A phylogenetic parsimony analysis based on 76 morphological characters of 43 Mallotus, 3 Macaranga, 1 Claoxylon, 1 Cleidion, 1 Sampantaea, and 1 Wetria species, resulted in 314 trees of length 602 (CI = 0.600, RI = 0.685), which could be summarized in a well resolved consensus cladogram. This consensus cladogram indicates that the genus Mallotus is possibly polyphyletic and that sections Hancea and Oliganthae should probably be excluded from Mallotus. It is proposed to refer to Mallotus as either Mallotus sensu lato (with the sections Hancea and Oliganthae) or Mallotus sensu stricto (excluding the sections Hancea and Oligantae). The genus Macaranga forms a monophyletic group within Mallotus s.s. The traditional section delimitations within Mallotus s.s. do not circumscribe monophyletic clades of species with the exception of section Polyadenii. It is suggested that sections Stylanthus, Rottlera, Mallotus, and the genus Macaranga should form one monophyletic clade. Sections Axenfeldia and Rottleropsis remain unresolved, but are probably closely related. The position of Macaranga within Mallotus suggests that Macaranga evolved from pioneer ancestors that lived in open, scrub-like vegetation. It is hypothesised that Macaranga originated relatively recently in South East Asia during the Oligocene or early Miocene (between 38 and 15 million years ago).

Communicating Editor: Paul Wilson