Amanita Muscaria: A large, conspicuous mushroom, Amanita muscaria is generally common and numerous where it grows, and is often found in groups with basidiocarps in all stages of development. Fly agaric fruiting bodies emerge from the soil looking like white eggs. After emerging from the ground, the cap is covered with numerous small white to yellow pyramid-shaped warts. These are remnants of the universal veil, a membrane that encloses the entire mushroom when it is still very young. Dissecting the mushroom at this stage reveals a characteristic yellowish layer of skin under the veil, which helps identification. As the fungus grows, the red colour appears through the broken veil and the warts become less prominent; they do not change in size, but are reduced relative to the expanding skin area. The cap changes from globose to hemispherical, and finally to plate-like and flat in mature specimens. Fully grown, the bright red cap is usually around 8–20 cm (3–8 in) in diameter, although larger specimens have been found. The red colour may fade after rain and in older mushrooms.
The free gills are white, as is the spore print. The oval spores measure 9–13 by 6.5–9 μm; they do not turn blue with the application of iodine. The stipe is white, 5–20 cm (2–8 in) high by 1–2 cm (1⁄2–1 in) wide, and has the slightly brittle, fibrous texture typical of many large mushrooms. At the base is a bulb that bears universal veil remnants in the form of two to four distinct rings or ruffs. Between the basal universal veil remnants and gills are remnants of the partial veil (which covers the gills during development) in the form of a white ring. It can be quite wide and flaccid with age. There is generally no associated smell other than a mild earthiness.
Although very distinctive in appearance, the fly agaric has been mistaken for other yellow to red mushroom species in the Americas, such as Armillaria cf. mellea and the edible Amanita basii—a Mexican species similar to A. caesarea of Europe. Poison control centres in the U.S. and Canada have become aware that amarill (Spanish for ‘yellow’) is a common name for the A. caesarea-like species in Mexico. Amanita caesarea is distinguished by its entirely orange to red cap, which lacks the numerous white warty spots of the fly agaric. Furthermore, the stem, gills and ring of A. caesarea are bright yellow, not white.] The volva is a distinct white bag, not broken into scales. In Australia, the introduced fly agaric may be confused with the native vermilion grisette (Amanita xanthocephala), which grows in association with eucalypts. The latter species generally lacks the white warts of A. muscaria and bears no ring.
Amanita muscaria, commonly known as the fly agaric or fly amanita, is a basidiomycete of the genus Amanita. It is also a muscimol mushroom. Native throughout the temperate and boreal regions of the Northern Hemisphere, Amanita muscaria 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.
Arguably the most iconic toadstool species, the fly agaric is a large white-gilled, white-spotted, usually red mushroom, and is one of the most recognizable and widely encountered in popular culture. This includes video game design, such as the extensive use of a recognizable Amanita muscaria in the Mario franchise and its Super Mushroom power up.
Despite its easily distinguishable features, Amanita muscaria is a fungus with several known variations, or subspecies. These subspecies are slightly different, some having yellow or white caps, but they are all usually called fly agarics, and they are most of the time recognizable by their notable white spots. Recent DNA fungi research, however, has shown that some of these variations are not the same species at all, such as the peach-colored fly agaric (Amanita persicina) for example, but the common name ‘fly agaric’ clings on.
Although poisonous, death due to poisoning from A. muscaria ingestion is quite rare. Parboiling twice with water draining weakens its toxicity and breaks down the mushroom’s psychoactive substances; it is eaten in parts of Europe, Asia, and North America. All Amanita muscaria varieties, but in particular A. muscaria var. muscaria, are noted for their hallucinogenic properties, with the main psychoactive constituents being the neurotoxins ibotenic acid and muscimol. A local variety of the mushroom was used as an intoxicant and entheogen by the indigenous peoples of Siberia and by the Sámi, and has a religious significance in these cultures. There has been much speculation on possible traditional use of this mushroom as an intoxicant in other places such as the Middle East, Eurasia, North America, and Scandinavia.