Large, woody climber; branches slender, terete, twining; leaves opposite, coriaceous, broadly elliptic, oblong, shortly acuminate at apex, rounded or cordate at base, rarely pubescent, often glabrous above; flowers small, crowded in umbelliform cymes; peduncles densely tomentose; pedicels slender; calyx pubescent, deeply 5-lobed; lobes oblong, obtuse; corolla pale yellow, campanulate or urceolate, lobes-5, short, glabrous, thick, triangular, obtuse, recurved, as long as the tube, overlapping to right; corona-lobes fleshy, adnate to corolla throat, column short; filaments connate; anther tips small, membranous, pollen-masses solitary in each anther cell, ovoid-oblong, waxy, pedicelled, erect; stigma large, conical, clavate or capitate, often exserted; follicles slender or turgid, terete, smooth, lanceolate, 5-7.5 cm long, glabrous, acuminate at the distal end; seeds ovoid or oblong, flat 1.2 cm long, pale brown, broadly margined.