Data from: Multilocus phylogenetics of new world milkweed vines (Apocynaceae, Asclepiadoideae, Gonolobinae)

Subtribe Gonolobinae of the cosmopolitan family Apocynaceae is diverse and
represents the largest radiation of milkweeds in the New World (~500
species). The largest genus, Matelea, is an amalgam that was united
largely by a perceived lack of discrete morphological variation,
particularly in floral structures. Using plastid and nuclear DNA
sequences, we estimate a phylogeny of Gonolobinae using four chloroplast
loci and three cloned nuclear regions. We investigate monophyly of Matelea
and other established and provisional genera via a series of hypothesis
tests. We find variable support and considerable conflict among the gene
trees. Despite this, our data confirm the paraphyly of Matelea while
Gonolobus and other segregate genera receive some support as monophyletic
assemblages. We attribute conflicting signal in our data primarily to
incomplete lineage sorting, a likely result of rapid radiation. Ancestral
character reconstructions of growth form, fruit, and corolla morphology
reveal a woody twining growth form to be plesiomorphic with one to two
transitions to an herbaceous, non-twining growth form followed by one
putative reversal to the woody twining growth form in the subtribe.
Plesiomorphic states for fruit ornamentation and corolla shape are less
clear and these characters exhibit high levels of homoplasy. This study is
one of the most comprehensive phylogenies of gonoloboid milkweeds to date
and the first to sample multiple nuclear loci and include allelic data.