1	Annual herbs		(2)
+	Perennial herbs or shrublets		(8)
2 (1)	Legumes narrowly linear, curved, terete, 1-locular, slightly constricted between seeds; stipules minute, free; racemes sessile to subsessile, few flowered.		5 A. sect. Ophiocarpus (p. 335)
+	Legumes never linear and curved, never constricted; other characters different		(3)
3 (2)	Calyx teeth very unequal in length; keel always longer than wings		(4)
+	Calyx teeth ± equal in length; keel shorter than wings		(5)
4 (3)	Petals whitish or yellowish; legumes falcate to screwlike twisted.		3 A. sect. Cycloglottis (p. 334)
+	Petals violet; legumes curved.		4 A. sect. Heterodontus (p. 335)
5 (3)	Standard in middle distinctly transversely dilated; legumes with a hooked or bent beak, with an indumentum of short appressed and longer spreading hairs.		1 A. sect. Ankylotus (p. 333)
+	Standard never dilated in middle; other characters different		(6)
6 (5)	Standard without distinct claw; legumes with sharp edges or wings on sides.		6 A. sect. Oxyglottis (p. 336)
+	Standard with a distinct claw; legumes without sharp edges or wings		(7)
7 (6)	Racemes elongated.		2 A. sect. Haematodes (p. 334)
+	Racemes densely capitate.		7 A. sect. Onycholobium (p. 336)
8 (1)	Plants with medifixed or asymmetrically bifurcate hairs		(9)
+	Hairs of plants simple, basifixed, or plants completely glabrous		(37)
9 (8)	Strongly branched, subspherical spiny shrublets.		55 A. sect. Bulimioides (p. 443)
+	Plants never spiny		(10)
10 (9)	All stipules or rarely only those of lower leaves distinctly vaginate-connate behind stem		(11)
+	All stipules free from each other		(23)
11 (10)	Plants acaulescent or nearly so		(12)
+	Plants with a well-developed stem		(14)
12 (11)	Calyx soon after beginning of anthesis enlarging and becoming bladderlike inflated; legumes included in persistent calyx.		59 A. sect. Laguropsis (p. 448)
+	Calyx tubular up to fruiting time, ruptured by legume		(13)
13 (12)	Legumes bladderlike inflated, membranous.		48 A. sect. Cystium (p. 428)
+	Legumes not bladderlike inflated, leathery.		45 A. sect. Helmia (p. 421)
14 (11)	Calyx soon after beginning of anthesis enlarging and becoming bladderlike inflated; legumes included in persistent calyx		(15)
+	Calyx tubular up to fruiting time, ruptured by legume		(16)
15 (14)	Plants shrubby to subshrubby.		57 A. sect. Cysticalyx (p. 444)
+	Plants herbaceous.		58 A. sect. Hypsophili (p. 447)
16 (14)	Flowers in loose, rather elongated racemes		(17)
+	Flowers in capitate or subumbelliform racemes, rarely elongated		(20)
17 (16)	Petals yellowish green.		36 A. sect. Uliginosi (p. 405)
+	Petals lilac or violet		(18)
18 (17)	Calyx mostly long tubular; legumes linear.		40 A. sect. Ornithopodium (p. 409)
+	Calyx campanulate or shortly campanulate-tubular; legumes ovoid to oblong		(19)
19 (18)	Shrubby or subshrubby psammophytes; leaflets in 1-3 pairs or solitary; legumes up to 8 mm, with ± long spreading hairs, if legumes longer and appressed hairy, then leaflets in only 1 pair or solitary.		54 A. sect. Ammodendron (p. 442)
+	Plants herbaceous; leaflets usually in at least 5 pairs, if in only 3 pairs, then legumes 11-16 mm and covered with appressed hairs.		38 A. sect. Craccina (p. 407)
20 (16)	Dwarf pulvinate plants with short, prostrate stems; flowers 1 or 2 in leaf axils, subsessile; stipules completely connate into a tubular sheath surrounding stem and base of petiole.		43 A. sect. Ammodytes (p. 419)
+	Plants with erect stems		(21)
21 (20)	Calyx tubular, at least 9-10 mm, slightly inflated after anthesis.		46 A. sect. Ammotrophus (p. 425)
+	Calyx campanulate, 5-8 mm, never inflated		(22)
22 (21)	Bracteoles present.		37 A. sect. Brachycephali (p. 406)
+	Bracteoles absent.		39 A. sect. Onobrychides (p. 409)
23 (10)	Plants always with a well-developed stem (sometimes some stems of a plant short)		(24)
+	Plants acaulescent or nearly so, rarely with a short stem		(30)
24 (23)	All petals appressed hairy.		50 A. sect. Tanythrix (p. 429)
+	All petals glabrous		(25)
