Buxaceae is a small family of basal eudicots comprising up to five genera (Buxus, Notobuxus, Pachysandra, Sarcococca, Styloceras) and about 120 species. The delimination of the family and the systematic relationships within the family have been problematic in the past. Our previous molecular study revealed two major clades: the clade of Buxus and Notobuxus, and the clade of Pachysandra, Styloceras, and Sarcococca.Pachysandra and Styloceras form a strongly supported sister group to Sarcococca. The African genus Notobuxus is embedded among African members of Buxus. The basic structure of inflorescences and flowers, in particular the development and trimery of the gynoecium, of Notobuxus is very similar to that of Buxus. The other major clade is also supported by identical basic floral structures as the dimery of the gynoecium or the very similar male flowers in Pachysandra and Sarcococca. Floral structure and development of representatives of all genera have been studied in detail and will be discussed in connection with the molecular results.

Key words: basal eudicots, Buxaceae, floral development, floral structure, molecular phylogeny