Data from: Plastid phylogenomic analysis of Podostemaceae with an emphasis on Neotropical podostemoideae

Podostemaceae are a clade of aquatic flowering plants that form important
components of tropical river ecosystems. Species in the family exhibit
highly derived growth forms and high vegetative phenotypic plasticity,
both of which contribute to taxonomic confusion. The backbone phylogeny of
the family remains poorly resolved, many species remain to be included in
a molecular phylogenetic analysis, and the monophyly of many taxa remains
to be tested. To address these issues, we assembled sequence data for 73
protein-coding plastid genes from 132 samples representing 68 species
(~23% of described species) that span the breadth of most major taxonomic,
morphological, and biogeographic groups of Podostemaceae. With these data,
we conducted the first plastid phylogenomic analysis of the family with
broad taxon sampling. These analyses resolved most nodes with high
support, including relationships not recovered in previous analyses. No
evidence of widespread, well-supported conflict among individual plastid
genes and the concatenated phylogeny was observed. We present new evidence
that four genera (Apinagia, Marathrum, Oserya, and Podostemum), as well as
four species, are not monophyletic. In particular, we show that Podostemum
flagelliforme should not be included in Podostemum and is better
recognized as Devillea flagelliformis, and that Marathrum capillaceum is
embedded within Lophogyne s.l. and should be recognized as Lophogyne
capillacea. We also place a previously unsampled and undescribed species
that likely represents a new genus. In contrast to previous studies, the
neotropical genera Diamantina, Ceratolacis, Cipoia, and Podostemum are
resolved as successive sister groups to a clade of all paleotropical
Podostemoideae taxa sampled, suggesting a single dispersal event from the
neotropics to the paleotropics in the history of the subfamily. These
results provide a strong basis for improving the classification of
Podostemaceae and a framework for future phylogenomic studies of the clade
employing data from the nuclear genome.