Boletus aereus    Bull.:Fr. 

common name(s) : Bronze Bolete, Dark Cep, Negro-head Bolete, Tanned Cep 

New classification: Basidiomycota/Agaricomycotina/Agaricomycetes/Agaricomycetidae/Boletales/Boletaceae  
Former classification: Basidiomycota/Homobasidiomycetes/Agaricomycetideae/Boletales/Boletaceae/Boletoideae [ section:Edules ]  

synonyms: Tubiporus aereus 
(unconfirmed synonyms: Boletus edulis-aereus)  

edibility : edible, good

photo gallery of  Boletus aereus
photo gallery of  Boletus aereus potential confusions with  Boletus aereus toxicity of Boletus aereus genus Boletus  

The cap is dark brown to black, without any shade of red, becoming marbled (sepia-brown stains on an ochre background) with time, thick, fleshy, massive, hemispherical then convex to more or less flattened. The cap surface is smooth or finely velvety, dry, cracked, giving it a rough structure. The cap margin is often paler.

The stem is thick, full, short, egg-shaped at first then club-shaped, and eventually cylindrical, always swollen towards base. It is red-ochre to tawny brown, covered with a large network of thin lines, brown towards the stem's apex, clay-brown towards its middle, more reddish towards base, darkening with age..

The flesh is thick, compact and firm, white even under cap surface, its colour unchanging when exposed to air; its taste is pleasant; the odour is pleasant;

The tubes are thin, easily separated, rather long (15-25mm), whitish then greenish-yellow to olive-brown, with their unchanging when bruised.

The pores are narrow, rounded, regular, dull yellow then greenish-yellow to olive-brown (same colour as tubes), their colour unchanging when pressed. The spore print is olive brown.

It grows in warm areas and southern parts of Europe, in well ventilated places of deciduous woods (edges, clearings, pathsides) but also in bushes, thickets of open woodlands, with common oak most of the time, also with beech, hornbeam, chestnut.

The fruiting period takes place from May to November.
Dimensions: width of cap approximately 14 cm (between 4 and 35 cm)
  height of stem approximately 10 cm (between 5 and 20 cm)
  thickness of stem (at largest section) approximately 45 mm (between 11 and 80 mm)
  spores : 12-16 x 4-5,5 microns, spindle-shaped

Chemical tests : flesh becoming pale red when in contact with ammonia.

Distinctive features : brown stem, with dense white then brownish network; pores round and very narrow; very dark brown cap (almost black, without any red shades), velvety; earthy odour

Boletus aereus is quite rare and scattered in the forest of Rambouillet, and is infrequent, more generally speaking .
here should be the distribution map of Boletus aereus in the forest of Rambouillet
Above : distribution map of Boletus aereus in the forest of Rambouillet

page updated on 14/01/18