Most class 3 fungal endophytes (sensu Rodriguez et al. 2009) belong to the Ascomycota; members of Basidiomycota are much more infrequently isolated. Endophytic Basidiomycota may be more common in foliage than currently indicated, but biases in identification methods (e.g., primer bias, culturing vs. environmental sequencing) may mask their true diversity and abundance as endophytes.