20. Pilea aquarum Dunn, J. Linn. Soc., Bot. 38: 366. 1908.
湿生冷水花 shi sheng leng shui hua
Herbs perennial, stoloniferous, sometimes puberulent, dioecious or sometimes monoecious. Stems often reddish, simple or few branched, 10-70 cm tall, succulent, with galls on mid portion of internodes. pubescent or glabrous, Stipules persistent, subcordate, 3-5 mm, membranous, acute at apex, veiness; petioles subequal or unequal in length, 0.5-3.5 cm, pubescent or glabrous; leaf blade abaxially pale green, adaxially dark green, lustrous, broadly elliptic or ovate-elliptic, sometimes lanceolate, subequal or unequal in size, 1.5-14 × 1-7 cm, membranous, 3-veined, prominent adaxially, lateral veins several, subtransverse, inconspicuous, both surfaces pubescent or glabrous, base broadly cuneate or obtuse, sometimes oblique, margin obtusely crenate, crenate-serrate, or coarsely dentate, apex acute, obtuse, or acuminate. Inflorescences solitary; male inflorescence a cymose panicle, 2-7 cm overall, peduncle 1.5-3.5 cm; female cymes dichotomously branched, compacted into clusters, pedunculate or subsessile. Male flowers pedicellate, in bud ca. 2 mm; perianth lobes 4, elliptic, subapically corniculate; stamens 4; rudimentary ovary small. Female flowers subsessile; perianth lobes connate at base, unequal, abaxial lobe cymbiform, longer, subapically corniculate; staminodes 3, scale-like, oblong. Achene greenish brown, obliquely ovoid, ca. 0.7 mm, slightly compressed, verrucose. Fl. (Nov-)Feb-May, fr. (Mar-) May-Jun.
Wet places along ditches or streams; 200-2600 m. Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Jiangxi, SE Sichuan, Taiwan, SE Yunnan [Japan, Vietnam].