Tree to 35-40 m; d.b.h. to 40(-100) cm; crown drooping, bole cylindrical, fissured with some flutes present; bark pale grey; young branches drying black sometimes sparsely spotted with white lenticels, with blue-greyish wax layer; old branches ash-grey to brown. Petioles 8-14 mm long, 1-2 mm in diameter, leaf lamina inserted side, broadly grooved adaxially, sometimes with blue-greyish wax layer. Leaf lamina 11-50 cm long, 4-14 cm wide, length:width ratio 2-3.5, narrowly obovate to obovate or narrowly elliptic to elliptic, base cordate to rounded or rarely cuneate, apex acuminate, acumen 10-15 mm long, membranous to coriaceous, glabrous, green above, pale green below; midrib raised and glabrous adaxially, prominent and glabrous abaxially; secondary veins 13-23 pairs, uniformally curving upwards, glabrous. Flowers single, leaf opposed, pendulous. Flowering pedicels 7-27 cm long, ca. 2 mm in diameter, glabrous, light green stained with dark purple patched, with blue-greyish wax layer. Upper bract inserted central to subapically on the pedicel, 1.5-4 cm long, 0.8-3 cm wide, length:width ratio 2-2.5, elliptic to obovate, base decurrent, apex acute to attenuate, glabrous, green with dark purple streaks; margins undulate, glabrous. Sepals 2-4 cm long, 0.7-1.7 cm wide, length:width 2-2.5, elliptic to ovate, base truncate, apex attenuate, glabrous, pale yellow densely streaked with purple to completely dark red; reflexed upwards, falling when in fruit, margins strongly undulate, glabrous. Inner and outer petals basally fused running down the pedicel for 6-8 mm before reflexing upwards. Outer petals 4-10.5 cm long, 2-4 cm wide, length:width ratio 1.8-3, narrowly ovate to ovate, base truncate, apex acute, glabrous, deep yellow at base streaked with dark red, pale yellow spotted dark purple when younger; arc shaped and dropping, margins strongly undulate, glabrous. Inner petals 25-35 mm long, 25-30 mm wide, length:width ratio 1-1.5, clawed cordate, base cordate, apex acute to obtuse, glabrous, basal lobes of lamina covered with short erect hairs, white with red central vein on the outside, white and specked with red-yellow on the inside; margins straight, covered with short curly hairs, connivent over receptacle; claw 2-5 mm long, 6-8 mm wide, claw:inner petal ratio 0.08-0.15, glabrous, yellow turning dark red. Receptacle 6-9 mm in diameter, strongly convex. Stamens in 16-20 rows, 1.8-2 mm long, connective shield ca. 0.2 mm long, elongated, covered with short erect hairs, those of inner whorl not elongated over ovary wall, white. Ovary partially overtopping stamens, 4-5 mm long, 4-5 mm in diameter, light green at anthesis; stigma ca. 3 mm in diameter, sparsely covered with short erect hairs, yellow-green. Fruiting pedicels to 30-35 cm long, 10-15 mm thick, woody, dark brown, with a clear scar of the bracteole, glabrous. Fruits 9-15 cm long, 8-15 cm in diameter, globose, 2-3 mm in diameter, smooth, finely longitudinally ribbed, lenticellate, green with white dots turning pale yellow when mature; pericarp 1-1.5 cm thick. Seeds 15-22 mm long, 10-13 mm wide, transversely ellipsoid, packed in white pulp; testa light to dark brown with strong scent of lemon; raphe not thinckened, slightly darker brown; hilum 4-6 mm long, 2.5-3 mm wide, narrowly elliptic to narrowly ovate.