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| Sinosenecio yangii D. G. Zhang & Q. Zhou, in Peng, Zhang, Deng, Huang, ... et Zhou, 2022. |
Abstract
A new species Sinosenecio yangii D.G. Zhang & Q. Zhou (Asteraceae, Senecioneae) from Guizhou Province, China, is described and illustrated based on its morphological characteristics and molecular evidence. It closely resembles S. confervifer and S. guangxiensis, the former in the scapigerous habit and smooth and glabrous achene surface, the latter in the calyculate involucre and purple abaxial leaf surface, and both in the shape and indumentum of leaf lamina, but differs markedly from the latter two in having fewer capitula and epappose achenes. Phylogenetic analysis based on nrITS and ndhC-trnV sequences shows that this new species belongs to the S. latouchei clade and is sister to S. guangxiensis with moderate support.
Keywords: molecular evidence, morphology, pappus
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| Sinosenecio yangii D. G. Zhang & Q. Zhou, A habitat B habit C–E leaves F capitulum G bottom and side of involucres (from left to right) H ray floret, disc floret and phyllary (from top to bottom). |
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| Sinosenecio yangii D. G. Zhang & Q. Zhou, A habit B capitulum C ray floret D disk floret E phyllary F stamens G style (drawing by Chu-miao Xie). |
Sinosenecio yangii D. G. Zhang & Q. Zhou, sp. nov.
Morphological observation (Fig. 1) showed that S. yangii, S. confervifer, and S. guangxiensis share obvious resemblance in the leaf blade shallowly undulate and suborbicular, adaxially densely to sparsely villous and abaxially sparsely pubescent or nearly glabrous (Table 2). In addition, S. yangii is similar to S. confervifer in the stem leafless or with 1–2 bract-like leaf and smooth achene surface, and to S. guangxiensis in the calyculate involucre. Nevertheless, S. yangii differs from both species in having fewer capitula (usually 1–3) and epappose achenes. The metaphase chromosomes of this species were counted to be 2n = 48 (Fig. 2A). The achene surface was glabrous and smooth (Fig. 2B) and the anther endothecial cell wall thickenings were polarized and radial (Fig. 2C).
Etymology: The species was named after Professor Qin-er Yang, an expert in the field of Asteraceae at the Chinese Academy of Sciences. The Chinese name is given as “亲二蒲儿根” (qīn èr pú ér gēn).
Distribution and habitat: Sinosenecio yangii is known from Lihua Town, Libo County, Guizhou Province, China (Fig. 6). It was collected from a rock cliff by the side of a rural road in this town, at an altitude of 347 m.
Jing-Yi Peng, Dai-Gui Zhang, Tao Deng, Xian-Han Huang, Jun-Tong Chen, Ying Meng, Yi Wang and Qiang Zhou. 2022. Sinosenecio yangii (Asteraceae), A New Species from Guizhou, China. PhytoKeys. 210: 1-13. DOI: 10.3897/phytokeys.5555.89480
