巨序楼梯草 ju xu lou ti cao

Elatostema mollifolium W. T. Wang.

Herbs perennial, dioecious, 50-100 cm tall. Stems erect, simple, glabrous. Leaves alternate; nanophylls absent; stipules lanceolate or broadly lanceolate, 10-18 × 2.5-3 mm, glabrous, with cystoliths; petiole 1.5-12 mm; leaf blade obliquely elliptic, 9-25 × 3.5-10 cm, nearly papery or herbaceous, major basal lateral veins asymmetric, 1 basal, the other arising above base, abaxial surface glabrous or sparsely puberulent along nerves, adaxial surface sparsely hirtellous, cystoliths conspicuous, dense; base with broader half broadly cuneate, margin denticulate, apex acuminate. Male inflorescences solitary, simple, 10-25 mm in diam.; peduncle 5-7 mm; receptacle 8-23 mm in diam.; bracts connate, ca. 5 mm wide; bracteoles cymbiform-linear. Female inflorescences solitary, 15-25 × 10-20 mm; peduncle ca. 5 mm; receptacle oblong, 14-23 × 9-18 mm; bracts triangular; bracteoles spatulate-linear. Male flowers 4-merous. Achenes ellipsoid, 8-ribbed. Fl. Feb-May.

Evergreen broad-leaved forests in ravines; 1000-2000 m. C and S Yunnan [Malaysia, Thailand].