<i>Aster tongrenensis</i> (Asteraceae), a remarkable new species from Guizhou, China

Aster tongrenensis (Asteraceae), a remarkable new species from Guizhou, China, is here described, illustrated and compared with related taxa based on integrated evidence from morphology, micromorphology and molecular phylogeny. Morphological and micromorphological observations indicate that A . tongrenensis is most similar to A . saxicola , but can be distinguished from the latter by its glabrous (versus puberulent) stem, green (versus purplish‐red) phyllary apices, capitula 1.3–1.8 cm in diameter (versus 2.4–3.3 cm in diameter), disc florets number (8–10 versus 10–18), and sparsely strigose and minutely stipitate glandular achenes (versus puberulent and densely strigose). Phylogenetic analyses of combined ITS and ETS sequence data support the close relationship between A . tongrenensis and A . saxicola . The new species is a fertile diploid plant and its karyotype is 2n = 18. Preliminary data on its ecology, distribution, and conservation status (assessed as ‘Data Deficient', DD) are provided.