光疣冷水花 guang liu leng shui hua

Herbs perennial or subshrubs, glabrous, dioecious. Stems black when dry, much branched, terete, to 100 cm tall, woody at base; stems and stipules densely covered with cystoliths. Stipules deciduous, green, oblong, 6-7 mm, papery, longitudinally 2-ribbed; petiole unequal in length, 0.7-2.7 cm; leaf blade abaxially pale green, adaxially dark green, ovate to lanceolate, slightly oblique, subequal in size, 2.5-10 × 1.2-3.5 cm, papery, 3-veined, lateral veins 10 each side, transverse secondary veins anastomosing by margin, both surfaces lustrous, base rounded or subcordate, margin crenate-serrate from base, apex acuminate or shortly caudate-acuminate. Inflorescences in pairs, male inflorescence a cyme, dichotomously branched 4-6 times, ca. 1-2 cm; female ones dichotomously branched 3 times, ca. 1 cm; bracts ovate, ca. 0.6 mm. Male flowers shortly pedicellate, in bud obovoid, ca. 1.4 mm; perianth lobes 4, reddish, oblong-ovate, connate 1/2 of length, subapically corniculate; stamens 4; rudimentary ovary conic, ca. 0.3 mm. Female flowers shortly pedicellate; perianth lobes triangular-ovate; staminodes oblong. Achene oblong-ovoid, ca. 1.2 mm, slightly compressed, sparsely tuberculate, persistent perianth lobes 3 times shorter than achene. Fl. Jan-Apr, fr. Apr-May.

Shaded wet places in forests in limestone mountains; 1100-1300 m. W Guangxi, SE Yunnan (Xichou) [Vietnam].