Glab. woody liane up to ± 10 m. tall. Lvs coriac., dark green above, paler below; imparipinnately 3-5-foliolate, on petioles up to ± 6 cm. × 4 mm., enlarged at base; scar oval to suborbicular; lateral lflts on petiolules ± 5 mm. long; lamina ± 5-9-(13) × 3-7-(8) cm., broad-elliptic to broad-obovate, entire, obliquely cuneately narrowed to base, apiculate to retuse; terminal lflt on petiolule to 2 cm. long; lamina 8-12-(15) × 5-9 cm., broad-elliptic to broad-obovate, cuneately narrowed to base, retuse to apiculate. Infl. with up to 30 fls in corymbose compound cyme on stout peduncle ± 2-3 cm. long; pedicels stout, c. 1 cm. long, opp., us. trichotomously branched. Calyx green, velvety without, to c. 2.5 × 1 cm., tubular, (3)-4-(5)-lobed, splitting to base as fl. matures. Corolla delicately creamy white, with very pale green flush, tomentose without; tube cylindric, ± 3 × 1·5 cm., limb 2-lipped; lower lip entire, 2 × 1 cm., upper lip 4-lobed, ± 4 × 5 cm., each lobe tapering to subacute recurved apex. Stamens us. 4, to c. 5-6 cm. long, 2 outer > 2 inner; filaments adnate to tube for c. 1 cm., at point of separation invested by slender hairs. Anthers orange, c. 1 cm. long, cells diverging; staminode filiform, ± hairy, us. short, occ. long, sts represented by fully developed stamen. Style slender, extending to mid-anther position with a sharp double flexure in its upper third; stigma truncately 2-lobed. Ovary bilocular, the 2 placentae in each loculus occupying the thickened outer parts of the septum. Fr. a woody subcylindric capsule to 19 × 3·5 cm., splitting loculicidally from the base into two boat-shaped valves which separate from the septum. Seeds very many, densely packed, flattened, c. 1 × 2.5 cm. including broad membr. wing.