PHYLOGENETIC-RELATIONSHIPS OF SAMBUCUS AND ADOXA (ADOXOIDEAE, ADOXACEAE) BASED ON NUCLEAR RIBOSOMAL ITS SEQUENCES AND PRELIMINARY MORPHOLOGICAL DATA

We inferred the phylogeny of Sambucus and Adoxa (Adoxoideae, Adoxaceae ) based on nucleotide sequences of the internal transcribed spacer (TT S) region of nuclear ribosomal DNA, preliminary morphology, and a comb ination of the two data sets. Our morphological analysis implies that Adoxa is nested within Sambucus, based primarily on herbaceous habit a nd aspects of flower morphology However, there is strong support for t he monophyly of Sambucus based on TTS sequences and in the combined an alysis, implying that morphological similarities shared by Adorn and t he two Australian species of Sambucus may have evolved independently T he relatively small variation in ITS sequences within Sambucus makes t he sequences easy to align, but results in some ambiguity due to a lim ited number of informative characters. Nevertheless, there are several well-supported clades within Sambucus. Species with paniculate inflor escences (sect. Botryosambucus) form a well-supported clade, within wh ich the red-fruited species are monophyletic. These results support th e view that paniculate inflorescences and red fruits evolved independe ntly in Sambucus and Viburnum. In all analyses S. ebulus and its relat ives (sections Ebulus and Scyphidanthe) form a clade supported by valv ate corolla lobes. Based on the combined analysis the first Adoxoideae may have been characterized by flowers with an equal number of carpel s and perianth parts, and more-or-less separated style branches/stigma lobes. If so, reduction in the number of carpels and fusion of styles occurred within Sambucus.