Research Paper

Taxonomic notes on Isodon (Nepetoideae, Lamiaceae) from Xizang, China: A new species and a new combination

Ya-Ping Chen, Chun-Lei Xiang

Published on: 31 March 2025

Page: 275 - 280

DOI: 10.6165/tai.2025.70.275

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    Abstract

    Isodon elegans, a new species from southeastern Xizang, China, is described and illustrated based on morphological evidence and geographic distribution, as well as our recent phylogenomic studies of the genus. It was previously misidentified as I. parvifolius, but the two species can be easily distinguished by lamina shape, calyx tooth shape, and corolla color and indumentum. Meanwhile, I. rungshiaensis, previously treated as a variety of I. irroratus, is elevated as an independent species within the genus. The two species are phylogenetically distantly related, and can be distinguished by the lamina shape and indumentum, petiole length, and corolla color.

    Keyword: Dry valley, Himalaya, Isodon elegans, Isodon rungshiaensis, Isodoninae, Ocimeae, Yarlung Zangbo River

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