Agaricus urinascens    (F.H. Møller) Schaeff. 

common name(s) : Macro Mushroom, Albert's Mushroom 

New classification: Basidiomycota/Agaricomycotina/Agaricomycetes/Agaricomycetidae/Agaricales/Agaricaceae  
Former classification: Basidiomycota/Homobasidiomycetes/Agaricomycetideae/Agaricales/Agaricaceae/Agariceae [ section:Arvenses sub-section:Arvenses]  

synonyms: Agaricus macrosporus, Psalliota arvensis-macrospora, Agaricus urinascens-urinascens, Psalliota urinascens, Psalliota macrospora, Agaricus albertii 
(unconfirmed synonyms: Agaricus villaticus)  

edibility : edible, good

potential confusions with  Agaricus urinascens toxicity of Agaricus urinascens genus Agaricus  

The cap is white, fleshy, becoming ochre with age. The cap surface is covered with radial fibrils or very fine ochre-brown scales, not viscid nor sticky.

The flesh is white, turning pink when exposed to air; its taste is mild, of aniseed or almonds; the odour is mild, also of aniseed or almonds (young) or ammonia (old); its texture is fibrous.

The gills are free, crowded . The spore print is brown. This species is saprophytic. It grows on the ground, on a rather calcareous soil.

The fruiting period takes place from May to November.
Dimensions: width of cap approximately 19 cm (between 8 and 50 cm)
  height of stem approximately 10 cm (between 5 and 20 cm)
  thickness of stem (at largest section) approximately 35 mm (between 20 and 80 mm)

Chemical tests : variable reaction to Schaeffer's test.

Distinctive features : white cap, with very large size; large spores; cap turning yellow with age; flesh turning weakly ping when exposed to air; stem with membranous ring, tapering towards both ends

Agaricus urinascens is still unreported so far in the forest of Rambouillet, and is occasional, more generally speaking .



page updated on 14/01/18