Thysanus Loureiro.

Lianas or ± scandent shrubs, rarely small trees. Leaves exstipulate, petiolate, odd-pinnate; leaflets opposite or subalternate, margin entire. Inflorescences terminal or axillary, solitary or fascicled, terminal one usually paniculate, axillary ones racemose and often borne in axils of fallen leaves on old branches; bracts minute, scalelike or lanceolate. Flowers bisexual. Sepals 5, imbricate or valvate in bud, sometimes petaloid, slightly connate at base. Petals 5, slightly shorter than or equaling sepals, connate at base, emarginate and incurved at apex. Stamens ca. 10, free, all fertile, alternately longer and shorter, those opposite sepals usually longer; filaments free or slightly connate at base. Carpels 5, free; ovary pubescent; ovules 2, erect, collateral. Style longer than ovary; stigma capitate. Follicles 1–5, sessile, pyriform, usually elongated into hornlike processes, dehiscing by a longitudinal, adaxial slit, densely tomentose abaxially, appressed hirsute adaxially; persistent sepals not enlarged. Seed 1, mostly black or dark brown, glossy, flattened; aril basal, oblique; endosperm present.

Between 13 and 40 species: mainly in tropical Africa and Madagascar, extending to SE Asia; one species in China.