellowish-brown to deep burgundy-brown sometimes bruising blue where handled. Spores: purple-brown, sub-rhomboid with a germ pore, 6-9.5x4-5.5 µm Habitat:solitary or scattered on wood debris or wood chips or on well decayed conifer. medium elevation moist, partially-shaded woods predominantly beech, birch and maple from a mixed woody debris beneath live feather moss layer or from loose soil sometimes fruiting in clear cuts with Psilocybe pelliculosa. Microscopic features: 4 spored and occasionally 2 spored basidia, cheilocystidia 24-40 × 4.4-8.8 µm enlarged in the middle and tapered to both ends or flask shaped, with a long flexuous neck, 1.6-2.2 µm thick.

Taxonomy

The fungus was first described by American mycologist

Charles Horton Peck Charles Horton Peck (March 30, 1833 – July 11, 1917) was an American mycologist of the 19th and early 20th centuries. He was the New York State Botanist from 1867 to 1915, a period in which he described over 2,700 species of North American fun ...

in 1889 as ''Psathyra silvatica''.

Rolf Singer Rolf Singer (June 23, 1906 – January 18, 1994) was a Germany, German-born mycologist and one of the most important Taxonomy (biology), taxonomists of gilled mushrooms (agarics) in the 20th century. After receiving his Ph.D. at the University ...

and Alexander H. Smith transferred it to ''

'' in 1958.

References

{{Taxonbar, from=Q76831 Entheogens Psychoactive fungi silvatica Psychedelic tryptamine carriers Fungi described in 1889 Fungi of North America