Woody vine; stem 0.5-0.7 cm diam., with a relatively thin bark; branchlets glabrous; pseudostipules lacking. Leaves: petiole thin, 3-5 cm long; blade triangular, 11-17 x 9-12 cm, glabrous, shining above, greyish, pubescent beneath, apex long acuminate, acumen 2-2.5 cm long, base straight to slightly cordate; lateral veins submarginal at base. Inflorescence axillary to cauline, racemes thin, long (up to 25 cm), with a long peduncle, bearing 15-20 flowers with minute (< 1 mm long) petiolate bracts; pedicels very thin, 3 cm long. Flowers: ovary 1 cm long; perianth entirely yellow, glabrous; utricle globose, about 0.5 cm in diam.; tube slightly funnel-shaped, 1.5 cm long; limb funnel-shaped, inferior lobe widely elliptic, 2 x 3-3.5 cm, superior lobe linear, twisted, about 4 cm long, shortly papillose inside. Fruit unknown.