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Species Diversity of the Genus Psilocybe (Basidiomycotina, Agaricales, Strophariaceae) in the World Mycobiota, with Special Attention to Hallucinogenic Properties
Abstract
An exhaustive world revision of all names considered in the genus Psilocybe s.l. is presented, of which the hallucinogenic species were treated with special emphasis. Seven hundred eighteen names related to Psilocybe were found reported in the bibliography, of which only 227 are accepted taxa in Psilocybe. The concept of the genus followed here is that of Guzmán 1983; therefore Hypholoma, Melanotus, and Stropharia were excluded. Moreover, 53 species of Psathyrella, many times related with Psilocybe, were also excluded. The hallucinogenic species are 144, which are distributed in all the continents, of which Latin America (including the Caribbae), has the top, with more than 50 species. There are only 22 species in Canada and the US, while Mexico is the country with the higest number in the world, with 53 species. Europe has only 16 species, Asia 15, Africa 4, and Australia and eastern islands 19. Some Psilocybe species are common in several countries or regions, as are P. cubensis and P. subcubensis in all the tropics; P. coprophila in many temperate and tropical regions; P. argentina in several high mountains or in the Austral and Boreal regions; and P. fimetaria and P. semilanceata in Europe, Canada, and the US, but unknown in Mexico.
... The psychedelic drug psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) is a naturally-occurring tryptamine compound found in at least 144 different species of mushrooms worldwide (Guzmán, 2005;Guzmán, Allen, & Gartz, 1998). Psilocybin, which is rapidly metabolized into psilocin in the body, is a serotonin 2A (5-HT 2A ) receptor agonist that can alter perception, emotion, cognition, and sense of self (Hirschfeld & Schmidt, 2021;Holze et al., 2022;Studerus, Gamma, & Vollenweider, 2010). ...
In visual perception, an effect known as surround suppression occurs wherein the apparent contrast of a center stimulus is reduced when it is presented within a higher-contrast surrounding stimulus. Many key aspects of visual perception involve surround suppression, yet the neuromodulatory processes involved remain unclear. Psilocybin is a serotonergic psychedelic compound known for its robust effects on visual perception, particularly texture, color, object, and motion perception. We asked whether surround suppression is altered under peak effects of psilocybin. Using a contrast-matching task with different center-surround stimulus configurations, we measured surround suppression after 25 mg of psilocybin compared with placebo (100 mg niacin). Data on harms were collected, and no serious adverse events were reported. After taking psilocybin, participants (n = 6) reported stronger surround suppression of perceived contrast compared to placebo. Furthermore, we found that the intensity of subjective psychedelic visuals induced by psilocybin correlated positively with the magnitude of surround suppression. We note the potential relevance of our findings for the field of psychiatry, given that studies have demonstrated weakened visual surround suppression in both major depressive disorder and schizophrenia. Our findings are thus relevant to understanding the visual effects of psilocybin, and the potential mechanisms of visual disruption in mental health disorders.
... Deconica is not a very species-rich genus: only 90 names (55 species and 2 varieties), including synonyms and subspecies, were listed in Index Fungorum, since Smith established the subgenus Deconica under Agaricus L. [4,5]. Based on the study of Guzmán, there could be around 133 species of Deconica worldwide [6]. Noordeloos pointed out that there are 24 species in Europe and Ramírez-Cruz treated 47 taxa worldwide [1,2,7]. ...
