Exsudoporus floridanus is a species of edible bolete mushroom in the family Boletaceae. In 1945, American mycologist Rolf Singer described a species he found in Florida during his 1942–3 tenure of a Guggenheim Memorial Fellowship. He originally described it as a subspecies of the eastern North American species Boletus frostii, but later considered it worthy of distinct species status in a 1947 publication. Based on morphological and phylogenetic data, Vizzini and colleagues transferred this species to a newly described genus Exsudoporus in 2014.
Due to lack of sufficient sequences, Wu et al. (2016) were reluctant to accept Exsudoporus and considered it a synonym of Butyriboletus, so they proposed a new combination Butyriboletus floridanus. However, following phylogenetic and morphological analyses clearly resolved Exsudoporus as a monophyletic, homogenous and independent genus that is sister to Butyriboletus.
Exsudoporus floridanus
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.
Exsudoporus frostii
View of the hymenium
Young fruit bodies may secrete an amber liquid.
Poisonous Boletus flammans is similar in appearance.