Diodia 鈕扣草屬
型態特徵
Annual or perennial herbs; stems erect or scrambling, sometimes suffrutescent at base. Leaves opposite, penninerved, subsessile or short petiolate; stipules interpetiolar, entire, adnate at base of petioles, forming a sheath. Flowers 1–8 in axillary fascicles, bisexual; calyx tubular-funnelform, deeply divided, lobes 2–6, persistent, at base with bracts divided into lobes; corolla funnelform, white; lobes 4, valvate, hairy on upper inside; stamens 4, inserted in throat, filaments glabrous; ovary 2–4-celled, ovule 1 per cell, style filiform, exserted, stigma broadly 2-lobed; fruit indehiscent, two 1-seeded cocci, with prominent ridges; seeds angular, reticulate.
About 30 species, native to warm temperate to tropical America; 1 species naturalized in Taiwan.
