Medicago polymorpha

Medicago polymorpha L., Sp. Pl. 2: 779. 1753; Shin, Rhodora 58: 5. 1956; Ali in Nasir & Ali, Fl. W. Pak. 100: 302. 1977; Sharma & Kachroo, Fl. Jammu 2 (Illustr.): t.67. 1983; Dhaliwal & Sharma, Fl. Kullu Dist. 234. 1999; Kaur & Sharma, Fl. Sirmaur 262. 2004; Singh & Sharma, Fl. Chamba Dist. 282. 2006; Fl. China @ eFloras.org 10: 557; Fl. Pak. @ eFloras.org p. 302; M. denticulata Willd., Sp. Pl. 3: 1414. 1802; Baker in Hook. f., Fl. Brit. Ind. 2: 90. 1879; Collett, Fl. Siml. ed. 2: 120. 1921 (Reprint 1980).

Annual or biennial herbs, 20-90 cm. Stems prostrate or ascending, branched at base, subquadrangular, glabrescent. Leaves pinnately trifoliate; stipules adnate to petiole at base, 4-9 mm, margin irregularly laciniate, segments linear; petioles long and thin, 1-6 cm; leaflets obovate or triangular-obovate, 7-20 cm x 5-15 mm, papery, sparsely hairy abaxially, glabrous adaxially, base broadly cuneate, margin shallowly serrate in approximately 1/2 apical region, apex obtuse, truncate or emarginate, apiculate; rachis and petiole with adaxial canal. Flowers (1 or) 2-10 in axillary racemes, crowded into head, bisexual, zygomorphic, 5-merous, perigynous, ca. 4 mm long, yellow; peduncles slender 3-15 mm long, usually longer than leaves, hairy; bracts ca. 1 mm long, lanceolate, acute; pedicels less than 1 mm. Sepals 5, fused; calyx 2.5-3.9 mm, 5-toothed, subequal, teeth 1-1.5 mm, lanceolate acute, sparsely hairy. Corolla papilionaceous, yellow, 3-4 mm long; vexillum 3.5 mm x 3.0 mm, obovate, emarginate, yellow with brown lines; wings (ca. 3 mm) and keels (ca. 2.5) smaller than vexillum, with hooked appendages. Stamens 10, diadelphous (9+1), anthers uniform. Ovary sessile or shortly stipitate, unilocular, ovules numerous, placentation marginal; style subulate; stigma subcapitate, oblique. Legumes ash green to greenish brown, discoid, 4-6(-10) mm, spirally twisted in 1.5-2.5 or more tight coils and bearing 2 rows of hooked spines along the outer margin, net-veined with radial veins connected near edge on coil face, 4-5 seeds per fruit. Seeds brown, reniform, ca. 2.5 mm x 1.5 mm, smooth.

Flowering and Fruiting: March to May
Common Names: Toothed Bur Clover, Californian Bur Clover, Toothed Medik; Chandausi, Maina (Hindi)