 Suillellus luridus ( formerly Boletus luridus ) , commonly known as the lurid bolete , is a fungus of the bolete family , found in deciduous woodlands on chalky soils in Asia , Europe , and eastern North America . Fruit bodies appear in summer and autumn and may be abundant . It is a solid bolete with an olive @-@ brown cap up to 15 cm ( 6 in ) in diameter and a white stem . The cap is usually flat , but may be slightly concave when young . The pores are initially white , but turn brown with age . The stem is white and sometimes has a purple tinge . The lurid bo