Caloboletus frustosus is a bolete fungus native to North America.

Until 2014, it was known as Boletus frustosus.

Recent changes[2][3] in the phylogenetic framework of the family Boletaceae prompted the transfer of this species, along with several other related boletes, including Caloboletus calopus, to the genus Caloboletus.

[4] It was first described scientifically in 1941 by mycologists Wally Snell and Esther Dick.

This Boletales-related article is a stub.