Two new African siblings of Pulveroboletus ravenelii (Boletaceae)

This paper sorts out the taxonomy of species affiliated with Pulveroboletusravenelii in the Guineo-soudanian and Zambezian woodlands of Africa. Morphological and genetic characters of African Pulveroboletus collections were studied and compared to those of North American and Asian species. A phylogenetic analysis showed that the African specimens form a subclade, sister to the Asian and American taxa. Although clamp connections have previously never been reported from Pulveroboletus , all specimens of the African subclade show very small clamp connections. Two new African species, Pulveroboletusafricanus sp. nov. and P.sokponianus sp. nov. , are described and illustrated. Comments concerning morphology and identification, as well as distribution and ecology, are given for both species.