Deconica is a relatively small genus, with only 90 names recorded in previous research. In this study, four new species of Deconica have been identified based on morphological and phylogenetic evidence from subtropical regions of China. This represents the first discovery of new species of Deconica in China. Morphologically, D. austrosinensis is characterized by medium-sized spores that are elliptical to elongated-ellipsoid in face view, and fusiform to sublageniform and slightly thick-walled pleurocystidia; D. furfuracea is identified by a well-developed and evanescent veil, medium-sized spores that are rhomboid to mitriform in face view, and fusiform to subclavate pleurocystidia that are rare and subacute at apex; D. fuscobrunnea is recognized by dark brown pileus, medium-sized spores that are rhomboid to mitriform in face view, an ixocutis pileipellis, lageniform cheilocystidia with a long neck and lacks pleurocystidia; D. ovispora is distinguished from other Deconica species by medium-sized spores that are ovoid in face view, an ixocutis pileipellis, lageniform cheilocystidia with a long to short neck, and lacks pleurocystidia. Their distinct taxonomic status is confirmed by the positions of the four new species in ITS + LSU phylogenetic trees. Detailed descriptions and morphological photographs of four new species are presented.
... Winkelman (2019a; also see Doyle, 2011/ Saniotis, 2010 shows that the human encounter with psilocybin and it effects as an environmental influence on hominin adaptations and evolution was inevitable across our evolutionary history given the widespread presence of psilocybin-containing mushrooms in most ecozones and across the major inhabitable regions of the earth (Guzmán, 2005(Guzmán, , 2009Guzmán et al., 1998;Stamets, 1996). Acre and Winkelman (2021) review evidence for psilocybin ingestion by our hominin ancestors through triangulation of information from the biogeography of psilocybin-containing fungi, mycophagical, and self-medicative behaviors among primates, and early hominins' paleodiet and paleoecology. ...
Shamanism is a transcultural concept for understanding roles of ritual and psychedelics in the prehistoric origins of religiosity. The origins of religiosity are revealed by parallels of shamanic and chimpanzee collective ritualizations involving group chorusing and drumming with dramatic bipedal displays. This hominid baseline was expanded with mimetic evolution of song, dance and enactment. Psychedelic substances stimulate innate cognitive dispositions manifested in shamanism such as the human-like qualities of spirits, animal identities and other spiritual and mystical experiences. These structural features of consciousness are stimulated by mimetic performances with song, dancing, and drumming; painful and exhausting austerities; and psychedelic substances. These produce altered experiences of the self which are conceptualized within indigenous psychologies as spirits and one’s soul, spiritual allies, and animal powers that can be incorporated into personal powers (i.e., animal transformation). Cross-cultural manifestation of shamanic features reveal that they are based in biology rather than merely cultural traditions.
... El alcaloide triptamínico psilocibina es un metabolito secundario producido por numerosas especies de hongos, principalmente del género Psilocybe (familia Hymenogastraceae) (Van Court et al., 2022), dentro del cual se ha estimado que hay alrededor de 150 especies, ampliamente distribuidas alrededor del mundo (Guzmán, 2005;Strauss et al., 2022). En Colombia se han descrito cerca de 28 especies, siendo Psilocybe cubensis una de las más conocidas (Franco-Molano & Uribe-Calle, 2000;Vasco et al., 2021). ...
La psilocibina es un alcaloide psicodélico producido naturalmente por diversas especies de hongos, especialmente del género Psilocybe, cuyo uso por parte de culturas precolombinas ha sido ampliamente documentado. En la última década, tras años de estigmatización y restricción de uso, se han reactivado las investigaciones sobre las potencialidades terapéuticas de este psicodélico clásico para el tratamiento de múltiples trastornos psiquiátricos, entre ellos el trastorno depresivo mayor. La depresión es un desorden afectivo del estado de ánimo cuya prevalencia mundial se ha incrementado considerablemente en los últimos años y cuyo tratamiento con fármacos convencionales tiene limitada eficacia. Los hallazgos recientes señalan que la psilocibina, en cambio, pueden tener un efecto antidepresivo rápido y sostenido, incluso en individuos con depresión resistente al tratamiento. Aunque aún no se han dilucidado por completo los mecanismos subyacentes a dicho efecto, se ha planteado que estaría mediado por cambios a nivel de neurotransmisión, de plasticidad estructural y funcional y de conectividad de diferentes redes cerebrales. En esta revisión narrativa se presenta una síntesis de la evidencia clínica a favor del efecto antidepresivo de la psilocibina, se exponen algunos mecanismos de acción plausibles que han sido objeto de estudio y se discuten algunos interrogantes y perspectivas del uso del alcaloide en el ámbito clínico.
