Tree 5–15 m tall, with a palm-like habit, associated with ants, the branches often hollow and swollen with access pores present; young branches distinctly square in cross section, often slightly winged on the angles, glabrous to pubescent.Leaf blades 9.5–22(30) × 4.5–16.5 cm, oblong to ovate or sometimes broadly ovate, shortly acuminate at apex, obtuse to rounded or truncate to subcordate at base, glabrous or sometimes sparsely pubescent on upper surface, glabrous or pubescent on nerves or sometimes sparsely pubescent beneath, papery to subcoriaceous; lateral nerves in 7–10 main pairs; tertiary nerves moderately conspicuous beneath; domatia present as hair-lined cavities in the axils of lateral and sometimes tertiary nerves; petioles 10–15 mm long, glabrous or pubescent; stipules 4–10 mm long (or 14–18 mm long on saplings or coppice growth), narrowly ovate to ovate-caducous.Flowers with a very unpleasant smell, 5-merous, borne in 80–120-flowered, dichotomous corymbose pedunculate cymes; true peduncle rather short, the portion above the bract being longer, 0.8–2(4) cm long altogether, pubescent or glabrous; pedicels 1.5–2.5 mm long, sparsely puberulous to pubescent; bracts 1–4 mm long, in connate pairs or sometimes free; bracteoles free, inconspicuous, or conspicuous and up to 3 mm long.Calyx tube c. 1 mm long, glabrous or sometimes pubescent towards the base; limb 0.5–1 mm long, truncate to dentate, ciliate, puberulous inside.Corolla white or creamy-yellow; tube 2–3.5 mm long, with a ring of deflexed hairs set above mid-point inside; lobes 2.5 × 1.25–1.5 mm, oblong ovate, acute.Anthers not persistent in mature flowers.Style 5–7 mm long; pollen presenter 1.5–2 mm long, ribbed; disk pubescent or sometimes glabrous.Fruit 6–8 × 9–12(14) mm, usually rather prominent at apex, black or greyish-black.Pyrenes 6–8 × 4.5–6 × 3–4 mm, strongly curved, with a groove from point of attachment to the centre of the lateral face, with a shallow crest at the apex, cartilaginous, scarcely rugulose.
