Phylogenetics of the Antillean Goetzeoideae (Solanaceae) and their relationships within the Solanaceae based on chloroplast and ITS DNA sequence data

Coeloneurum, Espadaea, Henoonia, and Goetzea are shrubs and trees that are endemic to the islands of Cuba, Hispaniola, and Puerto Rico in the Greater Antilles. A phylogenetic analysis was conducted to elucidate the evolutionary relationships among them and with other major lineages of the Solanaceae. DNA sequences of the chloroplast genes ndhF rbcL, and trnL-trnF intron and intergenic spacer were obtained for twenty two taxa and sequences of the nuclear rDNA ITS region were obtained for eight taxa comprising a data set of over 5,000 bp. The inferred phylogeny groups the Antillean genera together with the South American Metternichia and Duckeodendron in a clade within the Solanaceae, pointing to a broader circumscription of the Goetzeoideae. Both chloroplast and nuclear datasets find the following relationships among the Antillean taxa: (Coeloneurum (Henoonia (Espadaea, Goetzea))). The South American genera Metternichia and Duckeodendron are the first and second sister groups, respectively, to the Antillean genera. The close relationship of Metternichia to the Antillean genera also is supported by pollen morphology. Phylogenetic inference suggests that the Antillean taxa first occuppied xeric environments and evolved into more mesic habitats Floral characteristics indicate evolution of pollination systems from nocturnal, insect-pollination in Duckeodendron and Metternichia to diurnal, bird-pollination in the Antillean genera. Duckeodendron and the Antillean genera produce drupes, but their contrasting morphology and anatomy suggest that these fruit types originated from separate evolutionary events.