Taxonomic and biogeographic implications of a phylogenetic analysis of the Campanulaceae based on three chloroplast genes

Campanulaceae are a large, nearly cosmopolitan angiosperm family that are well‐accepted as monophyletic but whose intrafamilial and intrageneric relationships are controversial. We used DNA sequences of the chloroplast genes atpB, matK, and rbcL to infer the phylogeny of 102 taxa in 41 genera plus four outgroup taxa. Our sampling represents a wide taxonomic and geographic diversity from within the family. Results from maximum parsimony and Bayesian analyses provide strong evidence for two major clades in the family, with the platycodonoids sister to the remaining members of the family, the wahlenbergioids and campanuloids. There are two clear divisions within the campanuloids that correspond well with the historical Campanula s.str. and Rapunculus groups of Boissier and Fedorov. The phylogenetic positions of the Northern European species Wahlenbergia hederacea and the genus Jasione remain unresolved. Our results also provide evidence that the large, inclusive genera Wahlenbergia and Campanula are polyphyletic, and the smaller, segregate genera Symphyandra, Prismatocarpus, and Legousia are not monophyletic. Insights are provided into the different biogeographic origins of several oceanic island endemics. Heterochaenia, Nesocodon, and Berenice occur in a single clade, which suggests a single colonization of the Indian Ocean Mascarene Islands. Conversely, Wahlenbergia linifolia and W. angustifolia of St. Helena Island in the mid‐Atlantic are not sister taxa. The Macaronesian taxa, Canarina canariensis, and Musschia aurea, which display convergent bird‐pollination adaptations and with Azorina vidalii of the Azores, woody growth form, fall into separate major lineages. The North American Campanulaceae also do not form a monophyletic group, providing evidence that these taxa are the descendents of multiple introductions onto the North American continent