In the last 20 years, the relationships of the Begoniaceae have been redefined. Molecular phylogenies have shown that the family, along with its traditional allies Datiscaceae and Tetramelaceae, belongs to the Curcubitales, with the Cucurbitaceae, a relationships already foreseen, but also with Corynocarpaceae, Coriariaceae and Anisophylleaceae, relationships that had never been predicted on the basis of non-molecular data. To illustrate potential evolutionary trends in the order, significant morpho-anatomical characters are mapped onto the rbcL and 18S molecular trees. An independant phylogenetic analysis of morphological data is also presented, as well as a combined analysis of morphological and molecular data. Features of the order that attract attention include the plagiotropic architectural habit associated with spiro-distichous leaf disposition (to distichous-opposite), and the possibility that the primitive state for the ovary may have been inferior, evolving into superior ovaries in Coriariaceae-Corynocarpaceae. Gaps in our knowledge of the group, and the significance of this analysis in terms of Begoniaceae morphology are discussed. Biogeographic ramifications will also be considered.

Key words: Begoniaceae, biogeography, character evolution, Cucurbitales, morphological phylogeny