Russula emetica

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Russula emetica

Conservation status
Secure
Scientific classification
Kingdom: Fungi
Division: Basidiomycota
Class: Homobasidiomycetae
Subclass: Hymenomycetes
Order: Russulales
Family: Russulaceae
Genus: Russula
Species: R. emetica
Binomial name
Russula emetica
(Schaeff.: Fr.) Pers.
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Russula emetica
mycological characteristics:
 
gills on hymenium
 

cap is convex

 

hymenium is free

 

stipe is bare

 

spore print is white

 

ecology is mycorrhizal

 

edibility: poisonous

Russula emetica, commonly known as The Sickener, is a basidiomycete mushroom of the genus Russula, one of many species with a predominantly red-coloured cap and white gills and stalk. It gets its common name from its inedibility, as it causes vomiting and diarrhea when consumed. It has an extremely peppery taste, which is said to disappear on cooking, along with its toxicity, though eating it is not recommended.

Contents

[edit] Taxonomy

R. emetica was first described as Agaricus emeticus by Jacob Christian Schaeffer in 1774,[1] before being placed in the new genus Russula by Christian Hendrik Persoon in 1796, where it remains. Its specific epithet is derived from the Ancient Greek emetikos/εμετικος 'emetic' or 'vomit-inducing'.[2] Similarly, its common names of sickener, emetic russula and vomiting russula also refer to this attribute.

The uncommon European subspecies R. emetica longipes is distinguished by its longer stalk and ochre-coloured gills.[3] The paler European mushroom Russula betularum of coniferous forests and moorland is sometimes considered a subspecies.[3]

[edit] Description

The sticky cap is 3-10 cm (1¼-4 in) wide and a bright scarlet or cherry red in colour with finely ridged margins. It is initially convex, then later flat, or depressed. The brittle flesh is white and the taste is very sharp and peppery. The spore print is white, as are the narrowly spaced gills. The stipe is up to 7 cm (3 in) long and 1 cm (½ in) wide, cylindrical and white.[4] The fungus has an unusual fruity smell.

It is one of many red-coloured species of Russula; the related Beechwood Sickener R. mairei is found under beech in Europe. Many, such as the paler R. sanguinea, are inedible, though R. aurata is edible and good: it has a yellow stem, gills and flesh under its red cap.[5] Another inedible species, R. fragilis has notched gills, and its stalk stains blue with naphthol.[6] The red pigments of this and other russulas are water soluble to some degree, and fruiting bodies will often bleach or fade with rain or sunlight.[7]

[edit] Distribution and habitat

The Sickener may be found in wet places in coniferous woodlands in Europe, North Africa, Asia and North America, and can be very common.[3] There is some doubt over the extent of its range in North America, as some sightings refer to the related Russula silvicola; initially the name "Russula emetica" was often applied to any red-capped white russula encountered. Sightings in Australia are now referred to the similarly coloured Russula persanguinea.

[edit] Toxicity

As its name implies, the Sickener is poisonous, though not as dangerous as once described in older mushroom guides. The symptoms are mainly gastrointestinal in nature: diarrhea, vomiting and colicky abdominal cramps. The active agent has not been identified but thought to be sesquiterpenes, which have been isolated from the related genus Lactarius and from Russula sardonia.[8]

The bitter taste does disappear on cooking and it is said to be edible, though not recommended.[6] A study in England and southern Scotland found that the Red Squirrel (Sciurus vulgaris) is known to forage for, store and eat the Sickener.[9]

[edit] External links

[edit] References

  1. ^ In Schaeffer's series on fungi of Bavaria and the Palatinate, Fungorum qui in Bavaria et Palatinatu circa Ratisbonam nascuntur icones. published since 1762.
  2. ^ Liddell, Henry George and Robert Scott (1980). A Greek-English Lexicon (Abridged Edition). United Kingdom: Oxford University Press. ISBN 0-19-910207-4. 
  3. ^ a b c Kränzlin F (1991). Fungi of Switzerland 6: Russulaceae, p. 164. ISBN 3-85604-260-1. 
  4. ^ Carluccio A (2003). The Complete Mushroom Book. Quadrille, p. 71. ISBN 1-84400-040-0. 
  5. ^ Nilson S & Persson O (1977). Fungi of Northern Europe 2: Gill-Fungi. Penguin, p. 118. ISBN 0-14-063006-6. 
  6. ^ a b Zeitlmayr L (1976). Wild Mushrooms:An Illustrated Handbook. Garden City Press, Hertfordshire, p. 92. ISBN 0-584-10324-7. 
  7. ^ Ramsbottom J (1953). Mushrooms & Toadstools. Collins, p. 102. ISBN 1870630092. 
  8. ^ Benjamin, Denis R. (1995). Mushrooms: poisons and panaceas — a handbook for naturalists, mycologists and physicians. New York: WH Freeman and Company, p. 369. ISBN 0-7167-2600-9. 
  9. ^ Lurz PWW, South AB (1998). "Cached fungi in non-native conifer forests and their importance for red squirrels (Sciurus vulgaris L.)". Journal of Zoology, London 246: 468–71. doi:10.1111/j.1469-7998.1998.tb00184.x. 
  • "Danske storsvampe. Basidiesvampe" [a key to Danish basidiomycetes] J.H. Petersen and J. Vesterholt eds. Gyldendal. Viborg, Denmark, 1990. ISBN 87-01-09932-9