ABSTRACT: Tylopilus pakaraimensis sp. nov. (Boletaceae) is described as new to science. This bolete species was collected from rainforests dominated by ectomycorrhizal Dicymbe spp. (Caesalpiniaceae) in the Pakaraima Mountains of western Guyana, South America. Tylopilus pakaraimensis is assigned to the neotropical Tylopilus section Potamogetones based on the unusual spore characteristics and macrochemical reactions. A key is provided for the taxa of Tylopilus section Potamogetones.

KEYWORDS: Boletaceae, neotropics, basidiomycetes, biodiversity, taxonomy

NOMENCLATURAL NOVELTIES:
Tylopilus pakaraimensis T.W.Henkel, p. 106