''Phlegmacium glaucopus'' is a species of fungus in the family Cortinariaceae. It is commonly known as the blue-foot webcap.

Taxonomy

The species was first described as ''Agaricus glaucopus'' by Jacob Christian Schäffer in 1774. It was reclassified as ''Cortinarius glaucopus'' in 1821 by the British mycologist Samuel Frederick Gray. However the fully taxonomic history of this species is complicated by numerous proposed variants and forms. Within the genus '' Cortinarius'', it was classified in the subgenus ''Phlegmacium'' and section ''Glaucopodes''. A 2014 genetic study confirmed it was synonymous with ''C. glaucopoides'' and that ''C. subrubrovelatus'' was a distinct species. In 2022 a genomic study was carried out which radically reshaped the family Cortinariaceae resulting in many ''Cortinarius'' species being transferred to new or existing genera. ''C. glaucopus, C. glaucopoides'' and ''C. glaucopoides'' were among the species transferred to the ''

Phlegmacium ''Phlegmacium'' is a genus of fungi in the family Cortinariaceae. Taxonomy The genus was created in 1877 by the German mycologist Friedrich Otto Wünsche based on the earlier 1821 classification of the ''Agaricus'' tribe ''Phlegmacium'' by t ...

'' genus. Common names in other languages include ''Schwachknolliger Klumpfuss'' (German), ''Cortinaire à pied glauque'' (French) and ''Szálaskalapú pókhálósgomba'' (Hungarian).

Description

The fruit bodies of this fungus have convex caps across and ochre or tawny in colour with prominent darker brown fibres. Like other members of the genus, young mushrooms are covered in a web-like veil (cortina) from the cap margin to the stipe. The bulbous stipe is 4–10 cm tall and 1–3 cm wide, pale lilac-blue initially with lower parts fading to yellow-white. The flesh is yellow-white with a blue hue in the upper stipe. The lilac-blue gills are adnate or free, and become brown as the spores mature. The smell, if present, is slightly mealy. The spore print is red-brown and the spores measure 6.5–8.5 by 4.5–5

µm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

. Fruit bodies appear from August onwards into autumn in deciduous and coniferous forests, often in profuse numbers. It can be found in fairy rings. ''Phlegmacium glaucopus'' is found in Western North America (both the United States and Canada), and is common in the Rocky Mountains. It is rare east of the

Great Plains The Great Plains (french: Grandes Plaines), sometimes simply "the Plains", is a broad expanse of flatland in North America. It is located west of the Mississippi River and east of the Rocky Mountains, much of it covered in prairie, steppe, an ...

; it is rare in the British Isles. ''P. glaucopus'' forms ectomycorrhizae that are unusually hydrophobic (water-repellent) compared with other fungi, which has led to interest in decoding its genome. DNA studies indicate it may decompose toxic polycyclic aromatic compounds in the soil with specially adapted oxidizing enzymes.

Habitat and distribution

It is native to Europe and North America.

Similar species

Similar species include ''C. caerulescens'', ''C. pansa'', ''C. sodagnitus'', and '' C. subfoetens''.

Edibility

The flesh is mild tasting, and not highly regarded. It is considered inedible, and because it closely resembles many other species, including those that are deadly poisonous, it should definitely not be eaten. In Tlaxcala, Mexico, it is collected in June and sold in the market.

References