The Boletaceae are a family of mushroom-forming fungi, primarily characterised by small pores on the spore-bearing hymenial surface, instead of gills as are found in most agarics. Nearly as widely distributed as the agarics, the family is renowned for hosting some prime edible species highly sought after by mushroom hunters worldwide, such as the cep or king bolete . A number of rare or threatened species are also present in the family, that have become the focus of increasing conservation concerns. As a whole, the typical members of the family are commonly known as boletes.
Exsudoporus frostii, commonly known as Frost's bolete or the apple bolete, is a bolete fungus first described scientifically in 1874. A member of the family Boletaceae, the mushrooms produced by the fungus have tubes and pores instead of gills on the underside of their caps. Exsudoporus frostii is distributed in the eastern United States from Maine to Georgia, and in the southwest from Arizona extending south to Mexico and Costa Rica. A mycorrhizal species, its fruit bodies are typically found growing near hardwood trees, especially oak.
Butyriboletus appendiculatus is an edible pored mushroom that grows under oaks and other broad leaved trees such as beech. It is commonly known as the butter bolete. It often grows in large colonies beneath the oak trees, and is frequently found cohabiting with old oaks in ancient woodland. It is relatively rare in Britain. Its stipe and pores are often bright yellow and its flesh stains bright blue when cut or bruised.
Rubroboletus rhodoxanthus is a species of bolete in the family Boletaceae, native to Europe. Previously known as Boletus rhodoxanthus, it was transferred in 2014 to the newly erected genus Rubroboletus, based on DNA data.
Butyriboletus regius, commonly known as the royal bolete or red-capped butter bolete, is a basidiomycete fungus of the genus Boletus found in China and Europe. B. regius has a pink cap, yellow flesh, and a reticulate pattern on the stem. Harry D. Thiers described a similar mushroom from California as B. regius, though it is not the same species. B. regius in Europe does not stain when exposed to air, or stains weakly, but the California species stains blue. Both European and California species are considered choice edibles.
Butyriboletus roseopurpureus is a species of fungus in the family Boletaceae. Found in eastern North America, it was officially described in 2000 as a species of Boletus, and transferred to the genus Butyriboletus in 2015.
Butyriboletus peckii is a fungus of the genus Butyriboletus native to eastern North America. It was first described by Charles Christopher Frost in 1878. Until 2014, it was known as Boletus peckii. Recent changes in the phylogenetic framework of the Boletaceae prompted the transfer of this species, along with several other related boletes, including Caloboletus calopus, to the genus Caloboletus. In 2015, Kuan Zhao and colleagues published analysis that demonstrated that the bolete belongs to Butyriboletus, closely related to Butyriboletus pulchriceps.
Butyriboletus querciregius is a pored mushroom in the genus Butyriboletus. Found in California, where it grows in a mycorrhizal association with coast live oak, it was described as new to science in 2014.
Butyriboletus roseoflavus is a pored mushroom in the genus Butyriboletus found in Asia. It was originally described in 2013 as a species of Boletus, but was transferred the following year to the newly created genus Butyriboletus.
Butyriboletus sanicibus is a pored mushroom in the genus Butyriboletus. Found in China where it grows in association with Yunnan pine, it was described as a new species in 2014.
Butyriboletus subappendiculatus is a pored mushroom in the family Boletaceae. This European species was originally described as a species of Boletus in 1979, but later transferred to Butyriboletus in 2014. It is considered endangered in the Czech Republic.
Butyriboletus yicibus is a pored mushroom in the genus Butyriboletus. Found Yunnan, China, where it grows in association with Yunnan pine, it was described as a new species in 2014.
Butyriboletus abieticola is a pored mushroom in the family Boletaceae. It was originally described in 1975 by mycologist Harry Delbert Thiers as a species of Boletus, but transferred in 2014 to the newly created genus Butyriboletus.
Butyriboletus brunneus is a pored mushroom in the family Boletaceae. This North American species was originally described by Charles Horton Peck in 1890 as a variety of Boletus speciosus.
Butyriboletus fuscoroseus is a pored mushroom in the family Boletaceae. It was formerly considered a species of Boletus, but in 2014 was transferred to the newly created genus Butyriboletus. Boletus pseudoregius, a European taxon originally described as a subspecies of Boletus appendiculatus in 1927, is a synonym. B. fuscoroseus is considered critically endangered in the Czech Republic.
Butyriboletus fechtneri is a basidiomycete fungus in the family Boletaceae. It was formerly regarded as a species of Boletus, but in 2014 was transferred to the newly erected genus Butyriboletus, after molecular data revealed that it is a member of the "Regius" clade, quite distant from the core clade of B. edulis and closely allied species.
Butyriboletus persolidus is a pored mushroom in the family Boletaceae. Found in California, where it grows in a mycorrhizal association with coast live oak, it was described as new to science in 2014.
Butyriboletus primiregius is a pored mushroom in the family Boletaceae. Found in California, where it grows in a mycorrhizal association with fir, it was described as new to science in 2014.
Caloboletus is a fungal genus in the family Boletaceae. It was circumscribed by Italian mycologist Alfredo Vizzini with Caloboletus calopus as the type species. The erection of Caloboletus follows recent molecular studies that outlined a new phylogenetic framework for the Boletaceae. Boletus peckii was also transferred to this genus by Vizzini, but was subsequently moved to the genus Butyriboletus based on molecular evidence. The generic name Caloboletus, derived from the Greek calos "nice", refers to the attractive red coloring of the stipe.
Exsudoporus is a genus of fungi in the family Boletaceae. It was circumscribed in 2014 by Alfredo Vizzini and colleagues, following a number of molecular studies that outlined a new phylogenetic framework for Boletaceae and revealed the genus Boletus in its traditional circumscription to be polyphyletic. However, due to lack of sufficient sequences, Wu and colleagues (2016) were reluctant to accept the newly proposed genus and considered it a synonym of Butyriboletus. Following additional phylogenetic sequencing and morphological analyses, Exsudoporus was clearly resolved as a monophyletic, homogenous and independent genus that is sister to Butyriboletus.
