1	Styles usually 3 and capsules 6-valved or -toothed, or styles rarely 2 and capsules 4-valved or -toothed; petal apex entire or slightly emarginate; sepals never truncate and saccate at base, not excurved.		(2)
+	Styles usually 2, sometimes 3(or 4 or 5); capsule 4-valved or -toothed, rarely 6-, 8-, or 10-valved or -toothed; petal apex entire to fimbriate; sepals truncate and ± saccate at base, excurved (6. A. subgen. Odontostemma).		(44)
2 (1)	Sepals not incrassate at base, veins not obviously impressed; leaf blade subulate to ovate, margin and apex incrassate, apex not setiform but spinose.		(3)
+	Sepals usually (rarely not) incrassate at base, veins usually obvious (rarely not); leaf blade variously shaped, margin and apex not incrassate, or margin scarious, apex spinose when blade aristate.		(13)
3 (2)	Sepal apex obtuse, margin scarious; basal leaf blade subulate to linear-lanceolate, cauline leaf blade imbricate in 4 rows (decussate), ovate, less than 5 mm, persistent; flowers solitary or 3 in cymes; plants congested caespitose or pulvinate (4. A. subgen. Dolophragma).		(4)
+	Sepal apex acute, acuminate, or obtuse, apex and margin usually hard; leaf blade remote or sometimes approximate (covering each other), but never imbricate in 4 rows, lanceolate, elliptic, ovate, or orbicular, more than 5 mm, deciduous, rarely persistent; flower solitary; plants densely caespitose but never pulvinate (5. A. subgen. Solitaria).		(8)
4 (3)	Plants densely caespitose; stems 10--20 cm, glandular villous		33 A. przewalskii
+	Plants densely pulvinate; stems 2.5--15 cm, glandular villous or glabrous.		(5)
5 (4)	Stems 4--15 cm, villous or glandular hairy.		(6)
+	Stems 2.5--6 cm, glabrous.		(7)
6 (5)	Stems 10--15 cm, villous; sepals ovate to lanceolate-ovate		34 A. smithiana
+	Stems 4--9 cm, glandular villous; sepals elliptic		35 A. oreophila
7 (5)	Pedicels 2--4 cm; petals ca. 2 × as long as sepals; anthers violet		36 A. densissima
+	Pedicels absent (flowers sessile); petals slightly longer than sepals; anthers yellow		37 A. polytrichoides
8 (3)	Floral disc large, with 5 obvious glands.		(9)
+	Floral disc small or not impressed, glands small or degenerate.		(10)
9 (8)	Stems 1--15 cm, villous on one side; leaf blade glabrous except ciliate at base; petals white or pink		42 A. forrestii
+	Stems 2--6 cm, villous all round; leaf blade glandular pubescent; petals violet		43 A. glanduligera
10 (8)	Petals violet; anthers violet		41 A. rhodantha
+	Petals white or pink; anthers pale yellow, green, or black.		(11)
11 (10)	Plants hairy throughout; stems diffuse; leaf blade ovate or ovate-orbicular, margin long hairy; petals white; anthers dark green or black		38 A. ciliolata
+	Plants not hairy throughout; stems erect; leaf blade lanceolate or narrowly orbicular, margin shortly hairy or glabrous; petals white or pink; anthers yellow or green.		(12)
12 (11)	Stems 4--6 cm; leaf blade lanceolate or ovate-lanceolate, margin shortly hairy; inflorescence rachis bracteate proximally; sepal apex excurved; petals white or pink; anthers pale yellow		39 A. ramellata
+	Stems 2--5 cm; leaf blade narrowly orbicular, margin glabrous; inflorescence rachis ebracteate proximally; sepal apex erect; petals white; anthers green		40 A. stracheyi
13 (2)	Leaf blade linear to orbicular, or aristate and narrowly linear, margin not obviously scarious; sepal veins inconspicuous; plants solitary or caespitose, rarely compacted pulvinate; leaves deciduous, rarely persistent.		(14)
