Monophyly and Major Clades of Meryta (Araliaceae)

Abstract Phylogenetic analyses of nuclear ribosomal ITS and ETS sequences yield considerable improvements in our knowledge of relationships, character evolution, and biogeography in Meryta (Araliaceae). This genus comprises ca. 30 species, all of which share simple leaves and a dioecious sexual system, a unique combination in Araliaceae. Meryta is distributed widely across the Pacific, but each of its species is endemic to only one or a few islands. Previous phylogenetic studies have included only a very limited number of exemplars from Meryta, but have suggested that the genus is related to the Southwest Pacific clade of Schefflera within the larger Polyscias-Pseudopanax group of Araliaceae. Our data confirm this previous placement and provide evidence for the monophyly of Meryta. There is no support for the recognition of three segregate genera, Botryomeryta, Schizomeryta, and Strobilopanax. Within Meryta, we have identified two major clades, one that unites the species from Fiji and New Zealand (both o...