Amanita muscaria

Amanita muscaria, commonly known as the fly agaric or fly amanita, is a basidiomycete fungus of the genus Amanita. Its name may come from its historical use to kill flies or from the effects it causes (a medieval belief held that flies could enter the head and cause madness). It is a distinctive, large white-gilled mushroom typically featuring a bright red cap covered with white warts. The complex genetic diversity of A. muscaria suggests that it is a species complex. It is a widely distributed mushroom native to temperate and boreal forests of the Northern Hemisphere, now also naturalised in the Southern Hemisphere, forming symbiotic relationships with various trees and spreading invasively in some regions.

Ingestion of the mushroom can cause poisoning, especially in children and those seeking its hallucinogenic effects, due to psychoactive compounds like muscimol and ibotenic acid; however, fatal poisonings are extremely rare. Parboiling reduces toxicity; drying converts ibotenic acid into muscimol while retaining psychoactive effects. Some cultures use it as food after preparation. Indigenous peoples of Siberia used A. muscaria as an inebriant and entheogen. It has been controversially linked to Santa Claus, Viking berserkers, Vedic soma, and early Christianity, though evidence is sparse and disputed. Its rise in the 2020s as a hallucinogen has led to governmental scrutiny.