The genus Voyria (Gentianaceae) consists of 19 tropical species of small, non-chlorophyllous and herbaceous mycotrophs. The genus shows extensive variation in pollen morphology, stem anatomy, and flower and seed morphology. Previous sequencing of the chloroplast derived trnL intron for over 100 gentians and Voyria failed to place the genus inside the family or even the order Gentianales due to extreme sequence divergence. Several new ribosomal 18S sequences show Voyria to be placed among the basal clades of the Gentianaceae. Nuclear ITS (internal transcribed spacer) sequences have also been produced and will be analyzed together with an earlier published morphological data set including all species in the genus. The ribosomal data does not appear particularly divergent relative to other gentians, whereas the ITS sequences differ markedly among presumably closely related taxa. Evolution of complete or partial mycotrophy has evolved at least three times independently in the Gentianaceae, and this will be discussed in a phylogenetic context.

Key words: Gentianaceae, molecular systematics, mycotrophy, phylogeny, Voyria