# Panaeolus cyanescens
**Panaeolus cyanescens** is a small, dung-inhabiting mushroom in the genus *Panaeolus* that bruises blue when touched and is one of the most potent psilocybin-producing species known. It was described by Saccardo in 1887 and was long placed in the genus *Copelandia*, a name now considered illegitimate; the species currently sits in the family Galeropsidaceae, in the group of bluing, Copelandia-like *Panaeolus* species.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12835877/) • [2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/) It is widely distributed in the tropics and subtropics and is among the hallucinogenic species of the genus, together with *P. subbalteatus* and *P. cambodginiensis*.[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/)
| Key fact | Detail |
|---|---|
| Scientific name | *Panaeolus cyanescens* Sacc., Syll. Fung. 5: 1123 (1887); formerly *Copelandia cyanescens* (Berk. & Broome) Sacc.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12835877/) • [3](https://www.mycolobs-journal.org/Volumi/MycolObs01p44-58.pdf) |
| Family placement | Galeropsidaceae; Copelandia-like species form clade C of *Panaeolus* sensu lato, the main psilocybin-producing group of the genus[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12835877/) |
| Signature character | White-to-gray basidiomes that stain blue to blue-green when bruised or cut; the reaction spreads over several minutes and persists[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12835877/) • [4](https://mushroomidentification.com/encyclopedia/panaeolus-cyanescens/identification-guide) |
| Spore print | Jet black, dense and even; a brown print rules the species out[4](https://mushroomidentification.com/encyclopedia/panaeolus-cyanescens/identification-guide) |
| Habitat | Strict dung fungus on cow and horse dung and heavily dunged pasture soil; essentially never on wood, litter, or bare ground[4](https://mushroomidentification.com/encyclopedia/panaeolus-cyanescens/identification-guide) |
| Chemistry | Contains both psilocybin and psilocin; described as one of the most potent hallucinogenic species in the genus[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/) |
| Distribution | Brazil, India, Hawaii, Indonesia, Italy, the Philippines, Australia, Germany, Japan, Mexico, USA, Hungary, Thailand, Sri Lanka, Venezuela, and South Africa[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/) |
| Genomics | One of only two *Panaeolus* species with a genome sequence available (with *P. papilionaceus*)[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/) |
## Identification
The species is relatively easy to recognize in the wild because its white-to-gray basidiomes turn blue when wounded or touched.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12835877/) Bruised and cut surfaces stain blue to blue-green, sometimes almost teal, with the base and lower stipe usually reacting most strongly; the color change spreads over several minutes and persists, and it is the single most useful macroscopic character separating *P. cyanescens* from every other pale dung *Panaeolus*, all of which stay gray, brown, or unchanged.[4](https://mushroomidentification.com/encyclopedia/panaeolus-cyanescens/identification-guide)
The cap is strongly hygrophanous, meaning it changes color markedly as it dries. As they dry, the delicate cap skin frequently splits into small, angular pieces, and as a result specimens collected in moist and dried states from a single dung pat may be mistaken for separate species.[4](https://mushroomidentification.com/encyclopedia/panaeolus-cyanescens/identification-guide) The gills are strongly mottled, and the spore deposit is jet black; a brown print points instead at the brown-printing lawn genera of similar size and shape.[4](https://mushroomidentification.com/encyclopedia/panaeolus-cyanescens/identification-guide)
## Ecology and distribution
*Panaeolus cyanescens* grows exclusively on dung, occurring on manure from cattle and horses as well as on pasture soil rich in it; with warmth it produces mushrooms one to two days following rainfall, appearing throughout the year in tropical areas and during summer where temperate climates are warm.[4](https://mushroomidentification.com/encyclopedia/panaeolus-cyanescens/identification-guide) Published records place it on several continents, including Brazil, India, Hawaii, Indonesia, Italy, the Philippines, Australia, Germany, Japan, Mexico, the USA, Hungary, Thailand, Sri Lanka, Venezuela, and South Africa.[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/) In Colombia it has been recorded from pastures on cow dung, in páramo, and in disturbed tropical vegetation at elevations from 0 to 2,800 m.[5](https://biodiversidadcop16.foronacionalambiental.org.co/wp-content/uploads/2024/07/Catalogue-of-Fungi-of-Colombia-Biblioteca-.pdf)
## Chemistry and potency
Only four *Panaeolus* species are shown to contain both psilocybin and psilocin: *P. africanus*, *P. cyanescens*, *P. fimicola*, and *P. tropicalis*.[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/) The species is described as one of the most potent hallucinogenic species in the genus.[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/)
