Data from: Phylogenomic loci define the generic boundaries of Gochnatieae and improve resolution at the species level in Moquiniastrum (Compositae)

Understanding the evolution of the tribe Gochnatieae (Compositae) has been
the subject of considerable effort in the past decade. This is due to the
key position of this tribe in the phylogeny of the sunflower family and
the corresponding implications for biogeographic and morphological
evolution of Compositae. Previous studies have confirmed the monophyly of
this tribe as well as most of the genera that belong to it. However,
phylogenetic resolution of Gochnatieae at both the genus- and
species-level has remained poor. A subset of new phylogenomic loci used in
this study has proven effective and has improved phylogenetic resolution
in this group. The results of this work demonstrate Gochnatieae is a
well-supported clade comprised of nine genera (Anastraphia, Cnicothamnus,
Cyclolepis, Gochnatia, Moquiniastrum, Nahuatlea,  Pentaphorus, Richterago,
Tehuasca). One recently described genus, Vickia, was not included in this
study; but its placement in Gochnatieae as a tenth genus in the tribe is
well-justified. The monospecific Cyclolepis, which had been circumscribed
within the tribe since its inception but was subsequently removed and
designated as incertae sedis since 2014, is also shown to belong to
Gochnatieae. We confirmed the monophyletic Moquiniastrum with two
well-supported subclades. Ancestral area reconstruction analyses show that
Gochnatieae originated in Eastern South America about 53 my. Apparently,
except for Cyclolepis and Richterago, the ancestors of the other genera of
Gochnatieae originated about 44 my from an area that now corresponds to
the central Andes. The presence of the genera in the Chaco phytogeographic
province, central Chile, and Mexico-United States-Caribbean is a result of
dispersal from the central Andes. The ancestral distribution of
Moquiniastrum corresponds to a large area comprising Eastern South America
and the current central Andes, about 32 my. Ancestral character state
reconstruction that included four characters indicates several states
associated with complex plant reproductive biology such as gynodioecy,
gynomonoecy, and polygamodioecy are derived in Gochnatieae as are
heterogamous capitula (in Moquiniastrum and Richterago), dimorphic and
subdimorphic corollas (in Cnicothamnus, Moquiniastrum, and Richterago),
and the presence of marginal female corollas (in Moquiniastrum and
Richterago). Within Moquiniastrum, two subclades (Densicephalum and
Polymorphum) exhibit divergent patterns of trait evolution associated with
these reproductive characters which suggests this genus can serve as a
model to understand the sexual system evolution in plants.