The phylogeny of Mallotus s.str. (Euphorbiaceae) inferred from DNA sequence and morphological data

Mallotus s.str. is a monophyletic, large, palaeotropical genus in the family Euphorbiaccae. We investigated the phylogeny of the genus in order to (1) determine the evolutionary relationships within the Mallotus s.str. clade: (2) assess whether the six sections as circumscribed in the traditional classification reflect clades and evaluate the characters used in the classification: and (3) determine what are additonal new clades and their supporting morphological characters. For this purpose we assembled different datasets: plastid (matK) and nuclear (gpd) DNA sequence, macromorphological features and leaf anatomical data. We found that Mallotus sect. Mallotus, sect. Polyadenii and sect. Stylanthus are monophyletic. M. sect. Axenfeldia and sect. Rottleropsis are plyphyletic, and M. sect. Philippinenses is paraphyletic. Six additional clades with morphological synapomophies were also identified. An analysis of quantiative morphological data, in combination with quanlitative morphological and molecular dartasets resulted in almost completely resolved phylogenies and increased support values. However, the higher-level relationships between the clades are not supported in out analyses and the position of many taxa is still ambiguous.