The anamorphic taxon Anacacumisporium appendiculatum gen. et sp. nov. is described and illustrated from fallen branches of decaying wood in Hainan, China. Anacacumisporium is characterized by pigmented, transversely septate, appendaged conidia and conidiophores that are brown, macronematous, mononematous and that bear one (or more ) integrated phialide at the tip. Complete sequences of internal transcribed spacer (ITS) and partial sequences of nuc 28S rDNA (28S) genes are provided. The new fungus is compared with morphologically similar genera of hyphomycetes. Phylogenetic analyses revealed its placement in the Chaetosphaeriaceae. A key to the novel genus and morphologically similar genera is given.