Five new species of spiny solanums ( Solanum subgenus Leptostemonum Bitter; the Leptostemonum Clade) are described from the islands of the Pacific. Two of the new species are from Fiji ( S. pseudopedunculatum D.McClelland, sp. nov. and S. ratale D.McClelland, sp. nov.), two from New Caledonia ( S. memoayanum D.McClelland, sp. nov. and S. semisucculentum D.McClelland, sp. nov.), one from Papua New Guinea ( S. labyrinthinum D.McClelland, sp. nov.) and another from Vanuatu ( S. vanuatuense D.McClelland, sp. nov.). A new status and combination is provided for the rare Hawaiian endemic S. caumii (F.Br.) D.McClelland, comb. et stat. nov. and a new type designated for S. peekelii Bitter of Papua New Guinea, for which a description is also provided. All species are illustrated with digitized herbarium specimens, mapped and have been assigned a preliminary conservation status using current IUCN guidelines. Details of all specimens examined are provided in a Suppl. materials 1: file SM1.