Description from
Flora of China
Hedysarum vespertilionis Linnaeus f., Suppl. Pl. 331. 1782; Lourea vespertilionis (Linnaeus f.) Desvaux.
Herbs, perennial, erect, 60-120 cm tall. Leaves usually 1-foliolate, rarely 3-foliolate; petiole 2-2.5 cm, pilose; terminal leaflet blade rhombic or narrowly rhombic, 0.8-1.5 × 5-9 cm, base slightly cordate, apex broad and truncate or slightly emarginate; lateral ones obcordate or obtriangular, usually inequilateral, 0.8-1.5 × 1.5-2 cm, lateral veins 3 or 4 on each side of midvein, abaxially pilose, adaxially glabrous, base cuneate or nearly rounded, apex truncate. Inflorescences 5-15 cm, pubescent. Pedicel 2-4 mm, gray pubescent. Calyx half-hyaline, accrescent, 0.8-1.2 cm, reticulate veined, pubescent; lobes triangular, ca. as long as tube, upper 2 slightly connate. Corolla yellowish white, not exserted, ca. 6 mm. Legume 4- or 5-jointed; articles blackish brown at maturity, ca. 3 × 2 mm, reticulate veined, glabrous, wholly enclosed by calyx. Fl. Mar-May, fl. Oct-Dec.
The whole plant is used medicinally for treating tuberculosis and snake bites. The leaves are used as a topical treatment for healing bone fractures.
Open grasslands, thickets, roadsides, seasides. Guangdong, Guangxi, Hainan [widespread in all tropical regions].