abstract
Three new and one previously described species of Clavulina (Clavulinaceae, Cantharel-
lales, Basidiomycota) are reported from the central Guiana Shield region from tropical rain-
forests dominated by ectomycorrhizal trees of the leguminous genus Dicymbe (Fabaceae
subfam. Caesalpinioideae). We provide morphological, DNA sequence, habitat, and fruiting
occurrence data for each species. The new species conform to a generic concept of Clavu-
lina that includes coralloid, branched basidiomata with amphigenous hymenia, basidia
with two or 24 incurved sterigmata and postpartal septa present or absent, and smooth,
hyaline, guttulate basidiospores. Placements of the new species in Clavulina were corrobo-
rated with DNA sequence data from the internal transcribed spacer and large subunit of
the nuclear ribosomal repeat, and their infrageneric relationships were examined with
phylogenetic analyses based on DNA from the region coding for the second largest subunit
of DNA-dependent RNA polymerase II (rpb2). To facilitate future studies of the genus in the
neotropics, a key is provided for all Clavulina species described from the lowland
neotropics.