Tylopilus rubrobrunneus

Tylopilus rubrobrunneus, commonly known as the reddish brown bitter bolete, is a bolete fungus in the family Boletaceae. It was first described scientifically in 1967 by Samuel J. Mazzer and Alexander H. Smith from collections made in Michigan. It is found in the United States; the bolete was reported from a Mexican beech (Fagus mexicana) forest in Hidalgo, Mexico in 2010.

The species is inedible and very bitter in taste.