ABSTRACT The origin and radiation of plant lineages is one of the central topics in evolutionary biology, and the diversification of Orchidaceae is of more concern and still perplexing. In this study, we selected to resolve the origin and radiation of Orchidaceae by focusing on the Calanthe alliance. Using nrITS, plastome sequences, and single‐copy SNP data, we systematically reconstructed its phylogeny and spatiotemporal evolution. The monophyly of the six genera was confirmed; however, conflicts between the plastome and single‐copy SNPs were observed at both the species and generic levels. In addition, the Calanthe alliance originated in the late Oligocene, during a period of sharp climate cooling, while its three major clades were established in the warmest phase of the Cenozoic. The ancestral area of Calanthe was located in Southeast Asia, and the uplift of the Himalayas and the Tibetan Plateau in the Late Miocene drove the dispersal of Calanthe from tropics to subtropical and temperate areas. The diversification of the Calanthe alliance followed a two‐step pattern: an initial steady increase in lineages with adaptation to broader elevational ranges, and a second phase of relative stasis followed by recent speciation. Thus, we deemed that the montane area, as an essential distribution area of Calanthe , functioned as both “museum” and “cradle” in the diversification history of this genus. This work provides new insight into the classification and historical dynamics of complicated taxa in Orchidaceae.
Zhai et al. (Sun,) studied this question.