biostudies-literatureUnknown218Wang CKThe genus <i>Gelidocalamus</i> T. H. Wen, endemic to southern China, is a small but taxonomically problematic genus of Arundinarieae (Poaceae, Bambusoideae). During field work, a population of <i>Gelidocalamus</i> from Zixing, Hunan, was discovered, appearing to be distinct from our previously identified collection. Comparisons of the population of Zixing were performed by using scanning electron microscopy (SEM) and a plastid genome-based phylogeny. Morphologically, it was mostly similar to <i>G.multifolius</i>, but differed by culm leaf erect with densely white pubescence, apical branch sheath much longer than the internodes and foliage leaf larger. Phylogenetically, the new species was well-supported as a sister to the clade of <i>G.multifolius</i> + <i>G.tessellatus</i>, and the above three taxa were clustered in the <i>Shibataea</i> clade (IV) of Arundinarieae. Thus, the new species, formally named as <i>Gelidocalamuszixingensis</i> W.G.Zhang, G.Y.Yang & C.K.Wang, was described and illustrated herein.PhytoKeys29-45https://www.ebi.ac.uk/biostudies/studies/S-EPMC9846285biostudies-literature<i>Gelidocalamuszixingensis</i> (Poaceae, Bambusoideae, Arundinarieae), a new species from southern China revealed by morphological and molecular evidence.PMC9846285Zhang WGWang CKGuo CCGuo RYang GYfalse<i>Gelidocalamuszixingensis</i> (Poaceae, Bambusoideae, Arundinarieae), a new species from southern China revealed by morphological and molecular evidence.The genus <i>Gelidocalamus</i> T. H. Wen, endemic to southern China, is a small but taxonomically problematic genus of Arundinarieae (Poaceae, Bambusoideae). During field work, a population of <i>Gelidocalamus</i> from Zixing, Hunan, was discovered, appearing to be distinct from our previously identified collection. Comparisons of the population of Zixing were performed by using scanning electron microscopy (SEM) and a plastid genome-based phylogeny. Morphologically, it was mostly similar to <i>G.multifolius</i>, but differed by culm leaf erect with densely white pubescence, apical branch sheath much longer than the internodes and foliage leaf larger. Phylogenetically, the new species was well-supported as a sister to the clade of <i>G.multifolius</i> + <i>G.tessellatus</i>, and the above three taxa were clustered in the <i>Shibataea</i> clade (IV) of Arundinarieae. Thus, the new species, formally named as <i>Gelidocalamuszixingensis</i> W.G.Zhang, G.Y.Yang & C.K.Wang, was described and illustrated herein.2023-01-01T00:00:00Z20232026-04-08T11:09:40.269Z2025-04-05T19:41:29.11ZS-EPMC98462853676227110.3897/phytokeys.218.96849