Trees, evergreen or semievergreen, rarely deciduous in dry season. Xylem with aromatic resin in intercellular resin canals. Branchlets with stipular scars, sometimes annular. Leaves simple, alternate; stipules persistent or caducous, large or small; leaf blade with lateral veins pinnate, margin entire or sinuate-crenate. Inflorescences few- or many-flowered, terminal or axillary racemes or panicles; flowers usually sweetly scented; bracts usually fugacious and minute, rarely persistent and large. Inflorescences, calyces, petals, ovary, and other parts usually with stellate, squamate, fascicled or free-standing hairs. Flowers bisexual, actinomorphic, contorted. Calyx lobes 5, free or united at base, imbricate in bud if not united. Petals 5, adnate or connate at base. Stamens (10-)15 to many, free from or connate to petals; filaments usually dilated at base; anthers 2-celled, with 2 pollen sacs per cell (Chinese species); connective appendages aristate, filiform or stout. Ovary superior, rarely semi-inferior, slightly immersed in torus, usually 3-loculed, each locule 2-, rarely many ovuled; ovules pendulous, lateral or anatropous. Fruit usually nutlike, sometimes capsular and 3-valved, 1(to many)-seeded, with persistent, variously accrescent calyx of which 2 or more lobes are usually developed into lorate wings. Seed exalbuminous; cotyledons fleshy, equal or unequal, applanate or ± folded or cerebriform, entire or laciniate; radicle directed toward hilum, usually included between cotyledons.

Tong Shaoquan & Tao Gouda. 1990. Dipterocarpaceae. In: Li Hsiwen, ed., Fl. Reipubl. Popularis Sin. 50(2): 113-131.

About 17 genera and 550 species: tropical Africa, Asia, and South America (in Asia, most species and genera in NW Borneo); five genera and 12 species (one endemic, one introduced) in China.

(Authors: Li Xiwen (李锡文 Li Hsi-wen), Li Jie (李捷); Peter S. Ashton)