''Russula xerampelina'', also commonly known as the shrimp russula, crab brittlegill, or shrimp mushroom, is a

basidiomycete Basidiomycota () is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred to as the "higher fungi") within the kingdom Fungi. Members are known as basidiomycetes. More specifically, Basid ...

mushroom A mushroom or toadstool is the fleshy, spore-bearing Sporocarp (fungi), fruiting body of a fungus, typically produced above ground on soil or another food source. ''Toadstool'' generally refers to a poisonous mushroom. The standard for the n ...

of the brittlegill genus ''

Russula ''Russula'' is a very large genus composed of around 750 worldwide species of fungi. The genus was described by Christian Hendrik Persoon in 1796. The mushrooms are fairly large, and brightly colored – making them one of the most recognizable ...

''. Two subspecies are recognised. The

fruiting bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...

appear in coniferous woodlands in autumn in northern Europe and North America. Their

caps Caps are flat headgear. Caps or CAPS may also refer to: Science and technology Computing * CESG Assisted Products Service, provided by the U.K. Government Communications Headquarters * Composite Application Platform Suite, by Java Caps, a Java ...

are coloured various shades of wine-red, purple to green. Mild tasting and

edible An edible item is any item that is safe for humans to eat. "Edible" is differentiated from " eatable" because it does not indicate how an item tastes, only whether it is fit to be eaten. Nonpoisonous items found in nature – such as some mushroo ...

, it is one of the most highly regarded brittlegills for the table. It is also notable for smelling of shellfish or crab when fresh.

Taxonomy

''Russula xerampelina'' was originally described in 1770 as ''Agaricus xerampelina'' from a collection in

Bavaria Bavaria, officially the Free State of Bavaria, is a States of Germany, state in the southeast of Germany. With an area of , it is the list of German states by area, largest German state by land area, comprising approximately 1/5 of the total l ...

by the German mycologist

Jacob Christian Schaeffer Jacob, later known as Israel, is a Patriarchs (Bible), Hebrew patriarch of the Abrahamic religions. He first appears in the Torah, where he is described in the Book of Genesis as a son of Isaac and Rebecca. Accordingly, alongside his older frate ...

, who noted the colour as ''fusco-purpureus'' or "purple-brown". It was later given its present binomial name by Swedish mycologist

Elias Magnus Fries Elias Magnus Fries (15 August 1794 – 8 February 1878) was a Swedish mycologist and botanist. He is sometimes called the Mycology, "Linnaeus of Mycology". In his works he described and assigned botanical names to hundreds of fungus and li ...

. Its

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

is taken from the

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

meaning "colour of dried vine leaves", ''xeros'' meaning "dry", and ''ampělinos'' or "of the vine". Two subspecies have been recognised, var. ''xerampelina'' and var. ''tenuicarnosa'', with thinner flesh in the cap and the stipe. The name ''R. erythropoda'' is now considered a

synonym A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

, and former subspecies ''R.'' (''xerampelina'' subsp.) ''amoenipes'' (originally named by

Henri Romagnesi Henri Charles Louis Romagnesi (7 February 1912 – 18 January 1999) was a French mycologist who was notable for a thorough review and monograph of the agaric genus ''Entoloma'' (or ''Rhodophyllus'' as it was known in the early 20th century), as w ...

) now a separate species. A former variety with a greenish cap, ''R. xerampelina'' var. ''elaeodes'', is now classified as ''R. clavipes''. As the first defined species, it gives its name to the section ''Xerampelinae'', a group of related species within the genus ''Russula'', occasionally all termed ''R. xerampelina'' in the past.

Common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...

s include shrimp mushroom, shrimp Russula, crab brittlegill, and shellfish-scented Russula.

Description

''Russula xerampelina'' has a characteristic odour of boiled crab or shrimp. Trimethylamine and its precursor, trimethylamine , are the source of this mushroom’s distinct odour. The

cap A cap is a flat headgear, usually with a visor. Caps have crowns that fit very close to the head. They made their first appearance as early as 3200 BC. The origin of the word "cap" comes from the Old French word "chapeau" which means "head co ...

is wide, domed, flat, or with a slightly depressed centre, and sticky. The colour is variable, most commonly purple to wine-red, or greenish, and darker towards the centre of the cap. There are fine grooves up to 1 cm long running perpendicular to the margin. The stipe is long, wide, cylindrical, white or sometimes with a reddish blush, bruising brown. The

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

have a mild to rather bitter taste, narrowly spaced, and turn creamy-yellow on aging specimens. The

spore print 300px, Making a spore print of the mushroom ''Volvariella volvacea'' shown in composite: (photo lower half) mushroom cap laid on white and dark paper; (photo upper half) cap removed after 24 hours showing warm orange ("tussock") color spore print. ...

is creamy-yellow to

ochre Ochre ( ; , ), iron ochre, or ocher in American English, is a natural clay earth pigment, a mixture of ferric oxide and varying amounts of clay and sand. It ranges in colour from yellow to deep orange or brown. It is also the name of the colou ...

