Gyroporus cyanescens    (Bull.:Fr.) Quél. 

common name(s) : Cornflower Bolete, Blueing Bolete 

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

synonyms: Boletus cyanescens 
(unconfirmed synonyms: Gyroporus cyanescens-violaceotinctus)  

edibility : edible, good

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

The cap is whitish, greenish-grey to yellowish, fleshy, thick, hemispherical, then convex to flattened, more or less irregular, often depressed at the centre. The cap surface is fluffy, felty (rough to the touch) and very dry. The cap margin is inrolled a long time, often fringed.

The stem is thick, easily separated from stem, stout or swollen, sturdy although fragile because of its spongy nature, later hollow or stuffed with a cottony substance when mature. It sometimes cracks to make ring-like zones. It is whitish at the top, and concolorous to cap (cream yellow) below. It is smooth just under the cap, and fluffy in its lower part, below a ring-like zone not very clear..

The flesh is thick, firm, brittle, white to cream, turning instantly to indigo blue when in contact with air (especially in damp weather) before fading to pale grey-white; its taste is mild or not distinctive; the odour is weak, pleasant or not distinctive;

The tubes are almost free, thin, easily removed from cap, long (15-25mm), white then pale yellowish, with a tinge of yellow or greenish with age, turning blue at the slightest touch.

The pores are small, round, white then cream, eventually greenish yellow, turning strongly blue when pressed. The spore print is pale greenish yellow.

It grows in dry deciduous and coniferous forests, sometimes in heath, privileging warm places protected from wind. It comes in small groups or solitary, on a rather acid, but also sandy and poor in litter soil, with beech, birch, oak, chestnut, pine, spruce, fir.

The fruiting period takes place from July to December.
Dimensions: width of cap approximately 9 cm (between 3.5 and 18 cm)
  height of stem approximately 9 cm (between 4 and 15 cm)
  thickness of stem (at largest section) approximately 35 mm (between 15 and 85 mm)
  spores : 10-18 x 3,5-5,5 microns, spindle-shaped

Chemical tests : no reaction to iodine or ammonia.

Distinctive features : whitish to cream-ochraceous (sometimes even yellow) cap; white pores, turning eventually greenish cream; flesh and pores turning intensely blue when pressed or exposed to air; hollow stem when mature, sometimes with ring-like zone;

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



page updated on 14/01/18