+	Leaf blade subulate to linear, never setiform or graminoid, margin obviously scarious; sepal veins impressed; plants caespitose to compacted pulvinate; leaves persistent (3. A. subgen. Eremogoneastrum).		(28)
14 (13)	Sepals slightly or not incrassate at base; leaf blade usually linear to ovate, rarely needle-shaped (1. A. subgen. Arenaria).		(15)
+	Sepals markedly incrassate or woody at base; leaf blade linear or linear-subulate, graminoid, rarely aristate with a spinose tip (2. A. subgen. Eremogone).		(20)
15 (14)	Seeds with a flat wing; petals slightly shorter than or equaling sepals		6 A. compressa
+	Seeds wingless; petals shorter than bracts, slightly shorter to longer than sepals.		(16)
16 (15)	Seeds tuberculate with raised papillae; petals usually slightly shorter than sepals		1 A. serpyllifolia
+	Seeds not tuberculate with raised papillae; petals equaling or longer than sepals.		(17)
17 (16)	Seeds with curls; inflorescence usually axillary; leaf blade elliptic to ovate or orbicular.		(18)
+	Seeds reticulate; inflorescence of terminal cymes; leaf blade linear to ovate-saccate.		(19)
18 (17)	Leaf blade elliptic, ovate, or suborbicular; sepals glabrous abaxially		2 A. orbiculata
+	Leaf blade elliptic-lanceolate or obovate; sepals sparsely white villous on veins abaxially		3 A. neelgherrensis
19 (17)	Capsule 1-seeded; leaf blade linear; sepals with papillose spots abaxially		4 A. monosperma
+	Capsule several seeded; leaf blade elliptic to elliptic-ovate; sepals white glandular villous abaxially		5 A. puranensis
20 (14)	Plants completely woody at base; sepals not herbaceous, veins inconspicuous, apex usually acuminate.		(21)
+	Plants not completely woody at base; sepals herbaceous throughout or only at middle, veins impressed, apex usually obtuse, rarely acute or acuminate.		(22)
21 (20)	Leaf blade apex acute; pedicels glabrous, rarely sparsely glandular hairy		14 A. griffithii
+	Leaf blade apex spinose; pedicels densely glandular hairy		15 A. androsacea
22 (20)	Sepals herbaceous only at middle, apex long acuminate, with (1--)3 or more parallel veins		7 A. potaninii
+	Sepals herbaceous ± throughout, apex obtuse, 1-veined.		(23)
23 (22)	Stems with congested, pale brown, long, hardened, dead leaves at base; leaves forming a sheath at base		8 A. juncea
+	Stems without basal leaves as above; leaves not forming a sheath at base.		(24)
24 (23)	Plants pulvinate; stems 4--10 cm; leaf blade linear to subulate, 1.5--5 cm.		(25)
+	Plants congested caespitose; stems 4--20 cm; leaf blade linear, 2--6 cm.		(26)
25 (24)	Stems 4--10 cm, white glandular hairy distally; sepals ± glandular villous		12 A. formosa
+	Stems 6--10 cm, villous distally; sepals glabrous		13 A. haitzeshanensis
26 (24)	Stems 4--10 cm, glandular pubescent distally		11 A. grueningiana
+	Stems 10--20 cm; all or only peduncle proximally glandular hairy, or glabrous.		(27)
27 (26)	Stems glabrous proximally, becoming glandular hairy or villous distally; sepals glabrous		9 A. capillaris
+	Stems hirsutulous throughout; sepals densely glandular hairy		10 A. acicularis
28 (13)	Flowers few, in cymes.		(29)
+	Flowers solitary, rarely paired.		(30)
29 (28)	Stems sparsely villous, 2--3 cm; leaf blade 5--6 mm; sepals 3-veined		31 A. taibaishanensis
