Cystolepiota bucknallii
Encyclopedia
Cystolepiota bucknallii is a species of basidiomycete
fungus
of the genus Cystolepiota
. Found throughout Europe, it is a rare fungus occurring in deciduous forests. The small fruiting bodies bear a distinctive smell of coal gas and appear in autumn on damp ground. It is not an edible mushroom.
of Cystolepiota bucknallii is a relatively small, thin-fleshed agaric
. The cap
is at first hemispherical and becomes convex with maturity. It bears a broad central umbo and reaches 5 cm in diameter. The cap cuticle
is white with a lilac or violet tinge. The gills are crowded and not attached to the stem. Their colour is cream to pale yellow. The stem
is comparatively long (up to 6 cm), slender and bare, tinged lilac or violet except for the uppermost section where it is pallid. Both cap and stem are covered with a mealy powder which is easily rubbed off. All parts are fragile. The flesh
is white, thin and does not bear a distinctive taste.
The spore mass
is coloured white. With the aid of a light microscope, the spore
s are seen ellipsoid, smooth and colourless. When Melzer's reagent
is applied, the spore walls barely stain; hence, the spores are weakly dextrinoid
. Their dimensions are 7.5–10 µm by 1-3.5 µm.
C. bucknallii has a characterisitcally pungent odour, reminiscent of coal gas
or sulphur. Indole
is present in this as well as in other similar-scented fungi: Tricholoma inamoenum, Tricholoma lascivum, Tricholoma sulphureum
and others.
While its edibility is not known, there exists speculation about possible toxicity.
, Belgium
, Switzerland
, Austria
, Germany
, Denmark
, Norway
, Sweden
and Russia
. It is a terrestrial decomposer
which occurs in deciduous forests with moist, calcareous
soils rich in nutrients and especially nitrogen
. Fruiting bodies appear in autumn
. Moreover, C. bucknallii is an uncommon or rare fungus whose population
s are found in communities
harbouring a diversity of other rare species. A population may serve as an indicator for rich, conservable
biotope
s.
Basidiomycota
Basidiomycota is one of two large phyla that, together with the Ascomycota, comprise the subkingdom Dikarya within the Kingdom Fungi...
fungus
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
of the genus Cystolepiota
Cystolepiota
Cystolepiota is a genus of fungi in the family Agaricaceae.-Species:A list of Cystolepiota species is presented below.* C. adulterina* C. bucknallii* C. constricta* C. fumosifolia* C. hetieri* C. luteohemisphaerica...
. Found throughout Europe, it is a rare fungus occurring in deciduous forests. The small fruiting bodies bear a distinctive smell of coal gas and appear in autumn on damp ground. It is not an edible mushroom.
Description
The fruiting bodyBasidiocarp
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...
of Cystolepiota bucknallii is a relatively small, thin-fleshed agaric
Agaric
An agaric is a type of fungal fruiting body characterized by the presence of a pileus that is clearly differentiated from the stipe , with lamellae on the underside of the pileus. "Agaric" can also refer to a basidiomycete species characterized by an agaric-type fruiting body...
. The 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...
is at first hemispherical and becomes convex with maturity. It bears a broad central umbo and reaches 5 cm in diameter. The cap 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 white with a lilac or violet tinge. The gills are crowded and not attached to the stem. Their colour is cream to pale yellow. The 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...
is comparatively long (up to 6 cm), slender and bare, tinged lilac or violet except for the uppermost section where it is pallid. Both cap and stem are covered with a mealy powder which is easily rubbed off. All parts are fragile. 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, thin and does not bear a distinctive taste.
The spore mass
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 coloured white. With the aid of a light microscope, the spore
Spore
In biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles of many bacteria, plants, algae, fungi and some protozoa. According to scientist Dr...
s are seen ellipsoid, smooth and colourless. When Melzer's reagent
Melzer's Reagent
Melzer's reagent is a chemical reagent used by mycologists to assist with the identification of fungi.-Composition:...
is applied, the spore walls barely stain; hence, the spores are weakly dextrinoid
Amyloid (mycology)
In mycology the term amyloid refers to a crude chemical test using iodine in either Melzer's reagent or Lugol's solution, to produce a black to blue-black positive reaction. It is called amyloid because starch gives a similar reaction, and that reaction for starch is also called an amyloid reaction...
. Their dimensions are 7.5–10 µm by 1-3.5 µm.
C. bucknallii has a characterisitcally pungent odour, reminiscent of coal gas
Coal gas
Coal gas is a flammable gaseous fuel made by the destructive distillation of coal containing a variety of calorific gases including hydrogen, carbon monoxide, methane and volatile hydrocarbons together with small quantities of non-calorific gases such as carbon dioxide and nitrogen...
or sulphur. Indole
Indole
Indole is an aromatic heterocyclic organic compound. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered nitrogen-containing pyrrole ring. Indole is a popular component of fragrances and the precursor to many pharmaceuticals. Compounds that contain an...
is present in this as well as in other similar-scented fungi: Tricholoma inamoenum, Tricholoma lascivum, Tricholoma sulphureum
Tricholoma sulphureum
Tricholoma sulphureum, also known as sulphur knight or gas agaric, is an inedible or mildly poisonous mushroom found in woodlands in Europe. It has a distinctive bright yellow colour and an unusual smell likened to coal gas...
and others.
While its edibility is not known, there exists speculation about possible toxicity.
Habitat
C. bucknallii has been recorded in various countries in central and northern Europe including FranceFrance
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, Belgium
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
, Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
, Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, Denmark
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...
, Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
, Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
and Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
. It is a terrestrial decomposer
Decomposer
Decomposers are organisms that break down dead or decaying organisms, and in doing so carry out the natural process of decomposition. Like herbivores and predators, decomposers are heterotrophic, meaning that they use organic substrates to get their energy, carbon and nutrients for growth and...
which occurs in deciduous forests with moist, calcareous
Calcareous
Calcareous is an adjective meaning mostly or partly composed of calcium carbonate, in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines.-In zoology:...
soils rich in nutrients and especially nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
. Fruiting bodies appear in autumn
Autumn
Autumn is one of the four temperate seasons. Autumn marks the transition from summer into winter usually in September or March when the arrival of night becomes noticeably earlier....
. Moreover, C. bucknallii is an uncommon or rare fungus whose population
Population
A population is all the organisms that both belong to the same group or species and live in the same geographical area. The area that is used to define a sexual population is such that inter-breeding is possible between any pair within the area and more probable than cross-breeding with individuals...
s are found in communities
Community (ecology)
In ecology, a community is an assemblage of two or more populations of different species occupying the same geographical area. The term community has a variety of uses...
harbouring a diversity of other rare species. A population may serve as an indicator for rich, conservable
Habitat conservation
Habitat conservation is a land management practice that seeks to conserve, protect and restore, habitat areas for wild plants and animals, especially conservation reliant species, and prevent their extinction, fragmentation or reduction in range...
biotope
Biotope
Biotope is an area of uniform environmental conditions providing a living place for a specific assemblage of plants and animals. Biotope is almost synonymous with the term habitat, but while the subject of a habitat is a species or a population, the subject of a biotope is a biological community.It...
s.