Oxylobus (Asteraceae) analysis DNA sequence data

A molecular phylogenetic investigation was carried out to clarify aspects
of the systematics of Oxylobus, a primarily Mexican alpine genus of
Eupatorieae.  Analysis of sequence data from two nuclear (nrDNA
ITS, ETS) and three plastid markers (rbcL, ndhF, matK) confirmed the
monophyly of Oxylobus and placed species of Ageratina as its sister
group.  A survey of 56 samples of Oxylobus using nrDNA ITS and
ETS provided support for the currently accepted species, and showed the
recently described O. coyulensis to be distinct and the sister group to
the rest of the genus.  The results also confirmed the placement
of O. juarezensis in synonymy with O. subglabrus.  The results of
a broad survey of Ageratina for ITS data showed that it is likely not
monophyletic as currently circumscribed.  The phylogenetic
results also highlighted the distinctiveness of Piqueria and Piqueriopsis
as a distinct clade at the base of Eupatorieae.