Evidence from Antirrhinum majus indicates that transcription factors CYCLOIDEA (CYC), DIVARICATA (DIV), and RADIALIS (RAD) play a role in specifying floral symmetry. In bilaterally symmetrical flowers, CYC and RAD are implicated in dorsal identity, while DIV patterns ventral identity. In this study, we examined duplication events within the RAD-like gene family in Dipsacales and report the phylogenetic relationships of the RAD-like genes across Pentapetaleae. Like CYC-like and DIV-like genes, we found three Pentapetaleae clades of RAD-like genes: RAD1, RAD2, and RAD3, with AmRAD in the RAD2 clade. Unlike CYC-like and DIV-like gene families, only one of these duplications appears to have taken place around the diversification of the Pentapetaleae: RAD1 spans the monocots and eudicots, while RAD2 and RAD3 are Pentapetaleae specific. We found additional duplications within these gene clades in Dipsacales, especially within the Morinaceae, Dipsacaceae, and Valerianaceae, which also contain additional duplicat...