**Alkaloid content varies geographically.** Collections of *P. cyanescens* from Hawaii contained significantly higher levels of psilocybin than collections from Australia and Thailand, which barely contained traces.[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/) A phytochemical study of specimens from [Corrientes](https://www.edgepedia.org/corrientes), Argentina, found a very low total alkaloid content of 34.4 µg of bufotenine per mg of extract and an Artemia salina LC50 of 1860 µg/ml, leading the authors to classify those specimens as nontoxic in that model; they noted this did not match earlier reports of high psilocybin and psilocin proportions in the species.[6](https://bicyt.conicet.gov.ar/fichas/produccion/12585403) Misidentification of species is considered possibly the largest problem contributing to confusion in published chemical studies of psychoactive fungi.[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/)
## Similar species and misidentification
In the neotropics *P. cyanescens* can be confused with *P. cambodginiensis* and *P. tropicalis*, from which it is distinguished by its larger spores; those two species have spores of 10–12.5 × 6.5–9 µm and 9–12 × 7–10 µm respectively.[7](https://zenodo.org/records/16794317) *P. cambodginiensis* differs further in overall size, habitat, and the coloration of the apices of its pleurocystidia, and *P. bisporus* is virtually identical macroscopically to *P. cambodginiensis*, *P. cyanescens*, and *P. tropicalis* except that it has exclusively two-spored basidia.[8](https://www.fungipedia.org/media/kunena/attachments/8935/PsilocybinMushroomsoftheWorld.IdentificationGuidebyPaulStametsz-lib.org.pdf) Molecular work has shown the boundary is genuinely blurry: the LSU sequence of a *P. cambodginiensis* strain was consistent with that of *P. cyanescens*, and samples previously estimated as *P. cyanescens* may in fact be *P. cambodginiensis*; in a 2025 survey of 42 psilocybin-producing strains, strains labeled *P. cambodginiensis* classified by ITS as *P. cyanescens* at 99.73 percent identity.[9](https://www.sciencedirect.com/science/article/abs/pii/S0379073805006080) • [10](https://pmc.ncbi.nlm.nih.gov/articles/PMC12015540/)
On lawns, *Panaeolina foenisecii* resembles it in size and shape but deposits a dark brown spore print, has more evenly colored gills, grows in grass rather than on dung, and shows no blue staining.[4](https://mushroomidentification.com/encyclopedia/panaeolus-cyanescens/identification-guide)
## Taxonomy and phylogeny
The name *Copelandia*, under which the bluing dung *Panaeolus* species were long placed, is illegitimate; a 2025 systematic study placed Copelandia-like species in subgenus Bresadolomyces within *Panaeolus* sensu lato, characterized by grayish, relatively fragile basidiomes that turn blue when injured, and named *P. cyanescens* as the best-known species of this main psilocybin-producing group.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12835877/) The genus *Panaeolus* was recently placed in the family Galeropsidaceae, sometimes referred to as tribe Panaeoleae.[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/) A phylogenomic analysis found that *P. cyanescens* and *P. papilionaceus* form the panaeo-clade, which diverged about 87 million years ago and is sister to [Bolbitiaceae](https://www.edgepedia.org/bolbitiaceae).[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12835877/)
DNA-based identification matters for this group because morphology alone is unreliable: a review of the genus found that only 20 of its 77 legitimate species had been sequenced for the ITS region, and a study of *Psilocybe* fungaria found a high rate of misidentification in museum collections and public databases, rendering even names unreliable.[2](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/) • [11](https://pmc.ncbi.nlm.nih.gov/articles/PMC9764976/) DNA tests targeting the ITS-1 locus have been developed to identify members of the genera *Panaeolus* and *Psilocybe* unambiguously, including for forensic purposes.[12](https://www.sciencedirect.com/science/article/pii/S037907380000181X)
## References
1. [Systematic study of Panaeolus (Agaricales, Galeropsidaceae) sensu lato and psilocybin-producing traits of species from China, IMA FUNGUS (2025)](https://pmc.ncbi.nlm.nih.gov/articles/PMC12835877/)
2. [Strauss, Ghosh, Murray & Gryzenhout (2023). Global species diversity and distribution of the psychedelic fungal genus Panaeolus. Heliyon 9(6):e16338](https://pmc.ncbi.nlm.nih.gov/articles/PMC10238702/)
3. [MycolObs 1: 44–58, on the taxonomy of Copelandia and Panaeolus cyanescens](https://www.mycolobs-journal.org/Volumi/MycolObs01p44-58.pdf)
4. [Panaeolus cyanescens Identification Guide, Mushroom Identifier](https://mushroomidentification.com/encyclopedia/panaeolus-cyanescens/identification-guide)
5. [Checklist of Fungi of Colombia](https://biodiversidadcop16.foronacionalambiental.org.co/wp-content/uploads/2024/07/Catalogue-of-Fungi-of-Colombia-Biblioteca-.pdf)
6. [XXIV Congreso Argentino de Toxicología: Fitoquímica y toxicidad del hongo Panaeolus cyanescens recolectado en Corrientes, Argentina, CONICET](https://bicyt.conicet.gov.ar/fichas/produccion/12585403)
7. [Panaeolus cyanescens Sacc., Syll., Zenodo record 16794317](https://zenodo.org/records/16794317)
8. [Stamets, P. Psilocybin Mushrooms of the World: Identification Guide](https://www.fungipedia.org/media/kunena/attachments/8935/PsilocybinMushroomsoftheWorld.IdentificationGuidebyPaulStametsz-lib.org.pdf)
9. [Phylogenetic relationship of psychoactive fungi based on rRNA gene for a large subunit and their identification using the TaqMan assay (II), Forensic Science International](https://www.sciencedirect.com/science/article/abs/pii/S0379073805006080)
10. [Comprehensive analysis of 42 psilocybin-producing fungal strains reveals metabolite diversity and species-specific clusters (2025)](https://pmc.ncbi.nlm.nih.gov/articles/PMC12015540/)
11. [DNA Authentication and Chemical Analysis of Psilocybe Mushrooms Reveal Widespread Misdeterminations in Fungaria and Inconsistencies in Metabolites (2022)](https://pmc.ncbi.nlm.nih.gov/articles/PMC9764976/)
12. [Identification of members of the genera Panaeolus and Psilocybe by a DNA test: A preliminary test for hallucinogenic fungi, Forensic Science International (2000)](https://www.sciencedirect.com/science/article/pii/S037907380000181X)
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*Topic: Encyclopedia › Life and health › Microorganisms and fungi › Fungi and mycology › Basidiomycete taxa › Agaricomycetes › Agaricales › Tricholomataceae and allies › Entolomatoid agaricoid genera*
*Initially written Sep 17, 2026 · Reviewed: Oct 21, 2026 · Edited: Oct 15, 2026; Oct 21, 2026 · Last review: Oct 21, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license