The neotropical genus Camptosema in its southern distribution is represented by the following four species: Ca. paraguariense, Ca. praeandinum, Ca. rubicundum and Ca. scarlatinum. Ca. rubicundum is the only species with all the diagnostic characters of the genus, i.e. tubular calyx. The other three taxa are related morphologically and cytologically to Galactia and Collaea, two closely allied genera in the subtribe Diocleinae. Individual and combined phylogenetic analyses of morphology, ITS and trnL-F were conducted to examine the position of these species as well as to explore their relationship with Galactia and Collaea species in southern South America. In none of the analyses does Camptosema species form a monophyletic group. Instead, they are scattered in different groups. These results together with cytological, morphological and AFLP data provide good support for re-evaluating the taxonomic position of these species within Camptosema.