25 (24)	Legumes bladderlike inflated, valves membranous.		47 A. sect. Leucophysa (p. 426)
+	Legumes not bladderlike inflated, valves leathery		(26)
26 (25)	Calyx soon after beginning of anthesis enlarging and becoming bladderlike inflated.		56 A. sect. Chaetodon (p. 443)
+	Calyx tubular, unchanged until fruiting time, ruptured by peduncle		(27)
27 (26)	Ovary and legumes covered with appressed to subappressed hairs, rarely also with some ascending hairs.		41 A. sect. Xiphidium (p. 413)
+	Ovary and legumes villous with ascending to spreading hairs		(28)
28 (27)	Racemes subsessile.		50 A. sect. Tanythrix (p. 429)
+	Peduncles slightly shorter to longer than leaves		(29)
29 (28)	Legumes shortly acuminate or with a beak up to 2 mm.		44 A. sect. Erioceras (p. 419)
+	Legumes with a beak ca. 10 mm.		53 A. sect. Cytisodes (p. 441)
30 (23)	Calyx soon after beginning of anthesis enlarging and becoming bladderlike inflated; legumes included in persistent calyx		(31)
+	Calyx tubular, unchanged until fruiting time, ruptured by legume		(32)
31 (30)	Leaves with ascending to spreading hairs.		56 A. sect. Chaetodon (p. 443)
+	Leaves with appressed hairs.		59 A. sect. Laguropsis (p. 448)
32 (30)	Raceme ovoid to cylindric, with a long peduncle		(33)
+	Raceme loosely subumbelliform or flowers subradical		(34)
33 (32)	Leaflets linear to very narrowly elliptic, to 3(-4) mm wide; peduncle 5-14 cm.		42 A. sect. Corethrum (p. 417)
+	Leaflets elliptic, 4-15 mm wide; peduncle up to 30 cm.		52 A. sect. Podochreati (p. 440)
34 (32)	Legumes bladderlike inflated.		49 A. sect. Paracystium (p. 428)
+	Legumes not bladderlike inflated		(35)
35 (34)	Legumes with a prominent, rigid, long beak 5-8 mm.		53 A. sect. Cytisodes (p. 441)
+	Legumes shortly acuminate or with a very short beak		(36)
36 (35)	Racemes with peduncle 3-8 cm; legumes linear, 3-4 cm.		44 A. sect. Erioceras (A. yangchangii; p. 419)
+	Racemes subsessile or more rarely with a peduncle up to 2 cm; legumes shorter.		51 A. sect. Trachycercis (p. 429)
37 (8)	Plants spiny, shrubby, mostly cushionlike; leaves paripinnate.		34 A. sect. Aegacantha (p. 404)
+	Plants herbaceous or subshrubby; leaves imparipinnate, rarely becoming spiny with age		(38)
38 (37)	Style with a distinctly hairy stigma		(39)
+	Style glabrous at and below stigma, rarely below stigma with a row of short hairlets, very rarely stigma very minutely hairy		(41)
39 (38)	Bracteoles absent; stipules often vaginate-connate, at least lower ones.		12 A. sect. Skythropos (p. 353)
+	Bracteoles always present, at least at beginning of anthesis; stipules always free from each other		(40)
40 (39)	Bracts caducous and mostly missing at fruiting time; plants often tall with thick stems; legumes inflated.		10 A. sect. Coluteocarpus (p. 347)
+	Bracts persistent, always present at fruiting time; plants often smaller with slender stems; legumes distinctly to strongly compressed laterally.		9 A. sect. Pseudosesbanella (p. 346)
41 (38)	Standard hairy		(42)
+	All petals glabrous		(44)
42 (41)	Inflorescence cylindric, 7-9 cm, densely many flowered.		30 A. sect. Alopecias (p. 396)
+	Inflorescence not as above, mostly loosely few flowered		(43)
43 (42)	Leaflets adaxially with long, flexuous, cottonlike hairs.		33 A. sect. Erionotus (p. 403)
+	Leaflets adaxially glabrous or appressed hairy.		31 A. sect. Myobroma (p. 397)
44 (41)	Leaflets verticillate in several mostly remote whorls.		32 A. sect. Gontscharoviella (p. 402)
+	Leaflets all opposite or subopposite		(45)
45 (44)	Upper edge of keel limbs for whole length or in upper part furnished with minute teeth.		31b A. "Purpurascentes group" (p. 401)
+	Margins of keel limbs entire, never furnished with minute teeth		(46)
46 (45)	Calyx at anthesis tubular to slightly ventricose, soon bladderlike inflated and distinctly netlike nerved; legumes stalked, included in calyx.		35 A. sect. Eremophysa (p. 405)
+	Calyx never inflated after anthesis, ruptured by ripe legume		(47)
