Genomic data provide a robust phylogeny backbone for Rhodiola L. (Crassulaceae) and reveal extensive reticulate evolution during its rapid radiation

•A well-supported backbone phylogeny for Rhodiola was reconstructed using the GBS data.•Extensive gene flow and introgression events were detected, both between non-sister and sister species.•Rhodiola may have undergone adaptive radiation, and climate cooling in the Miocene played an important role in triggering the radiation.