Terrestrial or epiphytic, caulescent, erect, ascending, or scrambling herbs, subshrubs, or lianas, without modified stems. Stems branched or unbranched. Leaves opposite, often appearing rosulate, equal to strongly unequal in a pair, venation pinnate, foliar nectaries absent. Flowers axillary, in pedunculate or epedunculate, usually congested cymes; bracteoles present; pedicellate. Calyx lobes free; corolla white or yellow with red or purple spots or lines, funnel-form or trumpet shaped; stamens included, filaments not connate or basally connate, anthers coherent, dehiscing by longitudinal slits, thecae parallel or divergent at base; staminode small; disc of 1 or 2 glands; ovary superior, stigma capitate, stomatomorphic, or 2-lobed. Fruit a fleshy, white or colored capsule, loculicidally dehiscent, 2-valved, valves opening slightly.
C and northern S America present, Guianas present
36 or more species, in C and northern S America; 7 species in the Guianas.