Butyriboletus regius (formerly Boletus regius), commonly known as the royal bolete or red-capped butter bolete, is a basidiomycete species of fungus in the genus Butyriboletus. It has a pink cap, yellow flesh, and a reticulate pattern on the stem.

The mushroom is found in North America, Europe, and China. North America specimens stain blue when exposed to air, but European specimens do not, or only stain weakly. Both are edible and considered choice.

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