Shorea balangeran (Korth.) Burck, Ann. Jard. Bot. Btzg. 6 (1887)

Named after the local name for this species.

Synonyms
Hopea balangeran Korth.
Parahopea balangeran Heim
Parashorea balangeran Merr.
Shorea balangeran var. angustifolia Boerl.

Diagnostics
Mid-canopy tree up to 32 m tall and 75 cm dbh. Stem with resin. Stipules up to ca. 7 mm long. Leaves alternate, simple, penni-veined, glabrous. Flowers ca. 10 mm in diameter, yellowish, placed in panicles. Fruits ca. 6 mm long, green-red, with three up to ca. 50 mm long wings, wind dispersed.

Description
Large buttressed tree. Twig, leaf bud. stipule, petiole, midrib and nerves beneath, panicle and calyx outside shortly densely persistently red-brown puberulent: leaves beneath cream lepidote: nut apex sparsely puberulent. Twigs c. 2 mm diameter apically, slender, terete, smooth. Buds 5 by 3 mm, ovoid, acute; stipule to 7 by 4 mm, ovate, acute. Leaves 7-18 by 3-8 cm, oblong-elliptic to lanceolate, coriaceous, conspicuously cream beneath: base broadly cuneate to obtuse: acumen to 1.5 cm long, slender, tapering: nerves 13-18 pairs, slender, barely elevated beneath, evident above, at 45-55 degrees: tertiary nerves densely scalariform, obscure: midrib slender but prominent beneath, obscurely depressed above: petioles 2-3 cm long, slender. Panicle to 8 cm long, slender, terminal or axillary: doubly branched, branchlets to 3 cm long, with to 7 secund flowers. Flower buds to 6 by 3 mm, fusiform: 3 outer sepals narrowly lanceolate, subacute: 2 inner short, ovoid, prominently acuminate. Stamens 15, shorter than style at anthesis: filaments compressed at base, gradually tapering and filiform below the broadly ovoid anthers; appendages very slender, glabrous, twice length of anthers; ovary ovoid, puberulent: style columnar, c. 1.5x length of ovary, puberulent towards base, not trifid. Fruit pedicel short, slender, 3 longer calyx lobes to 50 by 7 mm, spatulate, obtuse, c. 2 mm broad above the to 4 by 3 mm ovate saccate thickened base: 2 shorter lobes to 15 by 2 mm, linear, similar at base. Nut to 6 by 4 mm, ovoid, apiculate. [from Flora Malesiana]

Ecology
In undisturbed keranga or (peat)-swamp forests near the coast up to 100 m altitude. Mostly on poor sandy soils on alluvial sites or hillsides.

Uses
The timber is used.

Distribution
Sumatra, Borneo.

Local names
Borneo: Balangiran, Kahoi, Kawi, Kelandan, Kelansau, Lempung nasi, Tomi.
Sumatra: Malangsir (Bangka).