Lethal webcaps
Encyclopedia
The Lethal webcaps, two species in the genus Cortinarius
Cortinarius
Cortinarius is a genus of mushrooms. It is suspected to be the largest genus of agarics, containing over 2000 different species and found worldwide. A common feature among all species in the genus Cortinarius is that young specimens have a cortina between the cap and the stem, hence the name,...

, are two of the world's most poisonous mushrooms. The species are the Deadly webcap (Cortinarius rubellus, formerly also known as C. speciosissimus) and the Fool's webcap, C. orellanus.

The mushrooms' characteristics are quite common, making them difficult to identify, which often leads to fatal
Death
Death is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....

 poisonings. Young examples of the species often have a veil between the cap of the mushroom and the stem. This veil looks like a cobweb, hence the name. The veil however partially or completely disappears in older specimens. Some other characteristics for each of the mushrooms are given below.

Deadly webcap (Cortinarius rubellus)

Spore
Spore
In biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles of many bacteria, plants, algae, fungi and some protozoa. According to scientist Dr...

 color
: Rusty brown to orange

Cap: 3–7 cm rusty brown to orange. Often has a steeper and darker colored elevation at the top of the cap, but this varies greatly from specimen to specimen

Gills
Gill (mushroom)
A lamella, or gill, is a papery hymenophore rib under the cap of some mushroom species, most often but not always agarics. The gills are used by the mushrooms as a means of spore dispersal, and are important for species identification...

: Wide gaps between the gills which can be, but are not necessarily, connected to the stem

Location: Rare, but common in temperate parts of northern Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

. Has been encountered as far north as Finnish Lapland.

Habitat
Habitat (ecology)
A habitat is an ecological or environmental area that is inhabited by a particular species of animal, plant or other type of organism...

: Pine
Pine
Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...

 woods with acidic
Soil pH
The soil pH is a measure of the acidity or basicity in soils. pH is defined as the negative logarithm of the activity of hydrogen ions in solution. It ranges from 0 to 14, with 7 being neutral. A pH below 7 is acidic and above 7 is basic. Soil pH is considered a master variable in soils as it...

 soil

Other details: Young specimens contain a pale web between the cap and the stem. Sometimes parts of this web can be seen as a yellow ring on the stem or at the edge of the cap. The fruiting body of the mushroom blossoms from mid-summer to late autumn.

Fool's webcap (Cortinarius orellanus)

Spore color: Rusty brown to orange

Cap: 3–8.5 cm, concave

Gills: Similar to those of the deadly webcap

Location: Common throughout Europe, rare in the northern parts of Europe. Has been observed as far north as southern Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...



Habitat: In forests, around trees where the soil is alkaline or acidic

Other details: Young specimens of the Fool's webcap also contain a web between the cap and the stem that partially or completely disappears as the specimen ages.

Toxicity

Both of these mushrooms can be confused with each other and many incidents of mushroom poisoning
Mushroom poisoning
Mushroom poisoning refers to harmful effects from ingestion of toxic substances present in a mushroom. These symptoms can vary from slight gastrointestinal discomfort to death. The toxins present are secondary metabolites produced in specific biochemical pathways in the fungal cells...

 have occurred where inexperienced mushroom hunters
Mushroom hunting
Mushroom hunting, mushrooming, mushroom picking, and similar terms describe the activity of gathering mushrooms in the wild, typically for eating...

 have confused these mushrooms with edible mushroom
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...

s, such as the chanterelle
Cantharellus
Cantharellus is a genus of popular edible mushrooms, commonly known as chanterelles . They are mycorrhizal fungi, meaning they form symbiotic associations with plants, making them very difficult to cultivate...

, or hallucinogenic mushrooms. One should be especially cautious when picking mushrooms like the cleaned funnel chanterelles
Cantharellus tubaeformis
Craterellus tubaeformis is an edible fungus, also known as Yellowfoot, winter mushroom, or Funnel Chanterelle. It is mycorrhizal, forming symbiotic associations with plants, making it very challenging to cultivate...

 as these mushrooms share the same habitat as the deadly webcap and the fool's webcap. In many incidents where this mushroom has been ingested, death has occurred.

