Description from Flora of China
Stemodia grandiflora Buchanan-Hamilton ex D. Don, Prodr. Fl. Nepal. 89. 1825.
Annuals, scandent, much branched, densely pilose. Branches slender, flexuous, 15-80 cm. Leaves opposite; petiole to 7 cm; leaf blade ovate, to 20 cm below, noticeably decreasing in size upward, margin undulate and serrate; lateral veins 6-10 on each side of midrib. Inflorescences spicate, lax, to 25 cm. Flowers subsessile, solitary from bract axils. Calyx 7-8 mm, glandular hairy; lobes equal, spreading flat, orbicular, apex obtuse. Corolla golden yellow, to 3 cm; tube 2-3 X as long as calyx, sparsely hairy; throat with 2 oblong red-punctate plaits; lower lip broader than wide, to 2.5 cm, lateral lobes oblong, middle lobe smaller than other lobes, orbicular, and emarginate; upper lip short and orbicular, emarginate. Filaments hairy below middle. Ovary sericeous. Capsule ovoid, apex exserted from persistent calyx. Seeds ca. 0.5 mm.
S Xizang [Bhutan, India (Darjeeling), Nepal, Sikkim].