previous arrow
next arrow


Tall trees, boles straight, crown dome-shaped or flat. Leaves with prominent parallel nerves on the undersurface, petiole swollen and articulated near lamina base, stipules large, caducous, Flowers on short, few-flowered axillary panicles. Sepals 5, unequal, connate in a tube to form the ovary wall. Petals oblong, contorted. Stamens numerous, connective prolonged into a long point or appendaged. Ovary ovoid to conical, stylopodium cylindrical to filiform. Tube of fruiting calyx with 5 ribs or winged, two of which develop into  large wings. Fruit a nut with greatly enlarged sepals, two of which much longer than the others.

Key to the species

Serial Key Reference
1a. Fruiting calyx tube with 5 protuberances near mouth D. tuberculatus
1b. Fruiting calyx tube with no protuberances near mouth 2
2a. Fruiting calyx tube smooth, never ribbed nor with straight or undulated wings 3
2b. Fruiting calyx tube 5-ribbed or with 5 straight or undulated wings 4
3a. Fully developed leaves glabrous on both surfaces even when young; fruiting calyx tube 2.0-3.5 × 1.5-2.5 cm, ovoid to turbinate, both the tube and longer lobes glabrous D. turbinatus
3b. Fully developed leaves pilose or grey to rufous-pubescent with minute fascicled hairs at least on the midrib and lateral nerves on ventral surface; fruiting calyx tube 1-1.5x 1 -1.3 cm, subglobose, both the tube and longer lobes sprinkled with small, stellate hairs D. gracilis
4a. Fruiting calyx tube 5-ribbed, longer lobes 6.5- 9.5 cm long. Tops of twigs and petioles of young leaves covered with yellowish-brown, long, tawny hairs mixed with stellate indumentum D. costatus
4b. Fruiting calyx tube 5 straight or undulated wings starting between the lobes and running down to base, longer lobes 9 – 14.5 cm long. Midrib and lateral nerves on ventral surface of leaves covered with buff coloured felt of short tangled hair D. alatus