Maximum likelihood (ML) phylogenetic tree bases on the 12 shared single copy genes. Numbers above nodes are bootstrap proportions from 1000 pseudoreplicates. O. lucimarinus, M. pusilla, V. carteri and P. patens were used as outgroups. The letters embedded below nodes: A = Grass; B = Eudicots; C = Asterids; D = Rosids; E = Malvidae; F = Fabidae; G = Brassicaceae. The double slashes indicate outgroups.