The Boletaceae are a family of mushroom-forming fungi, primarily characterised by small pores on the spore-bearing hymenial surface (at the underside of the mushroom), 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 (Boletus edulis). 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. Boletes are a group of mushrooms reasonably safe for human consumption, as none of them are known to be deadly to adults. Edible bolete species are especially suitable for novice collectors, since they pose little danger of being confused with deadly poisonous mushrooms, such as deadly Amanita species which bear gills instead of pores in their hymenial surface. Some boletes are toxic and may cause gastrointestinal poisoning if consumed, but these are unlikely to be confused with popular edible species in the family. The family has been the subject of extensive systematic revisions in recent years, as some of the early established genera (particularly Boletus, Leccinum and Xerocomus), have revealed to be highly polyphyletic, and the original number of genera within the family had been underestimated. As a result, several new species and genera have been described from Asia, Europe and North America, while many existing species have been transferred to different genera, in concordance with phylogenetic results. Source: Wikipedia (en)