Shrub or small tree, 2–5 m high; branchlets sparsely silky pubescent or glabrous. Leaves flat, narrow-elliptic to lanceolate, 5–15 cm long, 5–20(–27) mm wide, apex usually acute; venation obscure; lateral veins at acute angles. Inflorescence 16–28-flowered; rachis 1–1.5 mm long; pedicels 4.5–7 mm long, glabrous; perianth 2–4.5 mm long, white, glabrous; pistil 6–6.5 mm long; pollen presenter an oblique disc. Fruit obliquely ovate to ± globose, c. 2–3.5 cm long, 1–3 cm wide, black-warted; horns often obscure; seed not occupying whole valve face, 1.7–2 cm long; wing only partly down one side of seed body. Flowers Aug.–Nov.