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| Koenigia bingchachaensis Bo Xu & H. Sun, in Xu, Sun et Luo. 2026. |
ABSTRACT
A new species, Koenigia bingchachaensis Bo Xu & H. Sun (Polygonaceae), is described and illustrated based on material from the alpine subnival of Zayü County, Xizang, China. The species is characterized by a perennial tufted habit, extensively developed braided-fissured rhizomes, numerous simple spreading stems, prominently petiolate (1.5–4.0 cm) and arched leaves, and paniculate inflorescences borne both terminal and axillary with a short, twisted rachis. Morphologically, it is closely allied to K. tortuosa and K. hookeri, but can be readily distinguished from both by a stable combination of vegetative and reproductive characters. Molecular phylogenetic analyses based on complete plastome and nuclear ribosomal ITS sequences strongly support K. bingchachaensis as a distinct species, resolving it as a well-supported sister lineage to the clade comprising K. hookeri and K. tortuosa. The integrative taxonomic approach, combining detailed morphology with molecular data, unequivocally confirms the specific status of K. bingchachaensis. The discovery expands the known diversity of Koenigia and highlights the potential for uncovering unique plant lineages in the extreme alpine environments of the Qinghai–Tibet Plateau.
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| Koenigia bingchachaensis: (A) sampling location; (B) plant habit; (C) type specimen; (D) plant showing underground roots; (E) the scanning electron micrographs of pollen grains and achenes; and (F) dissected structures of roots, inflorescence, perianth, ovary, and seeds. |
Koenigia bingchachaensis Bo Xu & H. Sun sp. nov.
Diagnosis: Within the genus Koenigia, K. bingchachaensis is morphologically distinctive and highly diagnostic. Although it shares the characteristic of terminal paniculate with K. tortuosa and K. hookeri, the new species can be clearly differentiated by the following combination of features: its unique tufted growth habit; elongated and braided-fissured rhizomes that may fragment; simple and spreading stems; and leaves with prominent petioles (1.5–4.0 cm long) that are arched and enclose the plant. Addtionally, its paniculate inflorescences occur both terminal and axillary, with a short, twisted rachis often concealed within the leaf cluster. Taken together, these morphological characteristics support its distinction from all other known species in the genus Koenigia.
Etymology: The specific epithet “bingchachaensis” refers to the renowned Bingchacha Highway (part of National Highway G219), also known as the new Yunnan-Xizang corridor, which traverses a remote and rugged region of the Himalayas. The type specimen was collected along this very road. The construction of this highway has been pivotal in providing access to this previously inaccessible and botanically underexplored area, leading directly to the discovery of this new species. The name thus commemorates the highway's role as a unique link between human engineering and scientific discovery, a conduit that unveiled a hidden natural treasure.
Bo Xu, Hang Sun, Dong Luo. 2026. Koenigia bingchachaensis (Polygonaceae), a remarkable New Species from the Alpine Subnival of Bingchacha, Zayü, Xizang, China. Ecology and Evolution. DOI: doi.org/10.1002/ece3.73290 [28 March 2026]
Koenigia bingchachaensis Bo Xu & H. Sun (Polygonaceae), a remarkable new species from the alpine subnival of Zayü County, Xizang, China, is described and illustrated. The integrative evidence from morphology and phylogenetics confirms the status of K. bingchachaensis as a new species, which also highlights the ongoing discovery of unique biodiversity in poorly explored alpine regions of the Qinghai–Tibet Plateau.
