Russula nigricans

Taxobox
color = lightblue
name = "Russula nigricans"
status = common

---

image_width=250px
regnum = Fungi
divisio = Basidiomycota
classis = Agaricomycetes
ordo = Russulales
familia = Russulaceae
genus = "Russula"
species = "R. nigricans"
binomial = "Russula nigricans"
binomial_authority = (Bull.)Fr.mycomorphbox
name = Russula nigricans
whichGills = adnate
capShape = convex
capShape2=depressed
hymeniumType=gills
stipeCharacter= bare
sporePrintColor=white
howEdible=edible

"Russula nigricans", known as the Blackening russula or Blackening brittle gill, is a gilled fungus found in woodland in Europe. It gains both its common and scientific name from its propensity to turn black from cutting or bruising. It is edible but of indifferent quality.

Taxonomy

It is placed in the "Compactae" group, subsection "Nigricantinae" by Bon.cite book | author = Marcel Bon | year = 1987 | title = The Mushrooms and Toadstools of Britain and North Western Europe | publisher = Hodder and Stoughton | isbn = 0 340 39935 X] It was first described by the French mycologist Pierre Bulliard in 1798 as "Agaricus nigricans", before gaining its current binomial name from the father of mycology, the Swedish mycologist Elias Magnus Fries. Its specific epithet is the Latin "nigricans" 'blackening'.

Description

This is a large member of the genus "Russula", and it has a cap that is dirty white when young, but swiftly turns brown, and then black on aging. It measures 5-20 cm (2-8 in) in diameter. There is usually a large depression in the centre of mature caps, which are three quarter peeling. The stem is white; firm; straight, and thick, and it too blackens with age. The gills 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, and then grey, and black within 20 minutes. The spore print is white, and the warty oval spores measure 7-8 x 6-7 μm.cite book | author = Roger Phillips | year = 2006 | title = Mushrooms | publisher = Pan MacMillan | isbn = 0-330-44237-6|pages=p. 47]

Old specimens are sometimes parasitised by fungi of the genus "Nyctalis", in particular the species "N. parasitica" and "N. asterophora" (The Pick-a-Back Toadstool).

Distribution and habitat

"Russula nigricans" appears in late summer and autumn in both deciduous and coniferous woodland across Britain, Northern Europe, and at least the East Coast of North America. cite book |author=David Arora |year=1986 |title=Mushrooms Demystified |publisher=Ten Speed Press |isbn=0-89815-169-4]

Edibility

This mushroom is edible, but poor. The taste becomes hot over time.

imilar species

"R. anthracina" Romagn., also known as "R. albonigra" (Krombh.) Fries, has closer gills and is far less common. It lacks the red phase of colouration when the flesh is cut.

References