''Leucocoprinus cygneus'' is a species of

mushroom A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. ''Toadstool'' generally denotes one poisonous to humans. The standard for the name "mushroom" is t ...

producing

fungus A fungus ( : fungi or funguses) is any member of the 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, separately from th ...

in the family

Agaricaceae The Agaricaceae are a family of basidiomycete fungi and include the genus ''Agaricus'', as well as basidiomycetes previously classified in the families Tulostomataceae, Lepiotaceae, and Lycoperdaceae. Taxonomy The family Agaricaceae was publishe ...

Taxonomy

It was first described in 1940 by the Danish mycologist

Jakob Emanuel Lange Jakob Emanuel Lange (2 April 1864 – 27 December 1941), was a Danish mycologist who studied the systematics of gilled mushrooms. His best-known work is ''Flora Agaricina Danica'', a five-volume plate work on the Agaricales of Denmark. He was als ...

who classified it as ''Lepiota cygnea'' until 1952 when it was classified as ''Pseudobaeospora cygnea'' by the French mycologist

Marcel Locquin Marcel Locquin, born May 6, 1922, in Lyon, France, died March 18, 2009, was a French mycologist. Locquin rose to eminence in the field of mycology over several years of work with a number of Nobel Prize winners. He himself has won numerous awar ...

. In 1978 the Belgian mycologist

Paul Heinemann Paul Heinemann (February 16, 1916 – June 18, 1996) was a Belgian botanist and mycologist. Heinemann specialized in African mycology. In his long career, he published 435 names, including 2 families, 6 genera, 346 species, and 40 varieties. His co ...

created the new genus ''Sericeomyces'' in an attempt to better arrange the species which are now recognised as belonging to the ''

Lepiota ''Lepiota'' is a genus of gilled mushrooms in the family Agaricaceae. All ''Lepiota'' species are ground-dwelling saprotrophs with a preference for rich, calcareous soils. Basidiocarps (fruit bodies) are agaricoid with whitish spores, typically ...

'', ''

Leucoagaricus ''Leucoagaricus'' is a genus of fungi in the family Agaricaceae. Several fungus-growing ants cultivate multiple species for food. The genus contains approximately 90 species. Taxonomy This group of mushrooms was first defined as a subgenus of ' ...

'' and ''

Leucocoprinus ''Leucocoprinus'' is a genus of fungi in the family Agaricaceae. Its best-known member is the distinctive yellow mushroom '' Leucocoprinus birnbaumii'', which is found in plant pots and greenhouses worldwide. The type species is '' Leucocoprinus ...

'' genera. He reclassified this species as ''Sericeomyces cygneus'' but noted that placing it in this newly created genus was questionable. This proposed placement turned out to be short lived as it was also in 1978 that Austrian mycologist

Meinhard Michael Moser Meinhard Michael Moser (13 March 192430 September 2002) was an Austrian mycologist. His work principally concerned the taxonomy, chemistry, and toxicity of the gilled mushrooms (Agaricales), especially those of the genus ''Cortinarius'', and th ...

classified it as ''Cystolepiota cygnea'' and the French mycologist

Marcel Bon Marcel Bon (17 March 1925 – 11 May 2014)http://fmbds.org/wp-content/uploads/2014/06/CAFAM-2014-CR-complet.pdf was one of France's best known field mycologists. He was born in Picardy in 1925 and came to mycology through general botany, and ph ...

classified it as ''Leucocoprinus cygneus'', which was ultimately the classification which was adopted.

Description

''Leucocoprinus cygneus'' is a small dapperling mushroom with thin white flesh and a white, powdery cap. Cap: 1.5–2 cm. Campanulate and expanding as it matures. Pure white and slightly silky. Stem: 3 cm tall by 2mm in thickness. Hollow and smooth with a ring. Gills: White, narrow, crowded and free. Spores: Ellipsoid with a tiny germ pore. Dextrinoid. 6.5 x 3.5 μm.

Etymology

The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''cygneus'' (originally ''cygnea'') derives from the Latin for ''cygnus'' meaning swan. This is in reference to the 'swan-like' colour of the cap.

Habitat and distribution

This species is rarely recorded. In the UK only two collections of ''L cygneus'' have been documented with one specimen in Kew's collection which was found in West Norfolk and a second in a collection in Edinburgh from a specimen found in South Devon. The first was found growing inside a hollow tree trunk whilst the second was found on damp ground. It is now speculated that the specimen found on the rotting wood may be '' Leucocoprinus griseofloccosus'' instead.

Similar species

* '' Leucocoprinus griseofloccosus''

References

{{Taxonbar, from=Q10560184 Agaricaceae Leucocoprinus Fungi described in 1940 Taxa named by Marcel Locquin