Extensive nearly glabrous slender tuberous twiner with mostly glabrous stems. Leaves hairy above or glabrous to 120mm x 50mm. Few to many-flowered axillary umbellate cymes of 3-12 flowers with bracts to 10mm long, glabrous calyx to 8mm long, sweet-scented bright yellow glabrous corolla to 80mm long with 5 lobes sometimes with purplish tinge, tube 40mm long, lobes 30mm long.