Russula delica
Encyclopedia
Russula delica is a mushroom
that goes by the common name
of milk-white brittlegill, and is a member of the Russula
genus, all of which are collectively known as brittlegills. It is mostly white, with brownish cap
markings, and a short robust stem
. It is edible
, but poor in taste, and grows in mixed woods, in autumn. It can be confused with certain white Lactarius
species.
in 1838, its specific epithet delica is Latin
for "weaned". Older names include Christian Hendrik Persoon
's Lactarius piperatus var. exsuccus.
This species has seen many taxonomic
changes over the years. Many variants, and species have been separated from the true form, for various and myriad reasons. Notably Russula chloroides is given species status by some authorities, because of the narrow blue/green zone at the stem apex of some specimens. Gill spacing, and gill depth has also thrown many finds into doubt, in the past.
Mycologist John Burton Cleland
collected a form he described in 1935 as R. delica from under eucalypt
s in the Mount Lofty Ranges
in South Australia, however, this was reclassified as a new species R. marangania in 1997 by Cheryl Grgurinovic.
s (fruiting bodies) of Russula delica seem loath to leave the soil, and are often found half buried. As a result, the caps
often traps the surrounding leaf debris on their rough surfaces. The cap can be 16 cm (6.3 in) in diameter. It is white, usually tinged with ochre or brown, with an inrolled margin, which usually remains white. At first it is convex, but later flattens, and is often funnel shaped. The firm, white stipe
is short and stout, measuring 2–6 cm (0.8–2.4 in) high and 2–4 cm (0.8–1.6 in) wide. The gills are decurrent
, and are quite closely spaced initially. The spore print
is creamy white, and the warty oval spores measure 8–12 x 7–9 μm
. The flesh
is white, and does not change colour on cutting. The flesh may smell faintly of fish or insects, and has a hot, bitter, tangy taste.
Similar whitish Lactarius species, such as L. piperatus
all exude milk from the gills, and the cut flesh.
zones, including Britain
, Europe
, Asia
. In North America Russula delica is rare, and is largely replaced by R. brevipes
, which is very similar, and is not on the British list.
A common mushroom, it appears in autumn in deciduous
and coniferous woods, and forests.
, but poor, having an unpleasant taste, leading some to classify it as inedible.
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...
that goes by the 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...
of milk-white brittlegill, and is a member of the 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...
genus, all of which are collectively known as brittlegills. It is mostly white, with brownish 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...
markings, and a short robust stem
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 is edible
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
, but poor in taste, and grows in mixed woods, in autumn. It can be confused with certain white 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...
species.
Taxonomy
First described by the Swedish mycologist Elias Magnus FriesElias Magnus Fries
-External links:*, Authors of fungal names, Mushroom, the Journal of Wild Mushrooming.*...
in 1838, its specific epithet delica is Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
for "weaned". Older names include Christian Hendrik Persoon
Christian Hendrik Persoon
Christiaan Hendrik Persoon was a mycologist who made additions to Linnaeus' mushroom taxonomy.-Early life:...
's Lactarius piperatus var. exsuccus.
This species has seen many taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
changes over the years. Many variants, and species have been separated from the true form, for various and myriad reasons. Notably Russula chloroides is given species status by some authorities, because of the narrow blue/green zone at the stem apex of some specimens. Gill spacing, and gill depth has also thrown many finds into doubt, in the past.
Mycologist John Burton Cleland
John Burton Cleland
Sir John Burton Cleland CBE was a renowned Australian naturalist, microbiologist, mycologist and ornithologist.-Early Life and education:...
collected a form he described in 1935 as R. delica from under eucalypt
Eucalypt
Eucalypts are woody plants belonging to three closely related genera:Eucalyptus, Corymbia and Angophora.In 1995 new evidence, largely genetic, indicated that some prominent Eucalyptus species were actually more closely related to Angophora than to the other eucalypts; they were split off into the...
s in the Mount Lofty Ranges
Mount Lofty Ranges
The Mount Lofty Ranges are the range of mountains just to the east of Adelaide in South Australia.-Location and description:The Mount Lofty Ranges stretch from the southernmost point of the Fleurieu Peninsula at Cape Jervis northwards for over before petering out north of Peterborough...
in South Australia, however, this was reclassified as a new species R. marangania in 1997 by Cheryl Grgurinovic.
Description
The basidiocarpBasidiocarp
In fungi, a basidiocarp, basidiome or basidioma , is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do not produce such structures...
s (fruiting bodies) of Russula delica seem loath to leave the soil, and are often found half buried. As a result, the caps
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...
often traps the surrounding leaf debris on their rough surfaces. The cap can be 16 cm (6.3 in) in diameter. It is white, usually tinged with ochre or brown, with an inrolled margin, which usually remains white. At first it is convex, but later flattens, and is often funnel shaped. The firm, white 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 short and stout, measuring 2–6 cm (0.8–2.4 in) high and 2–4 cm (0.8–1.6 in) wide. The gills are decurrent
Decurrent
Decurrent is a term used in botany and mycology to describe plant or fungal parts that extend downward.In botany, the term is most often applied to leaf blades that partly wrap or have wings around the stem or petiole and extend down along the stem...
, and are quite closely spaced initially. 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 creamy white, and the warty oval spores measure 8–12 x 7–9 μm
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
. The 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 does not change colour on cutting. The flesh may smell faintly of fish or insects, and has a hot, bitter, tangy taste.
Similar whitish Lactarius species, such as L. piperatus
Lactarius piperatus
Lactarius piperatus, commonly known as the peppery milk-cap is a semi-edible basidiomycete fungus of the genus Lactarius. Despite being edible, it is not recommended due to its poor taste, though can be used as seasoning when dried. The fruiting body is a creamy-white mushroom which is...
all exude milk from the gills, and the cut flesh.
Distribution and habitat
Russula delica is widespread in the northern temperateTemperate
In geography, temperate or tepid latitudes of the globe lie between the tropics and the polar circles. The changes in these regions between summer and winter are generally relatively moderate, rather than extreme hot or cold...
zones, including Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
, Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
. In North America Russula delica is rare, and is largely replaced by R. brevipes
Russula brevipes
Russula brevipes is a species of mushroom commonly known as the short-stemmed russula. It is edible, although its quality is improved once parasitised by the ascomycete fungus Hypomyces lactifluorum, transforming it into an edible known as a lobster mushroom.- Taxonomy :Russula brevipes was...
, which is very similar, and is not on the British list.
A common mushroom, it appears in autumn in deciduous
Deciduous
Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...
and coniferous woods, and forests.
Edibility
This mushroom is edibleEdible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
, but poor, having an unpleasant taste, leading some to classify it as inedible.