Amanita muscaria, commonly known as the fly agaric or fly amanita, is a mushroom and psychoactive basidiomycete fungus, one of many in the genus Amanita. Native throughout the temperate and boreal regions of the Northern Hemisphere, it has been unintentionally introduced to many countries in the Southern Hemisphere, generally as a symbiont with pine and birch plantations, and is now a true cosmopolitan species. It associates with various deciduous and coniferous trees.
Although classified as poisonous, reports of human deaths resulting from its ingestion are extremely rare. After parboiling — which weakens its toxicity and breaks down the mushroom's psychoactive substances — it is eaten in parts of Europe, Asia, and North America. Amanita muscaria is noted for its hallucinogenic properties, with its main psychoactive constituent being the compound muscimol. The mushroom was used as an intoxicant and entheogen by the peoples of Siberia, and has a religious significance in these cultures.
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