47 (46)	Inflorescences large, subsessile to shortly pedunculate, ovoid to cylindric, densely many flowered.		30 A. sect. Alopecias (p. 396)
+	Inflorescence not as above		(48)
48 (47)	Hairs mostly with a very short, subacute, basal appendix and therefore extremely asymmetrically bifurcate; leaflets 2-4 × 2-3 mm, both surfaces rather densely spotted with minute blackish dots.		27 A. sect. Irinaea (p. 391)
+	Hairs basifixed; leaflets without blackish dots		(49)
49 (48)	Plants acaulescent or subacaulescent; stems, if present, at most up to 4 cm		(50)
+	Plants distinctly caulescent		(58)
50 (49)	Stipules embracing stem but not connate behind it, high connate around petiole; legumes 25-50 mm, strongly compressed laterally, glabrous.		15 A. sect. Hookeriani (p. 356)
+	Stipules and legumes not as above		(51)
51 (50)	Petals pale yellowish; stipules 1-2 mm.		23 A. sect. Poliothrix (A. yangii; p. 381)
+	Petals purple to violet, yellow, or white; stipules distinctly longer		(52)
52 (51)	Stipules vaginate-connate behind stem or before petiole; petals purple to violet; ovary and legumes sessile or subsessile		(53)
+	Stipules never vaginate-connate; petals yellow or white, or if violet then ovary and legumes long stipitate		(55)
53 (52)	Stipules free from petiole; racemes 1- or 2-flowered.		17 A. sect. Komaroviella (A. damxungensis; p. 357)
+	Stipules adnate to petiole; racemes with more flowers		(54)
54 (53)	Plants at most up to 10 cm tall; calyx 3-6 mm.		26 A. sect. Pseudotapinodes (p. 390)
+	Plants more than 10 cm tall; calyx 7-9 mm.		12 A. sect. Skythropos (p. 353)
55 (52)	Ovary and legumes with a stipe at least 4 mm		(56)
+	Ovary and legumes sessile or subsessile		(57)
56 (55)	Stipules distinctly adnate to petiole.		31a A. "Caprini group" (p. 397)
+	Stipules free from petiole.		12 A. sect. Skythropos (p. 353)
57 (55)	Plants with spreading hairs; petals white.		14 A. sect. Lithophili (p. 355)
+	Plants with appressed hairs; petals bright yellow.		28 A. sect. Lotidium (p. 392)
58 (49)	Stems stout, 3-10 mm or more in diam., ± erect; plants mostly tall with long erect stems		(59)
+	Stems ± slender, at most up to 3 mm in diam., often prostrate to ascending		(65)
59 (58)	Stipules vaginate-connate behind stem		(60)
+	Stipules free from each other		(61)
60 (59)	Standard 34-39 mm; legumes ± globose, 15-22 mm in diam., with very thick walls and a narrow, hollow, very densely long hairy.		29 A. sect. Lithoon (p. 395)
+	Standard up to 17 mm; legumes not as above.		11 A. sect. Chlorostachys (p. 347)
61 (59)	Keel distinctly longer than wings; legumes nut-shaped, 9-14 mm, glabrous.		13 A. sect. Nuculiella (p. 355)
+	Keel shorter or at most as long as wings; legumes not nut-shaped		(62)
62 (61)	Racemes subsessile or with a short peduncle; plants densely spreading hairy all over.		14 A. sect. Lithophili (p. 355)
+	Racemes with a distinct, long peduncle; plants in most parts appressed hairy or subglabrous		(63)
63 (62)	Plants completely glabrous; stipules distinctly longitudinally nerved; ovary and legumes subsessile.		31 A. sect. Myobroma (A. luculentus; p. 397)
+	Plants in most parts appressed hairy or subglabrous; stipules not distinctly nerved; legumes mostly with a distinct to long stipe; bracteoles sometimes present		(64)
64 (63)	Legumes 1-locular; bracts persistent.		8 A. sect. Cenantrum (p. 338)
+	Legumes incompletely to completely 2-locular; bracts persistent or soon falling.		11 A. sect. Chlorostachys (p. 347)
65 (58)	Leaves 6-10 cm, at end of vegetation period elongating up to 25 cm; petiole 1-3 cm, later up to 6 cm, like rachis slender, later thickened and hardened, persistent, glabrous or very sparsely subappressed hairy; leaflets in 13-15 pairs, often caducous.		16 A. sect. Pelta (p. 357)
+	Leaves with other characters		(66)
66 (65)	Stipules free from each other and mostly free from petiole		(67)
+	Stipules all or at least of lower leaves distinctly vaginate-connate behind stem		(75)
67 (66)	Plants with long, prostrate to erect or creeping stems; racemes subumbellate, few flowered; legumes linear, erect.		28 A. sect. Lotidium (p. 392)
