Boletus frostii, commonly known as Frost's bolete or the apple bolete, is an edible bolete mushroom 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 its cap. The fruit bodies may be recognized by their dark red sticky caps, the red pores, the network-like pattern of the stem, and the bluing reaction to bruising. Another characteristic of young, moist fruit bodies are the amber drops exuded on the pore surface. It is a mycorrhizal species, and the fruit bodies are typically found growing near hardwood trees, especially oak. Boletus frostii is distributed in the eastern United States from Maine to Georgia, Mexico, and Costa Rica. A subspecies, Boletus frostii ssp. floridanus, has been described and differs from the typical species in the color of the fruit body, and texture of the cap.