+	Stems glandular villous, to 8 cm; leaf blade 0.7--20 mm; sepals usually 1-veined		32 A. festucoides
30 (28)	Flowers sessile.		(31)
+	Flowers pedicellate.		(34)
31 (30)	Sepals violet abaxially; petals pink, lanceolate or orbicular		27 A. shannanensis
+	Sepals green; petals white, ovate, obovate, or saccate.		(32)
32 (31)	Flowers ca. 1.8 cm in diam.; sepals ovate-lanceolate; petals broadly obovate, ca. 1.5 × as long as sepals		28 A. edgeworthiana
+	Flowers ca. 0.8 cm in diam.; sepals elliptic-lanceolate or lanceolate; petals narrowly obovate or saccate, shorter or slightly longer than sepals.		(33)
33 (32)	Sepals elliptic-lanceolate; petals narrowly obovate, slightly longer than sepals; anthers equal; styles equaling ovary		29 A. bryophylla
+	Sepals lanceolate; petals saccate, shorter than sepals; anthers 5 long and 5 short; styles ca. 2.5 × as long as ovary		30 A. zadoiensis
34 (30)	Pedicels glandular villous or villous.		(35)
+	Pedicels glabrous.		(39)
35 (34)	Pedicels villous.		(36)
+	Pedicels glandular villous.		(37)
36 (35)	Sepals lanceolate, glabrous		19 A. kansuensis
+	Sepals narrowly lanceolate, sparsely pilose, at least at base		20 A. ischnophylla
37 (35)	Sepals ovate-lanceolate, 3-veined; petals ovate, ca. 1/3--1/2 as long as sepals		16 A. brevipetala
+	Sepals lanceolate or ovate-lanceolate, 1-veined; petals elliptic, slightly longer than sepals.		(38)
38 (37)	Flowers solitary, rarely paired, pedicel 2.5--5 × as long as bracts; anthers yellow		17 A. baxoiensis
+	Flowers solitary, never paired, pedicel shorter than bracts; anthers black		18 A. kumaonensis
39 (34)	Pedicels 4--10 mm.		(40)
+	Pedicels 1--2 mm.		(41)
40 (39)	Pedicels 5--10 mm; sepals lanceolate, ca. 5 mm; anthers yellow; petals not callose at base		21 A. roborowskii
+	Pedicels ca. 4 mm; sepals elliptic, 3 mm; anthers white; petals with a yellow, oblong callus at base		22 A. lancangensis
41 (39)	Sepals hard, 1-veined, base ciliate, apex greenish brown		23 A. gerzensis
+	Sepals soft, 1--3-veined, base not ciliate, apex green.		(42)
42 (41)	Flowers 6--7 mm in diam.		26 A. pulvinata
+	Flowers ca. 15 mm in diam.		(43)
43 (42)	Sepals linear-lanceolate, 7--8 mm, 1--3 veined; petals elliptic-ovate, 8--9 mm; anthers yellow		24 A. qinghaiensis
+	Sepals lanceolate, 6--7 mm, closely 3-veined; petals obovate, 4--5 mm; anthers violet		25 A. aksayqingensis
44 (1)	Petal apex toothed or fimbriate; filaments opposite sepals with a gland at base; styles 2.		(45)
+	Petal apex entire, slightly emarginate, or shallowly 2-cleft, rarely lobes with 3 shallow, round teeth; filaments opposite sepals with a gland at base or not; styles 2 or 3(--5).		(67)
45 (44)	Petals fimbriate or toothed.		(46)
+	Petal apex toothed.		(56)
46 (45)	Roots conic.		(47)
+	Roots fusiform, solitary or caespitose, rarely each node of rhizome globose or clavate, forming a moniliform chain.		(48)
47 (46)	Leaf blade 0.5--1.5 × 0.2--1 cm; sepals 4--10 mm; petals slightly longer than sepals		101 A. delavayi
+	Leaf blade 1--3 × 0.5--0.6 cm; sepals 3--6 mm; petals ca. 2 × as long as sepals		102 A. yunnanensis
48 (46)	Roots moniliform		100 A. monilifera
+	Roots fusiform.		(49)
49 (48)	Leaves glabrous; sepal margin black ciliate		92 A. salweenensis
+	Leaves often glandular pubescent; sepals glandular pubescent but margin not black ciliate.		(50)
50 (49)	Anthers yellow, rarely green.		(51)
+	Anthers black, violet, or yellowish brown (rarely yellow in A. iochanensis).		(53)
