Lomaantha phragmitis sp.nov.is described and illustrated from a specimen collected on dead culms of Phragmites communis in southern China.The fungus differs from other described Lomaantha species in its conidiophores, conidiogenous cells and conidial appendages.Conidial morphology and presence or absence of percurrent proliferation of eonidiogenous cells are the main characters distinguishing species within this genus.We provided a key and synoptic table of morphological characters of all three Lomaantha species.