A new species of Youngia (Asteraceae, tribe Cichorieae) from Yunnan, China

摘要

Youngia gongshanensis, a new species of Youngia sect. "Mesomeris" from Yunnan province of China is described and illustrated based on evidence from morphology and molecular phylogeny. The new species is superficially very similar to Y. atripappa having a solitary and erect stem and more or less lyrately pinnatisect leaves, but can be distinguished by capitula with 5-6 (vs. 12-15) florets, corolla tube glabrous (vs. sparsely pubescent with short white spreading hairs), pappus white (vs. grayish), bracts ovate to elliptic, distinct large (vs. very small, subulate). Parsimony analyses based on DNA sequence data of the nuclear ribosomal ITS shows that the new species is sister to Y. cineripappa with strong support, but the new species differs from the latter in having a glabrous corolla tube, smaller capitula with a lesser number of florets, and especially the white pappus.