51 (50)	Stems 10--25 cm; leaf blade narrowly elliptic, orbicular-elliptic, or orbicular-lanceolate; pedicels villous or glandular hairy		97 A. fimbriata
+	Stems 40--60 cm; leaf blade narrowly elliptic-saccate, ovate-elliptic, or ovate; pedicels multicellular pubescent or glandular hairy.		(52)
52 (51)	Plants annual or biennial; stems 30--60 cm; leaves to 40 cm; seeds 2 or 3		98 A. debilis
+	Plants perennial; stems 10--40 cm; leaves to 15 cm; seeds 11 or 12		99 A. polysperma
53 (50)	Plants hispid; leaf blade ovate or orbicular-elliptic		93 A. trichophora
+	Plants glandular or shortly villous; leaf blade broadly lanceolate, orbicular-ovate, or orbicular.		(54)
54 (53)	Stem solitary, branched below middle; leaf blade orbicular-obovate or orbicular, 3--10 mm wide; seeds 2--4, wingless; roots several clustered together		96 A. barbata
+	Stems branched at base, procumbent, diffuse, or erect; leaf blade lanceolate, 1--4 mm wide; seeds numerous, with a narrow wing; root solitary.		(55)
55 (54)	Stems procumbent or erect; leaf blade usually broadly lanceolate, 2--4 mm wide; pedicels 0.5--1.5 cm; petal apex fimbriate; anthers violet or black		94 A. yulongshanensis
+	Stems diffuse; leaf blade narrowly lanceolate, 1--3 mm wide; pedicels 0.5--2 cm; petal apex slightly toothed; anthers yellow		95 A. iochanensis
56 (45)	Roots solitary or several clustered together, spinose, rarely conic.		(57)
+	Roots conic, fleshy, rarely fibrous.		(62)
57 (56)	Stems slender; leaves glabrous or sparsely hairy; petal apex 4-toothed.		(58)
+	Stems rigid; leaves variously hairy; petal apex with small teeth.		(59)
58 (57)	Stems glandular pubescent with 2 lines of hairs; leaves sparsely hairy; petals obovate or narrowly elliptic		80 A. quadridentata
+	Stems and leaves glabrous; petals obovate or cuneate		81 A. giraldii
59 (57)	Leaf blade ovate or ovate-orbicular; sepals orbicular-ovate or orbicular-lanceolate		85 A. fridericae
+	Leaf blade mostly ovate-lanceolate or ovate; sepals lanceolate, rarely ovate.		(60)
60 (59)	Sepals long villous; petals longer than sepals, but less than 2 × as long as them		82 A. trichophylla
+	Sepals villous or glandular hairy; petals more than 1.5 × as long as sepals.		(61)
61 (60)	Stems to 1.5 cm, with numerous branches; flower solitary, terminal, to 1.5 cm in diam.; anthers violet to yellow-brown		83 A. pogonantha
+	Stems to 30 cm, distally with branched, dichasial cymes; flowers small, to 0.8 cm in diam.; anthers blue-green to yellow		84 A. dimorphitricha
62 (56)	Roots fibrous; stems brown glandular villous; leaf blade tuberculate on both surfaces, petiole 2--5 mm		86 A. longicaulis
+	Roots conic, fleshy; stems glabrous, subglabrous, or glandular hairy; leaf blade not tuberculate, petiole 1--2 cm or leaves sessile.		(63)
63 (62)	Stems glabrous or subglabrous; petiole 1--2 cm (at least proximal cauline leaves petiolate)		87 A. longipetiolata
+	Stems villous or glandular hairy; leaves sessile or shortly petiolate.		(64)
64 (63)	Stems pale brown, villous.		(65)
+	Stems green, glandular hairy.		(66)
65 (64)	Stems 4--7 cm; leaf blade elliptic or obovate-elliptic; sepals long villous abaxially		88 A. leucasteria
+	Stems 10--15 cm; leaf blade elliptic to broadly elliptic-saccate; sepals sparsely glandular pubescent abaxially		89 A. nivalomontana
