fly agaric ; fly amanit

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. Although very distinctive in appearance, the fly agaric has been mistaken for other yellow to red species in the Americas, including Armillaria cf. mellea and the edible Amanita basii—a Mexican species similar to A. caesarea of Europe. Poison control centers in the U.S. and Canada are aware that amarill is a common name for A. caesarea-like species in Mexico, not just the Spanish for 'yellow'. Amanita caesarea can be distinguished as it has an entirely orange to red cap, lacking the numerous white warty spots of the fly agaric. Furthermore the stem, gills and ring are bright yellow, not white. Finally 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

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

Notes:

Amanita muscaria varies considerably in its morphology and many authorities recognize a number of subspecies or varieties within the species. In The Agaricales in Modern Taxonomy, German mycologist Rolf Singer listed three subspecies, though without description: A. muscaria ssp. muscaria, A. muscaria ssp. americana, and A. muscaria ssp. flavivolvata. Contemporary authorities recognize up to seven varieties: ----var. muscaria, the typical red-and-white spotted variety. Some authorities, such as Rodham Tulloss, only use this name for Eurasian and western Alaskan populations. ----var. flavivolvata is red, with yellow to yellowish-white warts, and occurs in the western regions of the North American continent, from southern Alaska down through the Rocky Mountains, through Central America, to at least Andean Colombia. Rodham Tulloss uses this name to describe all "typical" A. muscaria from indigenous New World populations from Alaska southward. ----var. alba, an uncommon fungus, has a white to silvery white cap with white warts but otherwise similar to the usual form. ----var. formosa, has a yellow to orange-yellow cap with yellowish or tan warts and stem. Some authorities use this name for all A. muscaria fitting this description worldwide (cf. Jenkins), others (cf. Tulloss) restrict its use to Eurasian populations. ----Amanita muscaria var. guessowii has a yellow cap surface. Middlesex Fells, Massachusetts var. guessowii is yellow to orange, with center of cap more orange or reddish orange than the outer part. It is found throughout North America, but is most common in northeastern North America, from Newfoundland and Quebec down to Tennessee. Some authorities (cf. Jenkins) treat these populations as part of A. muscaria var. formosa, while others (cf. Tulloss) recognize it as a distinct variety. ----var. persicina is pinkish to orangish "melon" colored with poorly formed or absent remnants of universal veil on the stem and vasal bulb, known from the Southeastern Coastal areas of the U.S.A, described in 1977. ----var. regalis from Scandinavia and Alaska, is liver-brown and has yellow warts. It appears to be uniformly distinctive and some authorities (cf. Tulloss) treat it as a separate species, while others (cf. Jenkins) treat it as a variety of A. muscaria.