Amanita muscarea

Description:

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 a white egg, covered in the white warty material of the universal veil. Dissecting the mushroom at this stage will reveal a characteristic yellowish layer of skin under the veil which assists in identification. As the fungus grows, the red color 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 color may fade after rain and in older mushrooms. 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. The free gills are white, as is the spore print. The oval spores measure 9–13 by 6.5–9 μm, and are non-amyloid, that is, they do not turn blue with the application of iodine. The stipe is white, 5–20 cm high (2–8 in) by 1–2 cm (0.4–0.8 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

Habitat:

A. muscaria is a cosmopolitan mushroom, native to conifer and deciduous woodlands throughout the temperate and boreal regions of the Northern Hemisphere, including high elevations of warmer latitudes in regions like the Hindu Kush, the Mediterranean and Central America. A recent molecular study proposes an ancestral origin in the Siberian–Beringian region in the Tertiary period before radiating outwards across Asia, Europe and North America. Though generally encountered in autumn, the season can vary in different climates: fruiting occurs in summer and autumn across most of North America, but later in autumn and early winter on the Pacific coast. It is often found in similar locations to Boletus edulis, and may appear in fairy rings. Conveyed with pine seedlings, it has been widely transported into the southern hemisphere, including Australia, New Zealand, South Africa and South America. Ectomycorrhizal, Amanita muscaria forms symbiotic relationships with a wide variety of trees, including pine, spruce, fir, birch, and cedar. Commonly seen under introduced trees, A. muscaria is the fungal equivalent of a weed in New Zealand, Tasmania and Victoria, forming new associations with southern beech (Nothofagus). It is also invading native rainforest in Australia, where it may be displacing native species. Furthermore, it appears to be spreading northwards, with recent reports placing it near Port Macquarie on the New South Wales north coast. Although it has not spread to eucalypts in Australia, it has been recorded associating with them in Portugal