Two new species of Butyriboletus from China

Butyriboletus brunneoides sp. nov. and Bu. sinoregius sp. nov. are described from Shanxi Province of China based on morphology and molecular work. Butyriboletus brunneoides differs from Bu. brunneus by the small to medium basidiome, smooth pileus, and a thin stipe that develops reddish stains near the base. Butyriboletus sinoregius differs from the European B. regius by a basidiome bluing when bruised and a pileus covered with fine tomentum. Phylogenetic analyses based on ITS, nrLSU, tef1-α and rpb2 sequences support the taxonomic position of the two new species. Illustrated macro- and micro-descriptions are provided along with a key to the Butyriboletus species from China.