''Russula adusta'', commonly known as the blackening brittlegill or blackening russula, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of gilled

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 ...

. It is a member of the ''

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 ...

'' subgenus ''Compactae''. 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 brown to gray and somewhat shiny, with a mild taste and, reportedly, an odor of empty wine barrels. It has a propensity to turn black from cutting or bruising and has white

spores In biology, a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plant ...

. Similar species include '' Russula albonigra'' and '' R. densifolia''. ''Russula adusta'' is found in woodlands of Europe and North America, growing under

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 ...

Taxonomy

''Russula adusta'' was first described by the French mycologist Pierre Bulliard in 1785 as ''Agaricus nigricans'', before gaining its current binomial name from the 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 ...

Description

This is a large member of the genus ''

'', and it has a

that is dirty white when young, but swiftly turns brown, and then black on aging. It measures in diameter. There is usually a large depression in the centre of mature caps, which are three quarter peeling. The

stem Stem or STEM most commonly refers to: * Plant stem, a structural axis of a vascular plant * Stem group * Science, technology, engineering, and mathematics Stem or STEM can also refer to: Language and writing * Word stem, part of a word respon ...

is white, firm, and straight, measuring long and wide; it too blackens with age. 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 ...

are off-white initially, very widely spaced, and are adnate. These turn red; then grey, and finally black, when bruised. The flesh, which has a fruity smell, when cut turns pale

Indian red Indian Red is traditionally sung at the beginning and at the end of gatherings of Mardi Gras Indians in New Orleans. It is a traditional chant that may have been first recorded in 1947 by Danny Barker Daniel Moses Barker (January 13, 1909 – ...

, and then grey, and black within 20 minutes. 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 white, and the warty oval spores measure 7–8 x 6–7

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 ...

. Old specimens are sometimes parasitised by fungi of the genus '' Asterophora'' or ''Nyctalis'', in particular the species ''N. parasitica'' and ''N. asterophora'' (the pick-a-back toadstool).

Similar species

Species that also bruise red then black include '' Russula acrifolia'' and '' R. dissimulans''. '' Russula albonigra'' has closer gills and is far less common. It bruises directly to black, lacking the red intermediary phase.

Distribution and habitat

''Russula adusta'' appears in late summer and autumn in both deciduous and coniferous woodland, under conifer trees, across Britain, northern Europe, and North America. In North America, it appears in the

Pacific Northwest The Pacific Northwest (PNW; ) is a geographic region in Western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though no official boundary exists, the most common ...

and northern California from October to February.

Toxicity

The species contains toxins which could cause gastrointestinal upset.

References

External links

Rogers Mushrooms – ''Russula adusta''
ia the

Wayback Machine The Wayback Machine is a digital archive of the World Wide Web founded by Internet Archive, an American nonprofit organization based in San Francisco, California. Launched for public access in 2001, the service allows users to go "back in ...

Savuhapero, svedkremla
via the Wayback Machine {{Taxonbar, from=Q1784176, from2=Q96738896 adusta Fungi of Europe Fungi of North America Fungus species