The Microlicieae (11 genera, c. 240 species) are one of eight major clades identified by morphological and molecular data in the predominantly tropical family Melastomataceae. Microlicieae are neotropical and most species-rich in Brazil. They have traditionally been defined by reniform, oblong seeds with a foveolate testa, in combination with capsular fruits, basally prolonged anther connectives, rostrate anther thecae, and glabrous ovaries. The interpretation of seed morphology, however, is not always straightforward and the placement of several genera therefore dubious. We used DNA sequences from the nuclear ribosomal internal transcribed spacer (ITS) region and the chloroplast rpl16 intron to test the monophyly of the tribe and infer generic relationships. Maximum likelihood analysis of an rpl16 data set that included ten of the tribe’s 11 genera plus a broad sample of genera from a published analysis of the family placed Chaetostoma, Lavoisiera, Microlicia, Rhynchanthera, Stenodon, and Trembleya together. Of the remaining four genera, Eriocnema was placed within Miconieae, Siphanthera as sister to Aciotis of Melastomeae, Castratella as sister to Monochaetum of Melastomeae, and Cambessedesia in a polytomy near the base of higher Melastomataceae. Within core Microlicieae, a combined ITS + rpl16 maximum likelihood analysis rooted with Rhynchanthera yielded the topology (Trembleya (Chaetostoma (Stenodon (Microlicia, Lavoisiera)))). This analysis placed the nine species of Microlicia sampled together, whereas Trembleya was paraphyletic with respect to the remaining core Microlicieae. Lavoisiera (seven species sampled), recently redefined to include species with a partially inferior ovary, laterally flattened placental intrusions, and capsular fruits that dehisce from the base to the apex, was supported as monophyletic. In agreement with a recent study, core Microlicieae have reniform or oblong foveolate seeds, whereas seed morphology in the four genera requiring tribal reassignment can be accommodated in other tribes.

Key words: ITS, Melastomataceae, Microlicieae, phylogenetics, rpl16