Xerocomus porosporus    (Imler ex Bon & G. Moreno) Contu 

common name(s) : Sepia Bolete 

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

synonyms: Xerocomellus porosporus, Boletus porosporus 

edibility : discard

photo gallery of  Xerocomus porosporus
photo gallery of  Xerocomus porosporus potential confusions with  Xerocomus porosporus toxicity of Xerocomus porosporus genus Xerocomus  

The cap is tawny-yellow to dark olive-brown or sepia, generally without any reddish shades, fleshy, convex then expanded. The cap surface is matt, dry and never viscid, downy at first then smooth, almost always cracking into large patches when drying, showing a yellow skin underneath without any reddish tinge.

The stem is chrome yellow at the apex, washed with brown longitudinally and darkening at the base or when bruised, and generally without any red tinge, but sometimes with a blood-red zone. It is cylindrical to tapering towards the base..

The flesh is soft, pale, whitish to lemon yellow in the cap, chrome yellow at stem's apex, brown-red at its base; its taste is mild, faint; the odour is faint or indistinct;

The tubes are adnate to decurrent through a tooth, short (8-14mm). They are pale lemon yellow then olivaceous yellow, turning slightly blue when exposed to air.

The pores are rather large, angular, pale lemon yellow then olive green to dark brown in the end. They become slightly blue-green when pressed. The spore print is olive-green to walnut-brown.

It grows in broad-leaved and coniferous woods, favouring oak.

The fruiting period takes place from June to November.
Dimensions: width of cap approximately 5 cm (between 2 and 8 cm)
  height of stem approximately 8 cm (between 4 and 10 cm)
  thickness of stem (at largest section) approximately 25 mm (between 20 and 30 mm)
  spores : 12-16 x 4-6 microns, sub-fusiform, thick-walled and without droplet, with disctinctive truncate spores on mature spores, sole feature of this kind for an European bolete

Distinctive features : dull brown cap with olivaceous shades, soon cracked, without showing red underneath or in bruises; pale lemon yellow stem at the apex, brown and blackening at the base, with sometimes a blood-red zone but usually without; pores turning blue when pressed (micro: mature spores with truncate pore)

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



page updated on 14/01/18