1 | Inflorescence sessile or subsessile in the leaf axil, or very shortly pedunculate, the peduncle, (or pedicel) generally shorter than the calyx and corolla |
1' | Inflorescence conspicuously pedunculate, peduncle exceeding the calyx and corolla; flowers in racemes |
2 | Petals yellow or yellowish |
2' | Petals purple, crimson, bluish or whitish |
3 | Standard glabrous or shortly papillose on the adaxial (outer) surface |
3' | Standard pilose on the adaxial (outer) surface; pod pilose or pubescent |
4 | Flowers 15-18(-22) mm long; calyx 6-9 mm long; pods 15-18 mm long with 1-3 seeds |
4' | Flowers 17-30 mm long; calyx 10-13 mm long; pods 20-33 mm long with 3-6 seeds |
5 | Flowers 2-3(-5) in a congested raceme or cluster; standard c. 2 cm long; calyx-teeth subequal |
5' | Flowers solitary; standard c. 3 cm long; adaxial calyx-teeth distinctly shorter than the abaxial |
6 | Plants erect or suberect, not sprawling or climbing; stems robust; leaflets broadly oblong, ovate, obovate or elliptical |
6' | Plants sprawling or climbing; stems slender, weak; leaflets narrowly oblong, obovate, elliptical or linear |
7 | Pods 5-6 cm long, papillose-ciliate along the sutures; tendrils usually well developed |
7' | Pods exceeding 6 cm in length, not papillose-ciliate along the sutures; tendrils usually reduced to a short awn |
8 | Standard less than 8 mm long; seeds with a papillose testa |
8' | Standard more than 8 mm long; seeds with a smooth, not papillose, testa |
9 | Calyx-teeth narrowly subulate, 3-8 mm long; stipules often rather large and toothed or laciniate |
9' | Calyx-teeth less than 3 mm long, the 2 adaxial deltoid; stipules small, semi-sagittate |
10 | Leaves 2-4-foliolate; leaflets tapering to apex and base; flowers distinctly pedicellate, or 2(-3) in short pedunculate racemes |
10' | Leaves (2-)4-10-foliolate; leaflets usually with an emarginate apex; flowers subsessile or very shortly pedicellate |
11 | Plant with aerial and underground stems, the latter with apetalous flowers and pallid, c. 10-15 mm long pods |
11' | Plant with aerial stems only, all pods conspicuously longer |
12 | Corolla (8-)10-18 mm long; calyx-teeth shorter than tube |
12' | Corolla 18-30 mm long; calyx-teeth as long as or longer than tube |
13 | Pod 6-8 mm wide, contracted between the seeds; seeds 4-5 mm diam. |
13' | Pod 4.5-6 mm wide, not contracted between the seeds; seeds 3-4.5 mm diam. |
14 | Limb of standard deeply emarginate at apex; leaflets conspicuously truncate or emarginate at apex; flowers solitary |
14' | Limb of standard rounded or shortly emarginate at apex; leaflets obtuse, acute or sometimes obscurely emarginate at apex; flowers sometimes in short, few-flowered racemes |
15 | Leaves generally 6-8-foliolate; leaflets oblong-elliptic, 4-12 x 1.5-3 mm; limb of standard usually somewhat recurved |
15' | Leaves generally 8-14-foliolate; leaflets narrowly oblong, 5-20 x 1-6 mm; limb of standard usually straight, not recurved |
16 | Pods moniliform, strongly constricted between the seeds; plants erect or spreading |
16' | Pods not moniliform, not constricted between the seeds; plants sprawing or climbing |
17 | Leaflets of middle and upper leaves large, 3-6 cm long, often exceeding 1 cm in width |
17' | Leaflets of middle and upper leaves usually less than 3 cm long and 1 cm wide |
18 | Flowers small, less than 8 mm long; petals commonly pale blue or whitish |
18' | Flowers medium or large, more than 8 mm. long, variously coloured |
19 | Pod 18-25 x 6-8 mm, apex shortly rostrate |
19' | Pod 6-14 x 2.5-3-5 mm, blunt or shortly acute at apex, not rostrate |
20 | Pod (1-)2-seeded; leaflets with a truncate or emarginate apex; flowers very small and pale |
20' | Pod 3-8-seeded; leaflets acute or obtuse at apex, not truncate or emarginate |
21 | Calyx-teeth narrowly deltoid, 0.8-1-5 mm long; pod glabrous |
21' | Calyx-teeth narrowly subulate, 2-2.5 mm long; pod usually thinly pubescent |
22 | Racemes 1-5-flowered |
22' | Racemes (2-)5-many-flowered |
23 | Leaflets shortly oblong, obovate or suborbicular, almost as broad as long; petals mauve-blue and white or mauve-blue and yellow |
23' | Leaflets narrowly oblong or oblong-elliptic, more than twice as long as wide |
24 | Pod straight; petals mauve-blue and white |
24' | Pod crescent-shaped (lunate); petals mauve-blue and yellow |
25 | Leaves generally 6-8-foliolate; leaflets oblong-elliptic, 4-12 x 1-3 mm; limb of standard generally recurved |
25' | Leaves generally 8-14-foliolate; leaflets narrowly oblong, 5-20 x 1-6 mm; limb of standard not recurved |
26 | Pods pubescent; inflorescence 3-12(-16)-flowered; calyx distinctly gibbous at base; plant usually perennial |
26' | Pods glabrous |
27 | Perennial with tough woody rootstock; leaves linear or almost subulate; inflorescence (8-)10-30-flowered; calyx scarcely gibbous at base |
27' | Annual; leaves narrowly oblong, apex rounded or shortly acute; inflorescence 2-10-flowered, very lax; calyx distinctly gibbous at base |