华南楼梯草 hua nan lou ti cao

Elatostema platyphyllum var. balansae (Gagnepain) Yahara.

Herbs perennial, dioecious, 20-40(-80) cm tall. Stems ascending or erect, simple or branched, glabrous or pubescent. Leaves alternate; nanophylls absent; stipules lanceolate, 5-14 × 3-4 mm, strigillose, without cystoliths; petiole 0-2 mm; leaf blade obliquely elliptic to oblong, 6-17 × 3-6 cm, herbaceous, major basal lateral veins both arising at base of leaf blade or 1 arising above base, abaxial surface sparsely puberulent or glabrous, adaxial surface sparsely strigillose, cystoliths conspicuous, dense; base with broader half broadly cuneate or rounded, margin dentate, apex cuspidate or acuminate. Male inflorescences solitary, simple, 8-9 × 4-7 mm; peduncle 1-2 mm; receptacle 6-7 mm in diam.; bracts connate, 2.5-3 mm; bracteoles linear. Female inflorescences solitary or in pairs, 5-10 mm in diam.; peduncle 0-2 mm; receptacle 3-9 mm in diam.; bracts triangular; bracteoles spatulate-linear. Achenes ellipsoid, 8-ribbed. Fl. Apr-Jun.

Valley forests, shaded wet places along streamsides; 300-2400 m. N Guangdong, NW Guangxi, S Guizhou, NW Hunan, SW Sichuan, SE Xizang, SE Yunnan [Malaysia, Thailand, N Vietnam].