深紫楼梯草 shen zi lou ti cao

Herbs perennial, dioecious, 70-80 cm tall, glabrous. Stems ascending or erect, branched. Leaves alternate; nanophylls absent; stipules triangular, ca. 2 × 1.5 mm; petiole 5-8 mm; leaf blade elliptic or oblong, 17-23 × 4.5-7.5 cm, herbaceous, major basal lateral veins absent and venation pinnate, cystoliths conspicuous, dense; base obliquely cuneate, margin crenate-dentate, apex caudate-acuminate. Male inflorescences solitary, ca. 2.6 mm in diam.; peduncle 10-15 mm; receptacle ca. 25 mm in diam.; bracteoles linear. Female inflorescences solitary or in pairs, nearly orbicular, 4-9 mm in diam., sessile; receptacle nearly orbicular, 4-7 mm in diam.; bracts triangular; bracteoles subulate. Male flowers 5-merous. Achenes ellipsoid, 8-ribbed. Fl. Apr.

Evergreen broad-leaved forests in ravines; ca. 1400 m. SE Yunnan [N Vietnam].