扭曲山蚂蝗 niu qu shan ma huang

Hedysarum intortum Miller, Gard. Dict., ed. 8, Hedysarum no. 11. 1768; Desmodium nantouense Y. C. Liu & F. Y. Lu.

Herbs, perennial, scandent, to 3 m. Stems triangular, with white spongy pith, densely yellowish uncinate hispid and pilose or sometimes nearly glabrous. Leaves 3-foliolate; stipules ovate, 4-12 mm, acuminate or caudate, often persistent; petiole 3-9 cm, hairy as stems; terminal leaflet blade ovate or sometimes broadly elliptic, 5-13 × 2-7 cm, papery, both surfaces ap­pressed pilose, base rounded to truncate, apex acute. Racemes terminal or axillary, to 30 cm; rachis with dense appressed to spreading hooked hairs, 2-flowered at each node. Pedicel fili­form, 6-10 mm. Calyx 2.5-3 mm, 5-parted; lowest lobe longest. Corolla purplish red to violet becoming bluish or greenish white, 9-11 mm. Legume shortly stipitate, narrowly oblong, 2-4.5 cm × 3-4 mm, densely brownish hooked hairy, 5-10-jointed, lower suture deeply constricted, upper suture thickened, slightly sinuate; stipe ca. 2 mm; articles semicircular or rhom­bic, 4-5 mm. Fl. Jul-Oct, fr. Oct-Nov. 2n = 22, 24.

100-1400 m. Introduced in Taiwan [native to Central and South America].