Herbs prostrate, ± stoloniferous. Stems longitudinally ridged and sulcate. Leaves: stipules membranous, base enlarged and clasping, slender; petioles nearly as long as or longer than leaf blades, papery, subglabrous, ± glandular, margin entire or inconspicuously crenulate; veins 5-7, basal. Inflorescence a terminal spike, with large, white, leafy involucral bracts at base or not; rachis compressed, both sides broadly ridged or nearly winged, subglabrous. Flowers white, small. Stamens (5 or)6(or 7), nearly on apex of ovary, shorter than styles; filaments ca. as long as to slightly longer than anthers; anthers oblong. Pistils 4, (2-)4-carpelled; carpels connate; ovary semi-inferior, 1-loculed; placentae 4, each with 9-13 ovules; styles 4, recurved. Capsule fusiform, dehiscent at apex.

Two species: C and SW China, N Vietnam; two species (one endemic) in China.