66 (64)	Leaf blade thin, glabrous or glandular hairy; sepals narrowly ovate, glabrous; petals ca. 1.5 × as long as sepals; cymes spreading		90 A. omeiensis
+	Leaf blade thick, villous with yellowish, small, nodose hairs; sepals orbicular-lanceolate, long pubescent abaxially; petals slightly longer than sepals; cymes compact		91 A. auricoma
67 (44)	Filaments opposite sepals with a gland at base; seeds globose or reniform, smooth or tuberculate.		(68)
+	Filaments opposite sepals without a gland at base or gland not obvious; seeds oblate or reniform, glabrous or with small, raised tubercles, or flat but margin with a narrow wing.		(72)
68 (67)	Stems villous with 2 lines of hairs; sepals glabrous or only ciliate at margin.		(69)
+	Stems glandular villous, or with long, nodose bristles; sepals glandular villous or glandular villous mixed with long, nodose bristles.		(70)
69 (68)	Styles 6--7 mm; petal apex entire; leaves aggregated at stem apex, leaf blade broadly linear or linear-lanceolate		75 A. longistyla
+	Styles ca. 1.5 mm; petal apex 2-cleft; leaves in several distant pairs, leaf blade saccate		76 A. ionandra
70 (68)	Stems and sepals densely hairy mixed with long, nodose bristles; petals ca. 10 mm		77 A. longiseta
+	Stems and sepals hairy, without nodose bristles; petals 5--8 mm.		(71)
71 (70)	Leaf blade obsaccate, petiole short; sepals 2--3 mm		78 A. chamdoensis
+	Leaf blade linear-lanceolate, petiole absent; sepals 5--6 mm		79 A. szechuensis
72 (67)	Seeds usually flat, with a narrow wing.		(73)
+	Seeds reniform, subglobose, globose, or oblate, smooth or tuberculate, wingless.		(82)
73 (72)	Stems diffuse; flowers usually several in cymes.		(74)
+	Stems erect or suberect; flowers solitary, rarely paired.		(76)
74 (73)	Stems sparsely villous; petals oblanceolate or obovate, apex 2- or 3-toothed		67 A. euodonta
+	Stems glandular hairy; petals obovate or broadly ovate, apex entire or emarginate.		(75)
75 (74)	Leaf blade orbicular-lanceolate or orbicular; petals broadly ovate, apex emarginate		65 A. melanandra
+	Leaf blade linear-lanceolate; petals ovate, apex entire		66 A. pseudostellaria
76 (73)	Stems 3--6 cm, glabrous proximally		68 A. dsharaensis
+	Stems 4--25 cm, villous or glandular hairy.		(77)
77 (76)	Plants to 6 cm tall, white villous in 2 lines or white, yellow, or black nodose villous; petals white.		(78)
+	Plants 4--25 cm tall, glandular villous; petals white, pink, or violet.		(79)
78 (77)	Plants 5--6 cm tall; stems white villous in 2 lines; petal apex entire		74 A. monantha
+	Plants to 4 cm tall; stems white, yellow, or black nodose villous; petal apex emarginate, often with a few small teeth		73 A. inornata
79 (77)	Petal apex entire or emarginate; cauline leaf blade lanceolate, elliptic, ovate, or orbicular.		(80)
+	Petal apex entire or shallowly 2-cleft; cauline leaf blade linear-lanceolate or lanceolate, sometimes elliptic.		(81)
80 (79)	Stems white; leaf blade violet; petal apex entire		69 A. melandryoides
+	Stems violet; leaf blade green; petal apex slightly emarginate		70 A. rockii
81 (79)	Petals pink, apex shallowly 2-cleft		71 A. roseiflora
+	Petals white, apex entire		72 A. melandryiformis
82 (72)	Plants usually 8--20 cm tall; proximal flowers of stem with petals and anthers reduced, distal flowers of stem with petals and anthers not reduced.		(83)
+	Plants rarely more than 8 cm tall, or very slender when more than 8 cm tall; petals and stamens sometimes degenerate or reduced to various degrees, petals (when present) ca. 2/3 as long as or equaling sepals.		(90)