... Several genera of psychedelic mushrooms containing psilocybin have been documented and include Psilocybe, Panaeolus/Copelandia (Carod-Artal, 2015;Gotvaldová et al., 2022), Inocybe (Gotvaldová et al., 2022;Wieczorek et al., 2015), Pholiotina, Pluteus, Galerina, and Gymnopilus (Gotvaldová et al., 2022) which are largely polyphyletic. Modern attention is largely focused on the genus Psilocybe (Fr.) P. Kumm., which is globally distributed (Carod-Artal, 2015;Guzmán, 2005). Discoveries of novel species and subspecies continue to be described (Borovička et al., 2012;Li et al., 2014;Ma et al., 2014;Ma et al., 2016). ...
Psychedelic mushrooms containing psilocybin and related tryptamines have long been used for ethnomycological purposes, but emerging evidence points to the potential therapeutic value of these mushrooms to address modern neurological, psychiatric health, and related disorders. As a result, psilocybin containing mushrooms represent a re-emerging frontier for mycological, biochemical, neuroscience, and pharmacology research. This work presents crucial information related to traditional use of psychedelic mushrooms, as well as research trends and knowledge gaps related to their diversity and distribution, technologies for quantification of tryptamines and other tryptophan-derived metabolites, as well as biosynthetic mechanisms for their production within mushrooms. In addition, we explore the current state of knowledge for how psilocybin and related tryptamines are metabolized in humans and their pharmacological effects, including beneficial and hazardous human health implications. Finally, we describe opportunities and challenges for investigating the cultural production of psychedelic mushrooms and metabolic engineering approaches to alter secondary metabolite production through biotechnology approaches integrated with machine learning. Ultimately, this critical review of all aspects related to psychedelic mushrooms represents a roadmap for future research efforts that will pave the way to new applications and refined protocols.
... Along with lysergic acid diethylamide (LSD) and N, Ndimethyltryptamine (DMT), psilocybin is considered a classic serotonergic psychedelic. First isolated and identified in 1958 by Albert Hoffman from the fungal species Psilocybe mexicana, psilocybin is the main psychoactive molecule found in close to 300 species of psychoactive mushrooms (Guzmán, 2005). Sacramental use of the Psilocybe genus of gilled fungi in Mesoamerica has been dated to 500 BC (Guerra-Doce, 2015), with shamanic ceremonial healing traditions documented among many Indigenous populations throughout central and southern Mexico, as well as among the Yurimagua of Peru (Schultes & Raffauf 1993, Guzmán, 2008, McKenna & Riba, 2016. ...
A rapid review synthesizing published research on the possible therapeutic applications of psychedelics.
In the past decade, there has been a surge of interest in the therapeutic use of psychedelics, especially in the treatment of depression and addiction, resulting in many new research projects on their properties. This publication outlines the history of scientific experiments conducted with psychedelics in the 1950s and 1960s, as well as their subsequent international outlawing in the 1970s and the resurgence of research into their medical potential with the onset of the 21st century. Additionally, it discusses the potential mechanisms responsible for their therapeutic impact, the dangers accompanying their use, and changes in their legal status in some countries. The text also makes predictions about the development of a new branch of medicine based on the use of classic psychedelics and their new analogs.
Objective:
The authors critically examine the evidence base for psilocybin administered with psychological support/therapy (PST) in the treatment of psychiatric disorders and offer practical recommendations to guide future research endeavors.
Methods:
PubMed was searched for English-language articles from January 1998 to November 2023, using the search term "psilocybin." A total of 1,449 articles were identified and screened through titles and abstracts. Of these, 21 unique open-label or randomized controlled trials (RCTs) were identified that examine psilocybin for the treatment of obsessive-compulsive and related disorders (N=2), anxiety/depression associated with a cancer diagnosis (N=5), major depressive disorder (MDD; N=8), substance use disorders (N=4), anorexia (N=1), and demoralization (i.e., hopelessness, helplessness, and poor coping) in AIDS survivors (N=1).
