早花苜蓿 zao hua mu xu

Annual herbs, (5-)10-20(-50) cm. Stems prostrate or as­cending, quadrangular, branched at base, sparsely hairy. Stip­ules ovate, incised or lacerate; leaflets obovate or obcordate, (2-)4-8(-12) × (2-)5-9(-13) mm, papery, sparsely hairy abaxi­ally, glabrous adaxially, base broadly cuneate, margin only ob­scurely serrate apically, apex truncate or emarginate. Flowers 1 or 2 in axillary umbel; peduncles shorter than petiole, bracts ca. 1.5 mm; pedicels less than 1 mm. Corolla yellow, 3-4 mm; standard broadly orbicular. Ovary linear. Legume usually only 1 per umbel, scarlet to dark brown, discoid, 3-4 mm, loosely coiled in 2-4(or 5) spirals, coil edge wide, deeply grooved, spines 10 in each row. Seed brown, reniform, 2-2.8 × 1-1.3 mm. Fl. Mar-Apr, fr. May-Jul.

Introduced and cultivated. Anhui, Fujian, Guangxi, Guizhou, Hai­nan, Hubei, Hunan, Jiangsu, Sichuan [native to the N Mediterranean region].