Abstract
A large number of ascomycetes have been described from the palm Calamus. In this study, we report on Neodeightonia species (Botryosphaeriaceae) from the rachides of Calamus spp. collected in Phang-Nga Province, Thailand. Morphological characters were studied and with support from phylogenetic analyses of combined ITS, LSU, SSU and TEF1-alpha sequence data we introduce two new species Neodeightonia rattanica, and N rattanicola The new species are introduced with descriptions and illustrations and compared with other Neodeightonia species.