Orobanchaceae, as recently redefined, has 88 genera and ca. 1530 species. Most taxa are distributed in temperate regions of the world with the highest density of genera and species in the northern hemisphere and in Old World floristic regions. We sequenced the nuclear rDNA 5.8s and ITS regions from 29 parasitic and six nonparasitic genera from Lamiales to reconstruct the phylogeny of Orobanchaceae. Our sampling included all of the major parasitic genera and several of the smaller genera from throughout the range of distribution. The ITS phylogeny supports the monophyly of Orobanchaceae with Lindenbergia as the basal lineage. Genera with distributions in southern and eastern Africa are located in the most derived position of the tree. The topology of the ITS tree suggests an origin of Orobanchaceae in Asia with subsequent migration of elements to North America and the Mediterranean region via the Tethyan seaway, followed by dispersal to northeastern Africa and a secondary diversification of genera throughout the southern hemisphere.

Key words: biogeography, Orobanchaceae, parasitic plants, phylogeny, Scrophulariaceae