Shrubs, often armed with shoots modified into spines. Leaves entire, sometimes verticillate. Flowers 1-6 in number, axillary, white to light purple. Calyx persistent, tubular to ± campanulate, 4-5-lobed, irregular; lobes small, acute to obtuse, shorter or equalling the corolla tube, rarely more, acute or obtuse. Anthers included or exserted, dehiscing longitudinally; filaments glabrous or pilose to villous. Ovary bilocular. Style slender, stigma capitate. Berry globose or oblong, red or black. Seeds reniform, compressed, subglabrous.