+	Plants with ascending to erect stems; racemes not subumbellate; legumes of other form		(68)
68 (67)	Wing limbs with linear-acute auricle 2-4.5 mm, sometimes as long as claw		(69)
+	Auricles of wing limbs mostly shorter, never linear and acute		(70)
69 (68)	Plants up to 60 cm tall; stipules mostly 3-5 mm; inflorescences several on 1 stem; standard ovate or obovate, abruptly contracted at base into very short claw; legumes 8-12 mm.		24 A. sect. Chrysopteri (p. 389)
+	Plants 8-18 cm tall; stipules 6-15 mm; inflorescence solitary on 1 stem; standard widely obovate to nearly orbicular, gradually narrowed at base; legumes 15-28 mm.		25 A. sect. Ebracteolati (p. 389)
70 (68)	Leaves with a distinct petiole 2-4.5 cm.		12 A. sect. Skythropos (p. 353)
+	Leaves subsessile, with a petiole up to 1(-2) cm		(71)
71 (70)	Plants mostly tall, conspicuously leafy; ovary and legumes with a distinct, slender stipe, often distinctly longer than 10 mm		(72)
+	Plants often low, not conspicuously leafy; ovary and legumes sessile or very shortly stipitate		(73)
72 (71)	Legumes 1-locular; bracts persistent; bracteoles absent.		8 A. sect. Cenantrum (p. 338)
+	Legumes 2-locular or incompletely so; bracts persistent or soon falling; bracteoles present or absent.		11 A. sect. Chlorostachys (p. 347)
73 (71)	Racemes long, remotely many flowered; legumes globose to subglobose.		20 A. sect. Melilotopsis (p. 370)
+	Racemes at anthesis short, dense, sometimes elongated in fruit; legumes globose to narrowly ovoid		(74)
74 (73)	Legumes globose to widely ovoid, at most up to 2 × as long as wide, often cross-wrinkled.		21 A. sect. Brachycarpus (p. 373)
+	Legumes ovoid to narrowly ovoid, at least 2 × as long as wide but mostly longer, very rarely cross-wrinkled.		19 A. sect. Oroboidei (p. 365)
75 (66)	Keel longer than (rarely as long as) wings, limbs always large, wider than those of wings.		17 A. sect. Komaroviella (p. 357)
+	Keel distinctly shorter than wings, rarely to as long as wings, with narrower limbs		(76)
76 (75)	Wing limbs distinctly emarginate to deeply bilobed		(77)
+	Wing limbs rounded at apex to rarely slightly emarginate		(79)
77 (76)	Ovary and legumes with a long, slender stipe.		22 A. sect. Hemiphragmium (p. 380)
+	Ovary and legumes sessile or subsessile		(78)
78 (77)	Legumes globose to widely ovoid, at most up to 2 × as long as wide, often cross-wrinkled, hairy.		21 A. sect. Brachycarpus (p. 373)
+	Legumes ovoid to narrowly ovoid, at least 2 × as long as wide but mostly longer, never distinctly cross-wrinkled, glabrous or rarely very sparsely hairy.		19 A. sect. Oroboidei (p. 365)
79 (76)	Inflorescence subumbellate, few flowered or a loose raceme; legumes linear, erect.		28 A. sect. Lotidium (p. 392)
+	Inflorescence at anthesis a dense, many-flowered raceme, often elongating in fruit; legumes of other form		(80)
80 (79)	Standard at least 14 mm, at base with a sometimes short, but mostly distinct, cuneate claw		(81)
+	Standard 6-10 mm, rarely up to 12 mm, mostly without distinct claw		(82)
81 (80)	Stems, stipules, and rachis with ± spreading hairs; ovary with a stipe 3.5-5 mm.		12 A. sect. Skythropos (p. 353)
+	Stems, stipules, and rachis with appressed to slightly ascending hairs; ovary and legumes sessile or subsessile.		18 A. sect. Glycyrrhizi (p. 363)
82 (80)	Inflorescence ovoid to shortly cylindric; legumes narrowly ellipsoid to narrowly oblong, distinctly curved to sometimes semicircular curved, sessile to stipitate, 1-locular or rarely very incompletely 2-locular.		23 A. sect. Poliothrix (p. 381)
+	Inflorescence capitate to shortly ovoid; legumes globose to ovoid, sessile, 1-locular or 2-locular		(83)
83 (82)	Legumes globose to widely ovoid, at most up to 2 × as long as wide, often cross-wrinkled.		21 A. sect. Brachycarpus (p. 373)
+	Legumes ovoid to narrowly so, at least 2 × as long as wide, mostly longer, never distinctly cross-wrinkled.		19 A. sect. Oroboidei (p. 365)