Hopea nervosa King, J. R. As. Soc. Beng. Sc. 62, 2 (1893)

Diagnostics
Upper canopy tree up to 45 m tall and 75 cm dbh. Stem with resin. Stipules up to ca. 2 mm long. Leaves alternate, simple, penni-veined, with conspicuous, widely spaced secondary veins. Flowers ca. 4.5 mm in diameter, white-yellowish-pink, placed in panicles. Fruits ca. 8 mm long, green-yellow-pink-red, with two ca. 65 mm long wings, wind dispersed.

Description
Medium-sized tree. Twig, leaf bud, stipule, panicle, petiole and midrib on both surfaces puberulent, glabrescent. Twig to 1 mm apically, slender, becoming smooth, glabrous. Bud to 2 by 1 mm, ovoid, acute. Stipule to 2 mm long, narrowly oblong, acute. Leaves 9-18 by 4-7 cm, thinly coriaceous, narrowly ovate to lanceolate; base broadly cuneate; acumen to 1.4 cm long, narrow; nervation scalariform, nerves 13-15 pairs, dense, slender, prominent beneath, slightly curved, at 40-60 degrees with or without short slender secondaries; tertiary nerves dense, slender, scalariform, slightly sinuate, diagonal to nerves; midrib slender, prominent beneath, slightly depressed above; petiole 1-1.2 cm long. Panicle to 9 cm long, terminal or axillary, to 2-axillary, terete; singly branched, branchlets to 1.5 cm long, bearing to 5 flowers; bracteoles small, ovate, acute, puberulent outside, glabrous within. Flower bud to 3 mm long, subglobose. Petals narrowly oblong, densely tomentose on parts exposed in bud, purple with pale tips. Stamens 15; filaments of inner 2 rows broad at base, abruptly tapering, 5 outer filaments slender: anthers subglobose; appendage to connective slender, c. 2 times length of anther. Ovary and stylopodium broadly cylindrical, truncate, glabrous; style short. Fruit subsessile. Calyx glabrous, impressed at base; 2 longer lobes to 12 by 1.8 cm, thinly coriaceous, spatulate, narrowly obtuse, to 2.5 mm broad above the to 13 by 8 mm broadly ovate saccate thickened base; 3 shorter lobes to 1.5 cm long, acute, similar at base, closely adpressed to nut. Nut to 1 cm long and diameter, ovoid, style remnant short. [from Flora Malesiana]

Ecology
In undisturbed mixed dipterocarp forests up to 700 m altitude. Usually on hillsides and ridges, but also in alluvial sites. On rather rich clay to sandy soils.

Uses
The timber is used.

Distribution
Peninsular Malaysia, Borneo.

Local names
Borneo: Damar jankar, Gamogamod, Luis, Merawan, Mersiau, Selangan, Selangan batu bertunjang, Selangan batunjang, Selangan puteh.
Malaysia: Merawan jangkang, Merawan penak, Chengal rawan, Chengal pasir.