Seringia J.Gay and Keraudrenia J.Gay are widely spread in Australia, and one species occurs in Madagascar. Revision of these closely related genera suggested that neither genus is monophyletic on the basis of morphological or preliminary molecular data. As a result, Keraudrenia is subsumed into Seringia. There are now 20 species of Seringia, including the currently accepted type species Seringia platyphylla J.Gay (=Seringia arborescens (W.T.Aiton) Druce). Five new species S. adenogyna C.F.Wilkins, S. cacaobrunnea C.F.Wilkins, S. elliptica C.F.Wilkins, S. undulata C.F.Wilkins and S. saxatilis C.F.Wilkins are described. Four species of Keraudrenia initially described as Seringia and recognised as the latter by F. J. H. von Mueller are reinstated (S. adenolasia F.Muell., S. corollata Steetz, S. lanceolata Steetz, S. nephrosperma F.Muell.). Five previous combinations of Keraudrenia and Seringia as Seringia are recognised (S. hermanniifolia (J.Gay) F.Muell., S. hillii (Benth.) F.Muell., S. hookeriana (Walp.) F.Muell., S. integrifolia (Steud.) F.Muell., S. velutina (Steetz) F.Muell.) and five new combinations are made (S. collina (Domin) C.F.Wilkins & Whitlock, S. denticulata (C.T.White) C.F.Wilkins & Whitlock, S. exastia (C.F.Wilkins) C.F.Wilkins & Whitlock, S. katatona (C.F.Wilkins) C.F.Wilkins & Whitlock, S. macrantha (Baill.) C.F.Wilkins & Whitlock. Keraudrenia collina var. multiflora Domin is placed in synonymy under S. nephrosperma F.Muell. Keraudrenia corollata var. denticulata C.T.White is recognised as a distinct species, S. denticulata (C.T.White) C.F.Wilkins & Whitlock. Anatomical studies, taxonomic descriptions, distribution maps, illustrations and identification keys are presented for Seringia, and an identification key to genera of the tribe Lasiopetaleae is provided.