Melanothrix nymphaliaria is a moth in the Eupterotidae family. It was described by Walker in 1866. It is found on Java, Sumatra and Borneo and possibly also in the Philippines. The habitat consists of lowland forests. Adult males have an almost triangular white patch on the forewing costa postmedially with a straight exterior margin. Females have a basal black patch on the forewings with a central extension that almost reaches the marginal black area.