三叉刺 san cha ci

Desmodium horridum Steenis; D. unifoliolatum (Merrill) Steenis.

Shrubs, 1-2 m tall. Spines 3-5 cm. Leaves alternate; peti­ole 2-4 mm, pubescent; blade elliptic or oblong-elliptic to lin­ear-oblong, 1.5-6 × 0.7-1.5 cm, nearly leathery, distinctly reticulate veined, both surfaces glabrous, apex rounded, mucro­nate, sometimes emarginate. Racemes ca. 3 cm, sparsely pilose; bracts numerous around base of rachis, striate. Pedicels ca. 5 mm, often fascicled at node of rachis. Flowers ca. 1 cm. Calyx ca. 3 mm, sparsely pubescent; upper lobe triangular-ovate. Ovary slightly pubescent; style glabrous. Legume stalked, straight, flat and thin, (2-)3-4 cm, pubescent, reticulate veined; lower suture indented, upper suture straight or slightly undulate; articles 6-7 × ca. 4 mm, lateral surfaces reticulate veined. Fl. Apr-Jul, fr. Sep-Oct.

Dry thickets of savannas, sparse forests of riverbanks; ca. 200 m. Hainan [Indonesia (Lesser Sunda Islands), Philippines, Vietnam].