83 (82)	Styles 3(or 5).		(84)
+	Styles 2.		(87)
84 (83)	Principal root napiform or conic, unbranched.		(85)
+	Principal root conic, fleshy, many branched.		(86)
85 (84)	Petals white; stems white; leaves glabrous		47 A. filipes
+	Petals white or pink; stems white or violet; leaves ciliate at base, otherwise glabrous		46 A. napuligera
86 (84)	Petal apex shallowly 2-lobed, lobes with small, irregular teeth; stems and leaves with septate hairs		45 A. setifera
+	Petal apex rounded, emarginate, or bifid to near middle of petal; stems and leaves with non-septate hairs		44 A. weissiana
87 (83)	Leaf blade linear-lanceolate, to 1.5 cm, glabrous, margin not cartilaginous; stamens 5		51 A. schneideriana
+	Leaf blade lanceolate to orbicular, to 4 cm, subglabrous, margin cartilaginous; stamens 10.		(88)
88 (87)	Leaf blade narrowly elliptic to suborbicular, 8--15 mm wide		48 A. nigricans
+	Leaf blade lanceolate to oblanceolate, 1--5 mm wide.		(89)
89 (88)	Leaf blade lanceolate or oblanceolate, 1--2 cm × 2--5 mm; sepals lanceolate, pubescent or with white, septate, glandular hairs, margin hairy; petal apex 2-cleft		49 A. zhongdianensis
+	Leaf blade oblanceolate, 0.5--2.5 cm × 1--5 mm; sepals ovate or ovate-lanceolate, densely shortly hairy at base; petal apex entire		50 A. xerophila
90 (82)	Petals absent or only 2 or 3 developed, reduced to various degrees.		(91)
+	All floral parts present.		(94)
91 (90)	Sepals 5; petals absent.		(92)
+	Sepals 4; petals present or absent.		(93)
92 (91)	Stamens 5; leaf blade rhomboid-elliptic to saccate; stem with 1 or 2 lines of hairs		61 A. reducta
+	Stamens 2 or 3; leaf blade linear to linear-lanceolate; stem with 2 lines of hairs		62 A. pharensis
93 (91)	Petals absent; stamens 2 or 3; sepals and leaves fleshy; pedicels and sepals glabrous		63 A. littledalei
+	Petals present; stamens 8; sepals and leaves not fleshy; pedicels and sepals hairy		64 A. saginoides
94 (90)	Styles 3.		(95)
+	Styles 2(or 3).		(96)
95 (94)	Leaf blade subulate, 4--5 × ca. 1 mm		52 A. minima
+	Leaf blade saccate, 5--12 × 2--3 mm		53 A. bomiensis
96 (94)	Petals shorter than sepals.		(97)
+	Petals equaling or longer than sepals.		(98)
97 (96)	Cauline leaf blade ovate, petiole 0.5--1.5 cm; sepals white villous abaxially, margin membranous; petals ca. 2/3 as long as sepals, apex entire; styles 2		54 A. longipes
+	Cauline leaf blade lanceolate, petiole absent or inconspicuous; sepals hairy abaxially and at margin; petals shorter than sepals, apex entire, sometimes 2-cleft; styles 2 or 3		55 A. inconspicua
98 (96)	Petals 1.5--2 × as long as sepals; sepals leathery		56 A. amdoensis
+	Petals equaling or up to 1.5 × as long as sepals; sepals herbaceous.		(99)
99 (98)	Roots conic, fleshy; leaf blade linear or saccate.		(100)
+	Roots slender, fibrous, or with a rhizome; leaf blade linear-lanceolate or elliptic.		(101)
100 (99)	Leaf blade linear; sepals glabrous, with wide membranous margin; petal apex entire		58 A. membranisepala
+	Leaf blade saccate; sepals densely glandular pubescent abaxially; petal apex slightly emarginate or shallowly lobed		57 A. spathulifolia
101 (99)	Leaf blade linear-lanceolate, herbaceous, margin ciliate; petal apex erose		59 A. karakorensis
+	Leaf blade elliptic, leathery, margin glabrous; petal apex entire		60 A. tumengelaensis