Description from Flora of China
Phaeanthus yunnanensis Hu, Bull. Fan Mem. Inst. Biol. 10: 125. 1940; Dasymaschalon yunnanense (Hu) Bân.
Climbers, to 6 m tall, woody. Branches densely hairy when young. Petiole 3-8 mm; leaf blade oblong to obovate-oblong, 10-16 × 3.5-6.8 cm, membranous to thinly papery, abaxially appressed hairy, secondary veins 10-14 on each side of midvein and adaxially elevated, base rounded, apex acuminate. Inflorescences axillary, 1-flowered. Pedicel to 2.5 cm. Sepals broadly ovate, ca. 1 mm. Outer petals ovate, ca. 3 mm; inner petals ovate to obovate, ca. 2.8 × 2 cm, outside densely puberulent, inside sparsely puberulent. Stamen oblong, ca. 2 mm; connectives apically truncate. Carpels ca. 13, oblong, ca. 2 mm, glabrous, very sparsely hairy, or pilose; ovules 2-5 per carpel; stigmas globose. Monocarp stipes ca. 1 cm; monocarps slightly moniliform, to 3.5 × 0.5 cm, with 2 or 3 joints; joints cylindric to ellipsoid, pilosulose. Fl. Oct, fr. Aug.
The taxonomic placement of this species within Desmos is questionable and requires further research.
● Mixed forests; 1000-1400 m. S Yunnan (Xishuangbanna).