Kokoona reflexa (Laws.) Ding Hou, Fl. Mal. I, 6 (1962)

Synonyms
Hippocratea maingayi Laws. in Hook.f.
Lophopetalum reflexum Laws. in Hook.f.

Diagnostics
Emergent tree up to 62 m tall and 170 cm dbh. Stipules small. Leaves opposite, simple, penni-veined, often with toothed margin. Flowers ca. 5.5 mm in diameter, white-yellow, placed in panicles. Fruits ca. 117 mm long, brownish, dehiscent capsule containing several wind dispersed winged seeds.

Description
A tree up to 48(-62) m by 90(-170) cm diameter, sometimes with buttresses up to 1.5 m high and c. 0.5 m over the ground. Leaves chartaceous, elliptic-oblong, 5.5-11 by 2.5-4 cm; base cuneate; apex acuminate; margins remotely crenulate, rarely subentire. slightly recurved; nerves 5 pairs; petiole 0.8-1.5 cm. Panicles 2-18 cm long, axillary as well as extra-axillary. Peduncle up to 5.5 cm. Pedicel c. 1 mm. Flowers light green, or dirty yellowish white. Calyx lobes c. 1.3 by 0.5 mm. Petals broadovate, or broad-elliptic, 3 by 2.5 mm. Stamens 1 by 0.8 mm; filaments terete, thin; anthers oblong, 1 by 0.8 mm, obtuse at the apex, connective not produced. Pistil c. 1.5 mm long; ovary gradually narrowed into an obscure style; ovules 10 in each cell; stigma orbicular, flat. Fruits c. 12 cm long; valves c. 3 cm wide. Seeds including the wing 9-11 by 2.5 cm. [from Flora Malesiana]

Ecology
In undisturbed mixed dipterocarp forests up to 800 m altitude. Mostly on hillsides and ridges with sandy soils, but also along rivers and on clay soils.

Distribution
Thailand, Peninsular Malaysia, Sumatra, Borneo.

Local names
Borneo: Bajan, Bajau, Barjau, Batu bagalang, Bintan, Kayu minyak, Sabong api.
Sumatra: Useu-useu, Uding, Kempas sakam, Negris hitam, Negris pinang, Sepalis, Resak, Sajap.