Monoecious herb, sometimes epiphytic, erect, to 1.5 m high. Leaves opposite on stem, alternate on any branches; petioles 5-25 mm long, sparsely pubescent; blades narrowly ovate or lanceolate, acuminate, rounded to subcordate at base, 4.5-11(18) cm long, 2.5-4 (7) cm wide, serrate-dentate, glabrous or with inconspicuous pubescence on lower surface of veins. Flowers minute, pinkish, in discrete, unisexual, globular clusters along axillary spikes 2-8 cm long and often leafy near the tip; staminate perianth 4-lobed; pistillate perianth 4-toothed, ca 2 mm long, nearly sessile. Achenes +/- round, compressed, ca 1 mm diam, brown. Croat 12691. Uncommon, usually occurring in swampy areas along the shore. Flowers and fruits in the rainy season. Canada south to southeastern Brazil; West Indies. In Panama, known only from tropical moist forest in the Canal Zone and Bocas del Toro.