Data from: Lithobieae and Eriocnemeae: two new neotropical tribes of Melastomataceae

Lithobium is a monotypic genus in the Melastomataceae restricted to
southeastern Brazil. Most previous students of the family have placed
these diminutive herbs into the Microlicieae, but some classifications
have assigned the genus to the Sonerileae or Bertolonieae. Eriocnema is
also a monotypic genus that has been included in the Bertolonieae,
Sonerileae, and also Microlicieae. Ochthephilus, yet another monotypic
genus, was assigned to the Merianieae, but lack of fruits and seeds, and a
paucity of collections, have made it difficult to correctly place in a
phylogenetic context. In this phylogenetic analysis, 91 species
representing 73 genera from across the Melastomataceae, including 24 of
the 27 genera putatively closely related to Lithobium, Eriocnema,
Ochthephilus, and Physeterostemon were sampled for seven molecular
markers, i.e., the nuclear ribosomal external transcribed spacer region
(ETS) and internal transcribed spacer region (ITS), the plastid accD–psaI
spacer region, ndhF, psbK–psbL, rbcL, and rpl16. Lithobium is on an
isolated branch and is not a member of any other clade, thus a new tribe,
Lithobieae, is proposed to accommodate it. In this analysis, Eriocnema and
Ochthephilus form a clade including Physeterostemon that is sister to the
Miconieae and separate from tribes that they have been associated with in
historical classifications, thus another new tribe, Eriocnemeae, is
proposed.