Description from Flora of China
Piper pellucidum Linnaeus, Sp. Pl. 1: 30. 1753.
Herbs annual, fleshy, 20-40 cm high, all parts glabrous. Stems erect or ascending, branched, glabrous. Petiole 1-2 cm; leaf blade broadly ovate or ovate-triangular, length ± equal to
width, 1-3.5 cm, membranous, both surfaces glabrous, translucent, base cordate, apex acute or obtuse; veins 5-7. Spikes terminal or leaf-opposed, slender, 2-6 cm, glabrous, flowers lax;
bracts suborbicular, ca. 0.5 mm wide, stalk short. Anthers sub-
globose. Ovary ellipsoid; stigmas pubescent. Nutlet globose, ca. 0.5 mm in diam. Fl. Apr-Jul.
Wet places within forests, rock crevices, bases of cliffs, sometimes a weed of cultivation; near sea level to 200 m. Fujian, Guangdong, Guangxi, Hainan, Yunnan [native to tropical North and South America].