Petrocodon asterocalyx F.Wen, Y.G.Wei & R.L.Zhang, a new species from the Danxia landform area in Guangxi, South China, is described and illustrated based on molecular and morphological data. The molecular evidence shows that the new species is recovered in a weakly supported clade. Within this clade, the new one is morphologically similar to P. hancei (Hemsl.) A.Weber & Mich.Möller and P. coriaceifolius (Y.G.Wei) Y.G.Wei & Mich.Möller, and it can be distinguished from the former by calyx lobes 20–40 × 2–3 mm, corolla 2.5–3.0 cm long, filaments sparsely erectly pubescent, anthers sparsely pubescent, staminodes 3, and stigmas 2; from latter by leaf blades rhombic-oblong or rhombic, base shallowly cuneate, margin crenulate to serrate, calyx lobes linear, 20–40 × 2–3 cm, and anthers 3.5–3.8 mm long, sparsely pubescent and elliptical.
Petrocodon asterocalyx, a new species of Gesneriaceae from Guangxi, China