Phylogenetic relationships of the Lardizabalaceae and Sargentodoxaceae: Chloroplast and nuclear DNA sequence evidence

Abstract

A combined data set of three genes (atpB and rbcL from the chloroplast genome and 18S nuclear ribosomal DNA) was used to assess relationships among the genera of Lardizabalaceae and to explore the relationships of the family to Sargentodoxaceae and other families in the Ranunculidae (Fumariaceae, Eupteleaceae, Circaeasteraceae, Kingdoniaceae, Berberidaceae, and Menispermaceae). Lardizabalaceae and Sargentodoxaceae together comprise a monophyletic group. Sargentodoxa, Decaisnea, and Sinofranchetia, in that order, are basal within the Lardizabalaceae sensu lato. As in previous studies based on molecular and morphological data, the 'core' Lardizabalaceae (Boquila, Lardizabala, Akebia, Holboellia, and Stauntonia) characterized by laminar placentation, is well-supported as a monophyletic group. A subset of this clade consisting of three Asian genera (Akebia, Holboellia, and Stauntonia) is also a well-supported monophyletic group.