Polygonatum caulialatum, a new species of medicinal plant of Polygonatum (Asparagaceae) from Sichuan, China

A new species of Polygonatum (Asparagaceae), Polygonatum caulialatum S. R. Yi from Bashan canyon of Xuanhan, Dazhou, Sichuan, China, is described in this paper, it is similar to P. cyrtonema Hua and P. odoratum (Miller) Druce in appearance for stem glabrous, leaves alternate, corolla campanulate, stamens not exposed, ovary glabrous and berries black, but differs from the former in middle and upper stem slightly flat with two distinct narrow wings, inflorescences 1–2(–3)-flowered, longer perianth lobes, filaments cylindrical and apically not inflated, longer styles and more seeds per berry; and differs from the latter in thicker moniliform rhizome, middle and upper stem slightly flat with two distinct narrow wings, longer perianth lobes, filaments cylindrical, longer anthers and styles, more seeds per berry.