Gonystylus bancanus (Miq.) Kurz

Tree, 18-42 m by 30-120 cm, with many knee-roots (pneumatophores). Branchlets blackish-grey, much branched and 'twiggy'. Leaves elliptic, shortly oblong-oblanceolate or obovate, 4-14½ by 2-7 cm, base broadly cuneate to rounded, apex rounded and shortly acuminate-cuspidate, firmly coriaceous, often conduplicate, margins somewhat undulate and markedly reflexed, quite glabrous, mostly drying a characteristic dull purplish ('plum') colour below and ± chestnut or ochraceous above, appearing rather smooth, but under a lens minutely shagreened; midrib narrowly and deeply channelled above; nervation less conspicuous than in most species, moderately close above, rather lax and not sharply prominent below; petiole 8-18 by 1-2 mm, glabrous. Inflorescences (apparently rarely produced) subsimple, up to 9 cm long, minutely adpressedly ochraceo-puberulous. Pedicels up to 1½ cm, puberulous. Calyx shortly cupular, 5 mm long, 5-6 mm wide; sepals deltoid, 2-3 mm long, subacute. Petals 13-20, narrow-lanceolate, acuminate, 3 mm long, glabrous, epustulate. Style rather robust, much contorted, glabrous; stigma rather large, capitate. Fruit subglobose, 3-valved, valves orbicular-ovate, up to 4 cm long by 3½ cm wide, 3 mm thick, minutely roughened but not rugose. Seeds flattened-ovoid, 28 by 22 by 6 mm.

Lowland freshwater coastal swamps ('peat forests') (? on sandy soil), mostly subject to periodic inundation, but also in non-inundated areas, up to 100 m, sometimes forming pure stands (e.g. Rejang delta, Sarawak); occasionally in inland swamps (Selangor); fl. Feb.-March (buds also noted in May and Oct.), fr. May-June.

Uses. Timber, for planks, barrels, boxes, etc.; cf. THOMAS Mal. For. 12 1949 206 . Heartwood used for incense; cf. HEYNE Nutt. Pl. Ned. Ind. 3 1917 183 . Inner bark contains numerous fine, brittle fibres, which break off and irritate the skin.

Can be grown by seedlings. Seeds needs soaking.