Neillia daloushanensis, a new species of Neillia (Rosaceae) from southwest China

Through detailed morphological comparison and robust molecular evidence, we confirm <i>Neilliadaloushanensis</i> M.T.An & Xu Wu as a new species of Rosaceae from Guizhou province, southwest China. Morphologically, <i>N.daloushanensis</i> closely resembles <i>N.gracilis</i> but differs in several key traits: it is a creeping liana rather than a low subshrub; its stems are 0.6-1.5 cm long compared to the slender stems less than 0.5 cm tall in <i>N.gracilis</i>; its leaves are larger, measuring 5-9 × 3-6 cm vs. 2.5-3.5 × 2-3 cm; stipules are sessile, clasping, and larger (0.8-1.3 × 0.6-1.1 cm) rather than peitiolate and smaller (0.4-0.6 × 0.3-0.5 cm) without clasping; calyx tubes are densely pilose on both surfaces and bear stipitate glands abaxially, in contrast to the slightly pubescent, glandless calyx tubes of <i>N.gracilis</i>; and the seed number ranges from 2 to 4 instead of consistently 2. These morphological distinctions are further corroborated by molecular phylogenetic analysis based on 703 single-copy nuclear genes, supporting the recognition of <i>N.daloushanensis</i> as a distinct species within the genus.