. The oval spores measure 8.8–9.9 by 6.7–7.8

μm The micrometre (Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System ...

and are covered with 1 μm spines. This ''Russula'' has been divided into several similar species by some mycologists. However, they all have the singular dark green colour reaction to iron salts (

iron(II) sulfate Iron(II) sulfate or ferrous sulfate (British English: sulphate instead of sulfate) denotes a range of salts with the formula Fe SO4·''x''H2O. These compounds exist most commonly as the heptahydrate (''x'' = 7), but several values for ...

) when applied to the flesh and smell of shellfish. This aroma is quite distinct and becomes stronger with age.

Similar species

More reddish-capped forms could be confused with the sickener ('' R. emetica''), although the latter always has a white stipe and gills; greener-capped species may resemble '' R. aeruginea''. Many other species in the genus are similar, e.g. '' R. graveolens'', but most lack the seafood smell. '' Russula olivacea'' has a more velvety cap.

Distribution and habitat

''Russula xerampelina'' is widely distributed; quite common in northern

temperate In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ran ...

zones, and often ranging into the

Arctic Circle The Arctic Circle is one of the two polar circles, and the northernmost of the five major circle of latitude, circles of latitude as shown on maps of Earth at about 66° 34' N. Its southern counterpart is the Antarctic Circle. The Arctic Circl ...

, it also ranges south to

Costa Rica Costa Rica, officially the Republic of Costa Rica, is a country in Central America. It borders Nicaragua to the north, the Caribbean Sea to the northeast, Panama to the southeast, and the Pacific Ocean to the southwest, as well as Maritime bo ...

. In North America, it appears from July to October to the east and October to January in the west. It grows solitary, or in groups with

conifer Conifers () are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a sin ...

s, and seems to have a preference for

Douglas fir The Douglas fir (''Pseudotsuga menziesii'') is an evergreen conifer species in the pine family, Pinaceae. It is the tallest tree in the Pinaceae family. It is native to western North America and is also known as Douglas-fir, Douglas spruce, Or ...

, or more rarely

pine trees A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. ''World Flora Online'' accepts 134 species-rank taxa (119 species and 15 nothospecies) of pines as cu ...

larch Larches are deciduous conifers in the genus ''Larix'', of the family Pinaceae (subfamily Laricoideae). Growing from tall, they are native to the cooler regions of the northern hemisphere, where they are found in lowland forests in the high la ...

. It is sometimes found in

deciduous In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

woods, such as

beech Beech (genus ''Fagus'') is a genus of deciduous trees in the family Fagaceae, native to subtropical (accessory forest element) and temperate (as dominant element of Mesophyte, mesophytic forests) Eurasia and North America. There are 14 accepted ...

and

oak An oak is a hardwood tree or shrub in the genus ''Quercus'' of the beech family. They have spirally arranged leaves, often with lobed edges, and a nut called an acorn, borne within a cup. The genus is widely distributed in the Northern Hemisp ...

. Variety ''tenuicarnosa'' has been found on sandy soils under pine in Slovakia and northern Italy in

Trentino Trentino (), officially the Autonomous Province of Trento (; ; ), is an Autonomous province#Italy, autonomous province of Italy in the Northern Italy, country's far north. Trentino and South Tyrol constitute the Regions of Italy, region of Tren ...

Uses

The flavor is mild. This russula is considered one of the best

species of its genus, although the shellfish smell will persist even when cooking. This is less pleasant in older specimens.''Mitchell Beazley Publishers ''> The young caps are said to be superb stuffed with any suitable ingredients, and are rarely maggoty.

References

* "Danske storsvampe. Basidiesvampe" key to Danish basidiomycetesJ.H. Petersen and J. Vesterholt eds. Gyldendal. Viborg, Denmark, 1990.

External links

Rogers Mushrooms - ''Russula xerampelina''
{{Taxonbar, from=Q302097 xerampelina Edible fungi Fungi of Europe Fungi of North America Fungi described in 1774 Taxa named by Jacob Christian Schäffer Fungus species