Russula emetica
Encyclopedia
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 partly to disappear on cooking, along with its toxicity, though eating it is not recommended. Mixing one emetica with otherwise edible red Russula will ruin the whole meal, and it is a common reason some do not pick any red Russula-species.
in 1774, 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'. Similarly, its common name
s 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. The paler European mushroom Russula betularum
of coniferous forests and moorland is sometimes considered a subspecies.
is 3–10 cm (1¼–4 in) wide and a bright scarlet or cherry red in colour with finely ridged margins. The cuticle
is readily peeled from the cap. 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. The fungus has an unusual fruity smell.
It is one of many red-coloured species of Russula; the related Beechwood Sickener (R. nobilis) is found under beech in Europe. Many, such as the paler R. sanguinaria
, are inedible, though R. aurea is edible and good: it has a yellow stem, gills and flesh under its red cap. Another inedible species, R. fragilis
has notched gills, and its stalk stains blue with naphthol
. 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.
Spores are roughly spherical, with dimensions of 8–10 µm; they are hyaline
, and covered with small spines (echinulate).
ky abdominal cramps. The active agent has not been identified but thought to be sesquiterpene
s, which have been isolated from the related genus Lactarius
and from Russula sardonia
.
The bitter taste does disappear on cooking and it is said to be edible, though not recommended. A study in England and southern Scotland found that the Red Squirrel
(Sciurus vulgaris) is known to forage for, store and eat the Sickener.
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...
of the genus Russula
Russula
Around 750 worldwide species of mycorrhizal mushrooms compose the genus Russula. They are typically common, fairly large, and brightly colored - making them one of the most recognizable genera among mycologists and mushroom collectors...
, one of many species with a predominantly red-coloured cap
Pileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
and white gills and stalk
Stipe (mycology)
thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...
. It gets its common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
from its inedibility, as it causes vomiting and diarrhea when consumed. It has an extremely peppery taste, which is said partly to disappear on cooking, along with its toxicity, though eating it is not recommended. Mixing one emetica with otherwise edible red Russula will ruin the whole meal, and it is a common reason some do not pick any red Russula-species.
Taxonomy
R. emetica was first described as Agaricus emeticus by Jacob Christian SchaefferJacob Christian Schäffer
Jakob or Jacob Christian Gottlieb Schäffer or Schäffern was a German dean, professor, botanist, mycologist, entomologist, ornithologist and inventor.-Biography:...
in 1774, before being placed in the new genus Russula by Christian Hendrik Persoon
Christian Hendrik Persoon
Christiaan Hendrik Persoon was a mycologist who made additions to Linnaeus' mushroom taxonomy.-Early life:...
in 1796, where it remains. Its specific epithet is derived from the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
emetikos/εμετικος 'emetic' or 'vomit-inducing'. Similarly, its common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
s 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. The paler European mushroom Russula betularum
Russula betularum
Russula betularum is a small, very pale member of the Russula genus of mushrooms. It is usually white to very pale pink, inedible, and grows with birch trees. It is commonly known as the birch brittlegill.-Taxonomy:...
of coniferous forests and moorland is sometimes considered a subspecies.
Description
The sticky capPileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
is 3–10 cm (1¼–4 in) wide and a bright scarlet or cherry red in colour with finely ridged margins. The cuticle
Pileipellis
thumb|300px||right|The cuticle of some mushrooms, such as [[Russula mustelina]] shown here, can be peeled from the cap, and may be useful as an identification feature....
is readily peeled from the cap. It is initially convex, then later flat, or depressed. The brittle flesh
Trama (mycology)
In mycology trama is a term for the inner, fleshy portion of a mushroom's basidiocarp, or fruit body. It is distinct from the outer layer of tissue, known as the pileipellis or cuticle, and from the spore-bearing tissue layer known as the hymenium....
is white and the taste is very sharp and peppery. The spore print
Spore print
thumb|300px|right|Making a spore print of the mushroom Volvariella volvacea shown in composite: mushroom cap laid on white and dark paper; cap removed after 24 hours showing pinkish-tan spore print...
is white, as are the narrowly spaced gills. The stipe
Stipe (mycology)
thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...
is up to 7 cm (3 in) long and 1 cm (½ in) wide, cylindrical and white. The fungus has an unusual fruity smell.
It is one of many red-coloured species of Russula; the related Beechwood Sickener (R. nobilis) is found under beech in Europe. Many, such as the paler R. sanguinaria
Russula sanguinaria
Russula sanguinaria, commonly known as the bloody brittlegill, is a strikingly coloured mushroom, a member of the Russula genus, which has the common name of brittlegills. It is bright blood-red, inedible, and grows in association with coniferous trees...
, are inedible, though R. aurea is edible and good: it has a yellow stem, gills and flesh under its red cap. Another inedible species, R. fragilis
Russula fragilis
The inedible wild mushroom Russula fragilis, which goes by the common name of the fragile brittlegill, is a member of the Russula genus, whose members are commonly known as brittlegills...
has notched gills, and its stalk stains blue with naphthol
Naphthol
Naphthol may refer to:* 1-Naphthol* 2-Naphthol...
. 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.
Spores are roughly spherical, with dimensions of 8–10 µm; they are hyaline
Hyaline
The term hyaline denotes a substance with a glass-like appearance.-Histopathology:In histopathological medical usage, a hyaline substance appears glassy and pink after being stained with haematoxylin and eosin — usually it is an acellular, proteinaceous material...
, and covered with small spines (echinulate).
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. 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.Toxicity
As its name implies, the Sickener is inedible, though not as dangerous as once described in older mushroom guides. The symptoms are mainly gastrointestinal in nature: diarrhoea, vomiting and colicColic
Colic is a form of pain which starts and stops abruptly. Types include:*Baby colic, a condition, usually in infants, characterized by incessant crying*Renal colic, a pain in the flank, characteristic of kidney stones...
ky abdominal cramps. The active agent has not been identified but thought to be sesquiterpene
Sesquiterpene
Sesquiterpenes are a class of terpenes that consist of three isoprene units and have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be acyclic or contain rings, including many unique combinations...
s, which have been isolated from the related genus Lactarius
Lactarius
Lactarius is a genus of mushroom-producing fungi. The genus, collectively known commonly as milk-caps, are characterized by the fact that they exude a milky fluid if cut or damaged...
and from Russula sardonia
Russula sardonia
Russula sardonia, commonly known as the primrose brittlegill, is a mushroom of the Russula genus, which are commonly known as brittlegills. The fruiting body, or mushroom, is a reddish-purple, the colour of blackberry juice, and is found in coniferous woodland in summer and autumn...
.
The bitter taste does disappear on cooking and it is said to be edible, though not recommended. A study in England and southern Scotland found that the Red Squirrel
Red Squirrel
The red squirrel or Eurasian red squirrel is a species of tree squirrel in the genus Sciurus common throughout Eurasia...
(Sciurus vulgaris) is known to forage for, store and eat the Sickener.