Results:
The most developed evidence base is for the treatment of MDD (three double-blind RCTs with positive signals spanning a range of severities). However, the evidence is tempered by threats to internal and external validity, including unsuccessful blinding, small samples, large variability in dosing and PST procedures, limited sample diversity, and possibly large expectancy effects. Knowledge of mechanisms of action and predictors of response is currently limited.
Conclusions:
The evidence is currently insufficient to recommend psilocybin with PST as a psychiatric treatment. Additional rigorously designed clinical trials are needed to definitively establish efficacy in larger and more diverse samples, address dosing considerations, improve blinding, and provide information on mechanisms of action and moderators of clinical response. Head-to-head comparisons with other evidence-based treatments will better inform the potential future role of psilocybin with PST in the treatment of major psychiatric disorders.
Two new species of Agaricales, Deconica flavum and Entocybe roseoalbus, are described from Mount Tianmu, Zhejiang Province, Eastern China. Two new species are distinct and monophyletic based on morphology and phylogenetic analyses. Deconica flavum differs from other Deconica species in that the pileus is brow shallow in the center and stipe with yellowish white fibrils, scatted on litter under coniferous and broad-leaved mixed forest at 1162 m. Entocybe roseoalbus is distinguished from other species of Entocybe by nearly blue pileus and pinkish-white stipe, scatted on humus in similar forest conditions at 1025 m. The differences are discussed between the two new taxa and their similar species morphologically, and related species phylogenetically.
The pharmacological treatment of depression consists of taking antidepressant drugs for prolonged periods; its modest therapeutic effect can often be associated with significant adverse effects, while its discontinuation can lead to relapses. Psilocybin is today a novel and breakthrough therapy for major depression. It is a natural alkaloid in Psilocybe mushrooms, which are endemic to Mexico. Research on a larger scale is lacking in various populations, including the Mexican people. This proposal contemplates the experimental design of a preclinical (toxicity and pharmacological evaluation of an extract in mice) and clinical study by including the chemical analysis of a species of Psilocybe cubensis mushroom to characterize its main constituents. The clinical study will consider the safety evaluation by exploring tolerated doses of Psilocybe cubensis by measuring pharmacokinetic parameters after oral administration in healthy adults and an open trial on a sample of patients with major depressive disorder to assess the safety and efficacy of fully characterized Psilocybe cubensis in a two-single doses treatment, (with assisted psychotherapy), compared with the traditional care model at the Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz in Mexico City. This report presents the design of a research project with preclinical and clinical experimental components.
Psilocybe guilartensis (Sect. Brunneocystidiatae) and P. portoricensis (Sect. Cordisporae) are described as new species from the central mountain region of Puerto Rico. Previously only P. cubensis and P. subcubensis were known from the island. The new species are from similar subtropical humid mountainous zone covered by a mesophytic forest, where most hallucinogenic species of Psilocybe are distributed in tropical America.
Psilocybe weilii from Georgia, U.S.A. (Section Cordisporae) is described as a new species. It grows on red clay soil under Liquidambar and Pinus trees. It is related to P. heliconiae, which is known only from a tropical rain forest at Colombia, but differs in the pleurocystidia and cheilocystidia, and in the smaller size of the basidiomata and in the weaker bluing reaction in that species.
An account is given of the blueing, hallucinogenic Psilocybe natalensis which includes a description of the microcharacters based on an examination of the isotype; the microcharacters are illustrated. A more recent gathering from the same general geographical region is also fully described and illustrated for comparison.
Forty-five species of agaricoid fungi described from Brazil by J. P. F. C. Montagne, based upon field-notes and water-colour illustrations provided by H.-A. Weddell, are considered and their taxonomic position established. Revised descriptions and illustrations are provided.