The Australasian genus Scotocyma Turner is revised, containing the species S. albinotata (Walker), S. legalis (Warren), S. asiatica Holloway, S. scotopepla Prout, stat. n., S. manusensis Prout, stat. n., S. mimula (Warren), stat. n. and S. miscix Prout. Scotocyma euryochra Turner, syn. n., S. idioschema Turner, syn. n., S. ischnophrica Turner, syn. n. and S. transfixa Turner, syn. n. are regarded as synonyms of S. albinotata. Four species are described as new: S. samoensis, sp. n., S. sumatrensis, sp. n., S. rutilimixta, sp. n. and S. longiuncus, sp. n. Lectotypes are designated for S. scotopepla, S. manusensis and S. miscix. All species are illustrated, and keys to species and distribution maps are provided. A phylogenetic analysis was performed to test the monophyly of the genus and to examine distribution patterns of the species. A biogeographical discussion is included. The tribal position of the genus is clarified and relationships to closely related genera are discussed.