Suillus serotinus is a species of bolete fungus found in eastern North America.
Originally described as a species of Boletus by American botanist Charles Christopher Frost in 1874,[2] it was transferred to Suillus in 1996.
[3] The bolete has a dark red brown and sticky cap up to 12 cm (4.7 in) in diameter.
Mushroom flesh slowly stains bluish after injury, later becoming purplish gray then finally reddish brown.
The fungus grows in a mycorrhizal association with larch and fruits on the ground scattered or in groups.