Gyroporus castaneus    (Bull.:Fr.) Quél. 

common name(s) : Chestnut Bolete 

New classification: Basidiomycota/Agaricomycotina/Agaricomycetes/Agaricomycetidae/Boletales/Gyroporaceae  
Former classification: Basidiomycota/Homobasidiomycetes/Agaricomycetideae/Boletales/Boletaceae/Gyrodontoideae  

synonyms: Boletus castaneus 

edibility : discard

photo gallery of  Gyroporus castaneus
photo gallery of  Gyroporus castaneus potential confusions with  Gyroporus castaneus toxicity of Gyroporus castaneus genus Gyroporus  

The cap is red-chestnut, tawny brown to copper-brown, then more yellowish and uniform in colour, fleshy, firm, hemispherical, then convex to flattened, more or less irregular, sometimes depressed at the centre. The cap surface is finely downy, dry, smooth in some places, matt, sometimes cracked with age. The cap margin is wavy, thin.

The stem is cylindrical or with a swollen base, stuffed then hollow, easily separated from the cap. It is felty then smooth, with a hard external shell becoming brittle (like a brittlegill) when it becomes hollow with age. It is concolorous to the cap or paler (especially in the top)..

The flesh is firm, brittle, white then cream, often unchanging, but reddening sometimes very lightly when in contact with air; its taste is faint, mild, hazelnut; the odour is weak, mushroomy or nutty;

The tubes are practically free, thin, very short. They are white then lemon yellow, not turning blue when touched.

The pores are very small, round, white then lemon yellow tinted with ochre, not turning blue when pressed. The spore print is yellowish.

It grows in (dense) broad-leaved forests, solitary or in small troops, less frequently under conifers or in parks, on a rather acid, sandy soil, with oak essentially, also with beech, chestnut.

The fruiting period takes place from June to November.
Dimensions: width of cap approximately 7 cm (between 3 and 12 cm)
  height of stem approximately 7 cm (between 3.5 and 10 cm)
  thickness of stem (at largest section) approximately 20 mm (between 10 and 30 mm)
  spores : 7-12 x 4,5-6,5 microns, ellipsoid, smooth

Chemical tests : no reaction of flesh to ammonia.

Distinctive features : Chestnut brown cap, contrasting with the white (eventually yellowish) pores; tough stem becoming hollow with age; flesh and pores not turning blue when pressed or exposed to air

Gyroporus castaneus is quite rare and localised in the forest of Rambouillet, and is infrequent, more generally speaking .
here should be the distribution map of Gyroporus castaneus in the forest of Rambouillet
Above : distribution map of Gyroporus castaneus in the forest of Rambouillet



page updated on 14/01/18