PHYLOGENETIC-RELATIONSHIPS IN THE CAMPANULALES BASED ON RBCL SEQUENCES

Phylogenetic relationships within the angiosperm order Campanulales were investigated by comparative sequencing of the chloroplast gene rbcL. Complete rbcL sequences were obtained for ten species in six families within the order. These data were analyzed along with previously published rbcL sequences from other taxa (for a total of 117 species) within the subclass Asteridae and outgroups, producing 32 equally parsimonious trees. A subset consisting of 44 of these taxa was then chosen and more rigorous analyses performed, resulting in four equally parsimonious trees. Results indicate that two major clades roughly corresponding to traditionally circumscribed Asterales and Campanulales exist as sister taxa. In particular, the rbcL trees indicate that Sphenoclea is not a member of Campanulales or Asterales, that Pentaphragma is more closely allied to Asterales than Campanulales, that the Cyphiaceae are not monophyletic, that Campanulaceae and Lobeliaceae are not sister taxa, and that Stylidiaceae are correctly placed within Campanulales.