Trees or shrubs usually with bitter bark. Leaves alternate, sometimes opposite, pinnate to unifoliolate or rarely simple; stipules present or absent. Inflorescences axillary, racemose, paniculate, cymose, rarely spicate. Flowers generally small, bisexual or unisexual (andromonoecious, functionally dioecious, or distinctly dioecious), often with rudiments of opposite sex, actinomorphic. Calyx of 4 or 5(-8) sepals, imbricate or valvate. Petals usually 4 or 5(-8), free, imbricate or valvate. Stamens same number as petals and alternate with them, or 2 × as many as petals (or more); filaments free, base often with an appendage; anthers oblong, versatile, bicelled, with a longitudinal slit. Disk usually present, sometimes a gynophore or androgynophore. Gynoecium weakly united at base, or virtually free, usually 2-5-carpellate; ovary superior, with axile placentation; ovules 1 or 2 per locule, apical or basal; style connate or free; stigmas 2-5. Fruit a "drupe" or "samara," actually 1-5 fruitlike monocarps produced per flower, each a druparium or a samarium; endosperm present or absent; embryo straight or curved, with thick cotyledons.

Harrisonia R. Brown ex A. Jussieu and Suriana Linnaeus, treated in the Simaroubaceae in FRPS (43(3): 13-15. 1997), are treated in the Cneoraceae and the Surianaceae, respectively, in this volume.

Chen Pangyu. 1997. Simaroubaceae (excluding Harrisonia and Suriana). In: Chen Shukun, ed., Fl. Reipubl. Popularis Sin. 43(3): 1-16.

Twenty genera and ca. 95 species: mainly in tropical and subtropical regions, some species in temperate regions; three genera and ten species (six endemic) in China.

(Authors: Peng Hua (彭华); Wm. Wayt Thomas)