Baccaurea sumatrana (Miq.) Mull.Arg., in DC. Prodr. 15, 2 (1866)

Latin for 'from Sumatra'.

Synonyms
Baccaurea bivalvis Merr.
Baccaurea kingii Gage
Calyptroon sumatranum Miq.

Description
Tree (4-)15-22 m high, dbh (5-)15-35 cm, buttresses if present up to 1 m high, c. 6 cm thick; branches glabrous, young shoots dark brown to black, Terminalia branching pattern well-developed. Indumentum of simple hairs. Bark greyish-brown to brown to black, 2-16 mm thick, smooth to rather rough, hard, glabrous, peeling off with longitu-dinal flakes of c. 1 cm long, raised glands present, (exudate watery, red); inner bark white to red brown to pink, 1.5-2 mm thick, glabrous, hard, scaly. Heartwood reddish to dark brown. Leaves: petiole 5-48 mm long, glabrous; stipules 1-7 by c. 1 mm, sparsely hairy on both sides, densely hairy at midrib outside, margin not ciliate; lamina ovate to sometimes obovate, 3-19 by 1.2-7.5 cm, l/w ratio 1.1-2.9(-3.75), papery; base attenuate to cuneate (to rounded); apex obtuse to acuminate, up to 18 mm long; upper surface glabrous, rarely granulate, a few discoid glands rarely present; lower surface glabrous, a few discoid glands present; green to red when dry, red when young; secondary veins, 5-8(-10) per side, sometimes closed at margin; nervation reticulate. Staminate inflorescences axillary to somewhat ramiflorous, solitary (to 3 clustered together), up to 2.3(-5.4) cm long, densely hairy, 30-75-flowered, flowers grouped at upper part of inflorescence; branchlets spatulate, 2-3.8 mm long, densely hairy, with (2 or) 3 (or 4) flowers; bracts 1 per branchlet, c. 1 mm long, glabrous outside. Staminate flowers sessile, 0.9-1.8 mm diam., yellow-green; sepals 3-5, each with a different size and shape, 0.3-1.2 by 0.3-1 mm, glabrous; stamens 4-6, 0.4-1 mm long, glabrous; ?laments 0.4-0.9 mm long; anthers 0.1-0.15 mm; pistillode ligulate, up to 0.5 mm high, densely hairy. Pistillate inflorescences axillary to ramiflorous, solitary (to 4 clustered together), 0.7-6.5(-9) cm long, 1-2 mm thick, densely hairy except at base, 2-20-flowered; pedicel geniculate (90กใ bent) at the abscission zone, 2.2-2.5 mm long, upper part c. 1.2 mm, densely hairy; bracts absent. Pistillate flowers 1.5-2 mm; sepals 4 or 5, ovate to obovate, each with a different size and shape, 0.5-1.3 by 0.5-1.4 mm, densely hairy on both sides; ovary cylindrical, 1.8-2.5 by 1-1.4 mm, 2-locular, sparsely hairy to velutinous; style absent or up to 0.1 mm long; stigmas not lobed to apically lobed up to the base, lobes up to 0.5 mm long, glabrous. Fruits ellipsoid, laterally flattened, usually 1-seeded, fleshy capsules, 9-17 by 4-10 mm, dehiscing loculicidally, outside subglabrous, inside glabrous, septa rarely sparsely hairy, yellow to orange to reddish; pedicel straight, 2-8 mm long, upper part 0.5-2 mm; pericarp c. 1 mm thick; column often persistent, 6-12 mm long, curved, flattened; sepals persistent, small. Seeds ellipsoid, laterally flattened, 6-9 by 4-7.5 by 2-4 mm; arillode orange; testa red; cotyledons 3.5-6 by 4-6.5 mm, thin; radicle up to 0.8 mm long. [from Flora Malesiana]

Ecology
In undisturbed to slightly disturbed mixed dipterocarp to sub-montane forests, and sometimes in keranga forest up to 1600 m altitude. Mostly on hillsides and ridges with sandy to clay soils, sometimes also on limestone.

Uses
The timber is used.

Distribution
Peninsular Thailand, Peninsular Malaysia, Sumatra, Java, Borneo.

Local names
Borneo Bidu-bidu, Kayu masam, Kelibon, Perepat, Puak purut, Puak ukang, Sangkurat.
Peninsular Malaysia Tampoi.
Sumatra Ketjipot, semasam, semasam pris. Bangka: Masput (Malay). Simeulue Island: Toetoen bolawak iteung pajo, toetoen bolawah kehe-pajo.