Within the family Rubiaceae, the Spermacoceae sensu lato were
postulated on basis of the molecular evidence from the rbcL gene.
This broadened tribe includes the former tribes Hedyotideae,
Knoxieae and Spermacoceae sensu stricto. Two clades were recogni-
sed within this morphological very diverse concept. The first aim
of our study is to document these two groups morphologically and
anatomically; special attention will be paid on pollen and seed
morphology. These results will then be used to select taxa for a
molecular study of the group. The molecular study is carried out
in order to refine the relationships within the study group and
to provide an evolutionary framework to discuss the morphological
variation.