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Лесные грибы поганки Forest mushrooms toadstool Waldpilze Fliegenpilz

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“Death cap“ redirects here. For the cap formerly worn by British judges during death sentencing, see black cap. Amanita phalloides (/æməˈnaɪtə fəˈlɔɪdiːz/), commonly known as the death cap or the death cap amanita, is a deadly poisonous basidiomycete fungus, one of many in the genus Amanita. Widely distributed across Europe, but now sprouting in other parts of the world, A. phalloides forms ectomycorrhizas with various broadleaved trees. In some cases, the death cap has been introduced to new regions with the cultivation of non-native species of oak, chestnut, and pine. The large fruiting bodies (mushrooms) appear in summer and autumn; the caps are generally greenish in colour with a white stipe and gills. Cap colour is variable, including white forms (see Taxonomy below), and thus not a reliable identifier. These toxic mushrooms resemble several edible species (most notably Caesar’s mushroom and the straw mushroom) commonly consumed by humans, increasing the risk of accidental poisoning. Amatoxins, the class of toxins found in these mushrooms, are thermostable: they resist changes due to heat, so their toxic effects are not reduced by cooking. Amanita phalloides is one of the most poisonous of all known mushrooms. It is estimated that as little as half a mushroom contains enough toxin to kill an adult human. It has been involved in the majority of human deaths from mushroom poisoning, possibly including the deaths of Roman Emperor Claudius in AD 54 and Holy Roman Emperor Charles VI in 1740. It has been the subject of much research and many of its biologically active agents have been isolated. The principal toxic constituent is α-amanitin, which damages the liver and kidneys, causing liver and kidney failure that can be fatal. The death cap has a large and imposing epigeous (aboveground) fruiting body (basidiocarp), usually with a pileus (cap) from 5 to 15 cm (2 to 6 in) across, initially rounded and hemispherical, but flattening with age. The smell has been described as initially faint and honey-sweet, but strengthening over time to become overpowering, sickly-sweet and objectionable. Young specimens first emerge from the ground resembling a white egg covered by a universal veil, which then breaks, leaving the volva as a remnant. The spore print is white, a common feature of Amanita. The transparent spores are globular to egg-shaped, measure 8–10 μm (0.3–0.4 mil) long, and stain blue with iodine. The gills, in contrast, stain pallid lilac or pink with concentrated sulfuric acid. he death cap is native to Europe, where it is widespread. It is found from the southern coastal regions of Scandinavia in the north, to Ireland in the west, east to Poland and western Russia, and south throughout the Balkans, in Greece, Italy, Spain, and Portugal in the Mediterranean basin, and in Morocco and Algeria in north Africa. In west Asia, it has been reported from forests of northern Iran. There are records from further east in Asia but these have yet to be confirmed as A. is ectomycorrhizally associated with several tree species and is symbiotic with them. In Europe, these include hardwood and, less frequently, conifer species. It appears most commonly under oaks, but also under beeches, chestnuts, horse-chestnuts, birches, filberts, hornbeams, pines, and spruces. In other areas, A. phalloides may also be associated with these trees or with only some species and not others. In coastal California, for example, A. phalloides is associated with coast live oak, but not with the various coastal pine species, such as Monterey pine. In countries where it has been introduced, it has been restricted to those exotic trees with which it would associate in its natural range. As the common name suggests, the fungus is highly toxic, and is responsible for the majority of fatal mushroom poisonings worldwide. Its biochemistry has been researched intensively for decades, and 30 grams (1.1 ounces), or half a cap, of this mushroom is estimated to be enough to kill a human. On average, one person dies a year in North America from death cap ingestion. The toxins of the death cap mushrooms primarily target the liver, however other organs such as the kidneys are affected. Symptoms of death cap mushroom toxicity usually occurs six to twelve hours after ingestion. Symptoms of ingestion of the death cap mushroom may include nausea and vomiting, which is then followed by jaundice, seizures, coma which will then lead to death. The mortality rate of ingestion of the death cap mushroom is believed to be around 10-30%. Some authorities strongly advise against putting suspected death caps in the same basket with fungi collected for the table and to avoid even touching them. Furthermore, the toxicity is not reduced by cooking, freezing, or drying. Death caps have been reported to taste pleasant. This, coupled with the delay in the appearance of symptoms—during which time internal organs are being severely, sometim

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