Elsholtzieae, the smallest tribe of the subfamily Nepetoideae (Lamiaceae), consists of approximately 70 species within eight genera. It is ecologically and economically significant, with members like the culinary and medicinal plant Perilla frutescens (shiso). However, the evolutionary relationships within the tribe have remained poorly understood due to limited data.
In a study published in Taxon, researchers from Xishuangbanna Tropical Botanical Garden (XTBG) and Kunming Institute of Botany (KIB) of the Chinese Academy of Sciences and their collaborators proposed merging two genera into an expanded Perilla and reinstating another to resolve long-standing classification issues.
The researchers leveraged an extensive analysis of five chloroplast DNA markers and two nuclear regions from a wide range of species. The results confirmed that several traditionally defined genera, including Keiskea, Elsholtzia, and possibly Perilla, were not natural groupings (non-monophyletic), meaning they contained species from different evolutionary lineages.
The researchers used the robust phylogenetic framework, combined with morphological and geographical evidence, to propose a revised classification.
They proposed a broader definition of the genus Perilla to include the genera Keiskea and Mosla. This merger resolves the non-monophyly of these groups and reflects their close evolutionary relationship. To maintain a natural classification, the genus Paulseniella has been reinstated to accommodate three species that were previously placed within the large genus Elsholtzia.The newly defined Elsholtzia in the strict sense was confirmed as a monophyletic group, containing five well-supported lineages.
"Previous studies hinted at problems with the generic boundaries in Elsholtzieae, but they were hampered by limited data," said LI Bo of XTBG. "Our research provides the missing pieces, offering a stable phylogenetic foundation that finally allows for a classification that truly reflects the evolutionary history of this tribe."
Contact
LI Bo Ph.D Principal Investigator
Xishuangbanna Tropical Botanical Garden, the Chinese Academy of Sciences
E-mail: hanbolijx@xtbg.ac.cn
First published: 30 October 2025