In Poland during the 1950s there was a small epidemic where over 100 people became ill. What caused the illness remained a mystery until 1952 when Polish physician Dr. Stanisław Grzymala discovered that everyone suffering from the illness, which by then had claimed several lives, had eaten the mushroom Cortinarius orellanus.

These mushrooms are sometimes stated to be so poisonous that one could be poisoned even after tasting and spitting out a small piece. The in mice is 12–20 mg per kg body weight. From cases of orellanine-related mushroom poisoning in humans it seems that the lethal dose for humans is considerably lower.

The Deadly webcap and the Fool's webcap both contain the toxin orellanin and orellin , orellinin http://books.google.it/books?id=iaZzj4Rn0QYC&pg=PA501&lpg=PA501&dq=orelline+orellanine+orellinine&source=bl&ots=Prx_hFxXG0&sig=n-c5HJ72ULf6hvr0iMISoXRrYkE&hl=it&ei=EU8gSsf7FJLGsga3qcS3Bg&sa=X&oi=book_result&ct=result&resnum=5 and Cortinarin A,B,C http://books.google.it/books?id=iaZzj4Rn0QYC&pg=PA507&lpg=PA507&dq=cortinarin&source=bl&ots=Prx_hFxVF1&sig=ISaC3svJfCiZlstufhfzxEfkFtY&hl=it&ei=QE4gSuiPLIyfsgbQj_HOBg&sa=X&oi=book_result&ct=result&resnum=1 . A characteristic of orellanin poisoning is the long latency; the first symptoms usually don't appear until 2–3 days after ingestion and can in some cases take as long as 3 weeks. The first symptoms of orellanin poisoning are similar to the common flu
Influenza
Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae , that affects birds and mammals...

 (nausea
Nausea
Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...

, vomiting, stomach pains, headaches, etc.). These symptoms are followed by early stages of renal failure
Renal failure
Renal failure or kidney failure describes a medical condition in which the kidneys fail to adequately filter toxins and waste products from the blood...

 (immense thirst, frequent urination, pain on and around the kidneys), and eventually decreased or nonexistent urine output and other symptoms of renal failure occur. If left untreated death will follow. There is no known antidote
Antidote
An antidote is a substance which can counteract a form of poisoning. The term ultimately derives from the Greek αντιδιδοναι antididonai, "given against"....

 against orellanin poisoning, but early hospitalization and treatment can sometimes prevent serious injuries and usually prevent death. If you suspect orellanin poisoning, acting on it quickly can save your life.

Several more mushrooms in the Cortinarius genus are suspected to contain orellanin or other deadly toxins. Among them are Cortinarius callisteus and Cortinarius limonius.

Nicholas Evans
Nicholas Evans
Nicholas Evans is an English journalist, screenwriter television and film producer and novelist. Evans was born at in Bromsgrove, Worcestershire, and educated at Bromsgrove School but before studying at Oxford University, he served in Africa with the charity Voluntary Service Overseas...

, author of The Horse Whisperer, his wife Charlotte Gordon Cumming
Charlotte Gordon Cumming
Charlotte Gordon Cumming is a contemporary singer-songwriter and music producer, daughter of a Scottish clan chief. She wrote the Sugababes hit "Soul Sound", nominated for MTV Best European Single Award 2001...

, and several of their relatives were poisoned in September 2008 after consuming Cortinarius rubellus and/or Cortinarius speciosissimus that they gathered on holiday. The poisoning was non-lethal, though Evans and the others suffered severe renal damage and had to undergo kidney dialysis. They were informed that they would require kidney transplants and Evans subsequently received a kidney donated by his daughter, Lauren.

See also

  • List of deadly fungi
  • Mushroom poisoning
    Mushroom poisoning
    Mushroom poisoning refers to harmful effects from ingestion of toxic substances present in a mushroom. These symptoms can vary from slight gastrointestinal discomfort to death. The toxins present are secondary metabolites produced in specific biochemical pathways in the fungal cells...

  • Mushroom hunting
    Mushroom hunting
    Mushroom hunting, mushrooming, mushroom picking, and similar terms describe the activity of gathering mushrooms in the wild, typically for eating...


External links

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