Caloboletus firmus is a bolete fungus native to North America. Until 2014, it was known as Boletus firmus. Recent changes[1][2] 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.[3] It was first described scientifically in 1874 by American botanist Charles Christopher Frost from specimens collected in New England.[4]
^Nuhn ME, Binder M, Taylor AF, Halling RE, Hibbett DS (2013). "Phylogenetic overview of the Boletineae". Fungal Biology. 117 (7–8): 479–511. doi:10.1016/j.funbio.2013.04.008. PMID23931115.
^Wu G, Feng B, Xu J, Zhu XT, Li YC, Zeng NK, Hosen MI, Yang ZL (2014). "Molecular phylogenetic analyses redefine seven major clades and reveal 22 new generic clades in the fungal family Boletaceae". Fungal Diversity. 69 (1): 93–115. doi:10.1007/s13225-014-0283-8. S2CID15652037.
