XVI International Botanical Congess

Six predominantly southern hemisphere tribes have long been considered related (Genisteae, Crotalarieae, Podalyrieae, Liparieae, Thermopsideae, Bossiaeeae, Mirbelieae and Brongniartieae). Phylogenetic analyses using morphology have raised problems, e.g. relationships of the last three (mainly Australian) tribes to each other and the other genistoid tribes, and the position of the anomalous African genus, Hypocalyptus. A phylogeny from the internal transcribed spacers of nuclear ribosomal DNA (ITS1 and ITS2) will be presented. Preliminary results support the monophyly of most tribes, and suggest that the Australian tribes are basal, whilst Hypocalyptus is more closely related to these than to the other African taxa. Biogeographic implications of this result will be considered.