PHYLOGENETIC-RELATIONSHIPS IN SARRACENIACEAE BASED ON RBCL AND ITS SEQUENCES

Sarraceniaceae, a New World family of carnivorous plants, consist of S arracenia, Heliamphora, and the monotypic Darlingtonia. Despite extens ive interest in these plants, few explicit phylogenetic hypotheses are available for the family. We investigate phylogenetic relationships i n the family using sequences of the internal transcribed spacer region s of nuclear ribosomal DNA (ITS) and of the chloroplast gene rbcL. One representative of each genus was sequenced for rbcL, whereas represen tatives of all species in the family, except for H. heterodoxa and H. ionasii, were sequenced for ITS. Both the ITS- and rbcl-based phylogen ies demonstrate that Sarracenia and Heliamphora form a monophyletic gr oup that is the sister group of Darlingtonia. Sarracenia and Heliampho ra are each well supported monophyletic genera. In our restricted samp ling of Heliamphora, H. nutans is the sister of H. minor and H. tatei. Our results provide little resolution of relationships among species of Sarracenia, but identify one dade that consists of all species exce pt S. alata. Within this clade are two smaller clades comprising:-1) S . purpurea and S. leucophylla,-and-2) S. flava, S. minor, and S. psitt acina.