Infl. of racemes or cymes, often involucrate. Calyx 4-5-toothed; corolla often tubular, 4-5-lobed, often 2-lipped; stamens 4, didynamous. Ovary us. of 2 carpels, 2-5-loculed. Fr. a drupe or schizocarp, often separating into drupelets or nutlets. Some 100 genera, mainly tropical and sub-tropical, with often quadrangular branchlets and us. opp. lvs.

Herbs, shrubs or trees, sometimes lianes, sometimes thorny. Stems generally quadrangular. Lvs usually opposite, rarely whorled or alternate, exstipulate, usually simple, less commonly compound. Infl. racemose and often forming a head, or cymose and then usually dichotomous. Fls ± zygomorphic, usually 5-merous. Calyx (4)-5-(8)-lobed. Corolla 5-lobed, rotate and usually with narrow tube, occasionally campanulate, 2-lipped to nearly regular; lobes imbricate. Stamens usually 4, rarely 5 or 2, didynamous, epipetalous. Ovary superior, usually with 2 but occasionally 4-5 carpels, often divided by a false septum down each carpel. Ovules 2 to each true carpel. Style terminal; stigma usually lobed. Fr. generally a drupe, less commonly a capsule, rarely a schizocarp and each fr. usually dividing into 2 or 4 nutlets. Seed non-endospermic.