ABSTRACTXeromphalina nubium sp. nov.is described from two table mountains, Cerro de la Neblina and ChimantáMassif, surrounded by lowland tropical forests in the Guayanan highlands of Venezuela. The representative of the latter location had been misdetermined asXeromphalina helbergeriSinger. The range ofX. helbergeriis extended to Cuba, Guatemala, and Jamaica from Argentina and Colombia. This species and allies are compared toX. nubium.