1	Plants with slender stems up to 90 cm, at least in lower 1/2 with long, horizontally spreading lateral branches; hairs slender, 0.1-0.4 mm.		8 P. eutrichus
+	Stems mostly shorter, without horizontally spreading lateral branches, if sometimes as long as above, then with other kinds of hair		(2)
2 (1)	Plants in all parts covered with bladderlike, scalelike hairs up to 0.1 mm.		4 P. chinense
+	Plants at least at calyx with slender, longer, not bladderlike hairs		(3)
3 (2)	Petals yellow, rarely with violet-tipped keel		(4)
+	Petals blue or violet, rarely yellow at base only		(6)
4 (3)	Plants 30-75 cm tall; calyx 7-12 mm, teeth 4-9 mm; keel as long as wings.		5 P. dolichochaete
+	Plants 10-50 cm tall; calyx up to 10 mm, teeth up to 6 mm; keel longer than wings		(5)
5 (4)	Leaflets in 7-13 pairs, 5-16 × 1-4 mm, distinctly more than 2 × as long as wide; peduncles 3-11 cm.		9 P. flavovirens
+	Leaflets in 4-10 pairs, 5-10 × 2.5-5 mm, ca. 2 × as long as wide; peduncles 1.5-4 cm.		2 P. camptodontum
6 (3)	Plants at least in part with spreading hairs		(7)
+	Plants with appressed to ascending hairs only		(11)
7 (6)	Calyx 8-10 mm, white hairy, teeth 4.5-6 mm; standard 15-19 mm; legumes with a stipe ca. 5 mm, 25-30 mm, 2-locular.		21 P. turgidocarpum
+	Calyx shorter, white and black hairy, teeth mostly shorter; standard 7-13 mm; legumes with a stipe up to 3 mm or subsessile, up to 20 mm, 1-locular		(8)
8 (7)	Leaflets 8-20 mm; bracts 8-10 mm; calyx 7-8 mm, with teeth 4-5 mm.		12 P. lineariauriferum
+	Leaflets distinctly smaller; bracts at most up to 4 mm; calyx up to 6 mm with shorter teeth		(9)
9 (8)	Stipules 2.5-4.5 mm; leaflets 3-15 mm; bracts 1.5-4 mm; bracteoles 0.5-2 mm; calyx teeth 1.5-4 mm; legumes 5-6.5 mm high and wide.		20 P. tribulifolium
+	Stipules up to 2.5 mm; leaflets 2-6 mm; bracts up to 2 mm; bracteoles mostly absent, if present, then ca. 0.3 mm (in P. milingense); calyx teeth up to 2.5 mm; legumes either much higher than wide or much wider than high		(10)
10 (9)	Stems with appressed hairs; leaflets loosely to rather densely hairy adaxially; bracts 1.5-2 mm; legumes 15-20 mm, 8-12 mm high, strongly compressed laterally, without beak.		10 P. heydei
+	Stems with partly spreading hairs; leaflets glabrous to subglabrous adaxially; bracts 0.6-1 mm; legumes 10-15 mm, 2.5-3 mm high and 5-7 mm wide, with a short beak.		13 P. milingense
11 (6)	Leaflets on both surfaces loosely to densely hairy		(12)
+	Leaflets adaxially glabrous or rarely sparsely hairy		(13)
12 (11)	Stipules 2-3 mm; bracts 4-6 mm, with spreading hairs; calyx 7-8 mm, covered with spreading white and dark brown hairs.		3 P. chapmanianum
+	Stipules 4-7 mm; bracts 6-10 mm, with appressed to ascending hairs; calyx 9-10 mm, covered with appressed to ascending white and shorter black hairs.		11 P. lasaense
13 (11)	Standard up to 10 mm; bracts up to 2 mm; bracteoles absent		(14)
+	Standard at least 12 mm; bracts mostly distinctly longer		(16)
14 (13)	Plants up to 50 cm tall; calyx 7-8 mm; legumes 25-30 mm.		17 P. siccaneum
+	Plants up to 30 cm tall; calyx up to 5.5 mm; legumes up to 13 mm		(15)
15 (14)	Stem and peduncles loosely to rather densely hairy; leaflets narrowly elliptic, 3-11 × 1-2 mm, acute; keel as long as wings.		15 P. prodigiosum
+	Stem and peduncles glabrous to sparsely hairy; leaflets elliptic, 4-9 × 1.5-4 mm, obtuse; keel distinctly longer than wings.		16 P. sanbilingense
16 (13)	Stem, rachises, and peduncles glabrous or sparsely hairy; leaflets 10-30 × 3.5-10 mm.		14 P. pastorium
+	Stem, rachises, and peduncles loosely to rather densely hairy, sometimes only sparsely hairy; leaflets up to 12 mm		(17)
17 (16)	Stem, rachises, and peduncles covered with hairs up to 0.15 mm and also with much shorter, minute, nearly globose hairs; calyx teeth 2.5-3 mm; legumes very shortly acuminate.		7 P. enneaphyllum
+	Stems without minute subglobose hairs; at least longer calyx teeth 3.5-6 mm; legumes with a beak 2-4 mm		(18)
18 (17)	Stipules 1-3 mm, lower ones completely embracing stem but free from each other; keel shorter than wings.		6 P. donianum
+	Stipules 3-5 mm, lower ones not or up to 1/2 embracing stem; keel longer than wings		(19)
19 (18)	Plants 20-40(-60) cm tall; racemes 2-7(-9)-flowered; petals violet or in lower part yellow.		1 P. balfourianum
+	Plants 10-25 cm tall; stipules not embracing stem, never reflexed; racemes 1-5-flowered; petals purple or purple-red and standard in middle with a white, purple-striate spot		(20)
20 (19)	Leaflets narrowly obovate, 2-3 mm wide; bracteoles 2-3(-4) mm; standard purple-red, ca. 16 mm, limb ca. 14 mm wide, transversely elliptic, in middle with a white, purple-striate spot.		19 P. tingriense
+	Leaflets widely obovate, 3.3-6 mm wide; bracteoles absent or up to 1 mm; standard purple, ca. 12 mm, limb ca. 8 mm wide, suborbicular.		18 P. sichuanense