Phylogenetic relationships in the Gesnerioideae (Gesneriaceae) based on nrDNA ITS and cpDNA trnL-F and trnE-T spacer region sequences

The Gesnerioideae includes most of the New World members of the Gesneriaceae family and is currently considered to include five tribes Beslerieae, Episcieae, Gesnerieae, Gloximeae, and Napeantheae This study presents maximum parsimony and maximum likelihood phylogenetic analyses of nuclear ribosomal DNA internal transcribed spacer regions (ITS), and the chloroplast DNA trnL intron, trnL-trnF intergenic spacer region, and trnE-trnT intergenic spacer region sequences The ITS and cpDNA data sets strongly support the monophyly of a Beslerieae/Napeantheae clade. an Episcieae clade, a Gesnerieae clade: a Gloximeae clade minus Sinningia, Sinningia relatives, and Gloxinia sarmentiana, and a Sinningia/Pahavana/Vanhouttea clade. This is the first study to provide strong statistical support for these tribes/clades These analyses suggest that Sinningia and relatives should be considered as a separate tribe Additionally, generic relationships are explored, including the apparent polyphyly of Gloxama Chromosome number changes are minimized on the proposed phylogeny, with the exception of the n = 11 taxa of the Gloximeae. Scaly rhizomes appear to have been derived once in the Gloximeae sensu stricto The number of derivations of the inferior ovary is unclear either there was one derivation with a reversal to a superior ovary in the Episcieae. or there were multiple independent derivations of the inferior ovary.