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Death cap

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iDeath Cap

Image:Amanita phalloides 1.JPG

Conservation status

Secure

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Scientific classification

Kingdom:	Fungi
Division:	Basidiomycota
Class:	Homobasidiomycetes
Subclass:	Hymenomycetes
Order:	Agaricales
Family:	Amanitaceae
Genus:	Amanita
Species:	A. phalloides

Binomial name

Amanita phalloides
(Vaill. ex Fr.) Secr.

Amanita phalloides mycological characteristics:	?
Image:Gills icon.png gills on hymenium
Image:Convex cap icon.png cap is convex
Image:Free gills icon2.png hymenium is free
Image:Ring and volva stipe icon.png stipe has a ring and volva
Image:White spore print icon.png spore print is white
Image:Mycorrhizal ecology icon.png ecology is mycorrhizal
Image:Hazard T.svg edibility: deadly

The Death Cap, Amanita phalloides, is one of numerous species of mushrooms in the genus Amanita, and has an infamous reputation for being one of the most toxic of all types of fungi. It is responsible for the majority of deaths from consumption<ref>Benjamin DR. (1995)Amatoxin syndrome. Mushrooms: poisons and panaceas -- a handbook for naturalists, mycologists and physicians. New York: W H Freeman and Company: 198-241</ref>. Its dangerousness is heightened by its similarity to some widely eaten species. Its scientific name phalloides means penis-shaped.

Widely distributed across the northern hemisphere, the Death Cap has been accidentally introduced further afield into such countries as Australia and New Zealand.

1 Description
- 1.1 Similarity to edible species
2 Distribution and habitat
3 Toxicity
4 Trivia
5 Footnotes
6 External links

[edit] Description

The Death Cap has a large and distinctive fungal fruiting body or basidiocarp, usually with a pileus (cap) from 5 to 15 cm (2-6 in) across, initially rounded and hemispherical but flattening with age. Easily peeled, the cap surface can be olive green or brown with a green to smooth yellow tinge, and is often paler after rain. There is a partial veil, white fine lamellae (gills), and a white 4 to 18 cm long and 1–3 cm-thick stipe (stalk) with an annulus (ring) and a swollen volva (base), which may be hidden by leaf litter. As the volva is a distinctive and diagnostic feature it is important to remove some debris to check for one.<ref>Jordan P & Wheeler S (2001). The Ultimate Mushroom Book. Hermes House.</ref>

The Death Cap also has white gills and a white spore print. An entirely white form (Amanita phalloides var. alba) is also occasionally found.

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.

[edit] Similarity to edible species

Asian immigrants in North America, Europe, and Australia have often mistaken the Death Cap for the edible paddy straw mushroom (Volvariella volvacea) due to their similarity in appearance<ref>Trim GM et. al.(1999).Poisoning by Amanita phalloides ("deathcap") mushrooms in the Australian Capital Territory. Medical Journal of Australia.171: 247-249</ref>. This is a leading cause of mushroom poisoning in the United States. Because of its resemblance to edible mushrooms, it is considered especially dangerous; the Finnish name kavalakärpässieni ("devious fly mushroom") is very apt.

[edit] Distribution and habitat

It is found primarily and originally in Europe but now is also in North America, southeastern Australia<ref>Reid DA. (1980) A monograph of the Australian species of Amanita Pers. ex Hook (Fungi). Australian Journal of Botany - Supplementary Series No. 8: 48</ref><ref>Cole FM. (1993) Amanita phalloides in Victoria. Medical Journal of Australia; 158: 849-850</ref>, South America, Asia, and Africa, typically under oaks, nut trees, other hardwoods and some conifers (for example, pines), usually in autumn to early winter depending on the location.

Initial records from North America were of the similar Amanita brunnescens<ref name = "Litten75">Litten W (1975) The Most Poisonous Mushrooms. Scientific American 232(3)90-101</ref>, which was described in 1918, however A. phalloides was later confirmed in the U.S. in its own right. Other similar species are A. subjunquillea in eastern Asia and A. arocheae with a range extending from Andean Colombia to central Mexico (at least). All these fungi are mycorrhizal.

Amanita phalloides appears to be spreading worldwide, and has been conveyed to new countries with conifers and hardwoods.

[edit] Toxicity

One survivor of Death Cap mushroom poisoning described them as "tasting wonderful." She collected the mushrooms in the wild, mistaking them for some gourmet variety she had recently purchased. In many cases of mushroom poisoning, irreparable damage occurs before the onset of symptoms.

Image:Death Cap Mushroom.jpg

As the common name suggests, it is highly poisonous, and is responsible for the majority of fatal mushroom poisonings worldwide. It contains two types of toxins spread throughout the mushroom thallus: phallotoxins (phalloidin, phalloin, phallisin, phallicidin) and amatoxins (amanitin, amanin, amanullin). The toxin most responsible for the deadly effects of the Death Cap is alpha-amanitin. The poison particularly affects the liver and kidneys; frequently the only treatment for Death Cap poisoning is liver transplant. It is estimated that 30 grams (half of a cap) of this mushroom is enough to kill a human. Poisoning can be treated by intravenous injection of silibinin dihydrogen disuccinate disodium.