1	Fruit with wings or bristles membranous-saccate.		1 C. calliphysa
+	Fruit with wings or bristles not membranous-saccate.		(2)
2 (1)	Fruit with wings along ribs; not with bristles; wings entire.		(3)
+	Fruit with bristles on ribs or narrow wings with bristles at margin.		(5)
3 (2)	Old branches light gray or yellow; wings nearly membranous, softer.		2 C. leucocladum
+	Old branches dark in color, gray-brown, purple-brown, or dark red; wings not membranous.		(4)
4 (3)	Old branches gray-brown; wings nearly membranous; perianth white.		3 C. aphyllum
+	Old branches dark red or purple-brown; wings subleathery; perianth pink or red.		4 C. rubicundum
5 (2)	Fruit narrowly winged with bristles; bristles flat at base.		(6)
+	Fruit not winged, with bristles on ribs, often not flat at base.		(10)
6 (5)	Wings submembranous, entire; bristles soft, simple or forked at tips, slender, setose.		5 C. cordatum
+	Wings stiffly subleathery, margin narrowing to bristles; bristles stiff, forked at tips, thick.		(7)
7 (6)	Fruit globose or subglobose, densely bristly; achenes coniform.		6 C. densum
+	Fruit ovoid or subglobose, sparsely bristly; achenes ellipsoid, ovoid, or oblong.		(8)
8 (7)	Fruit less than 1.3 cm in diam.; achenes with bristles and wings at base of ribs, unarmed at apex; bristles ca. as long as or shorter than width of achenes; perianth spreading in fruit.		8 C. squarrosum
+	Fruit more than 1.5 cm in diam.; achenes with bristles and wings on entire rib; ca. as long as or longer than width of achenes; perianth reflexed in fruit.		(9)
9 (8)	Fruit dark brown, subglobose; wings 1-2 mm wide.		7 C. colubrinum
+	Fruit yellow or yellowish brown, rarely red-brown, broadly ovoid; wings 2-3 mm wide.		9 C. klementzii
10 (5)	Fruit 1.5-3 cm in diam.		(11)
+	Fruit less than 1.5 cm in diam.		(13)
11 (10)	Fruit globose or subglobose, bristles dense.		20 C. caput-medusae
+	Fruit ovoid or broadly ovoid, bristles sparse.		(12)
12 (11)	Fruit broadly ovoid; achenes ovoid, with 2 or 3 rows of bristles per rib.		15 C. alashanicum
+	Fruit ovoid; achenes ellipsoid, with 2 rows of bristles per rib.		19 C. arborescens
13 (10)	Bristles slender, hair-shaped, breakable or deciduous; fruit ca. 1 mm in diam.		(14)
+	Bristles thick, spiniform; fruit ca. 15 mm in diam.		(16)
14 (13)	Bristles in 1 row; achenes coiled.		13 C. pumilum
+	Bristles in 2 or 3 rows; achenes not coiled.		(15)
15 (14)	Fruit broadly ellipsoid; perianth ovate, spreading in fruit; pedicel 1-2 mm, jointed below.		10 C. mongolicum
+	Fruit subglobose; perianth broadly elliptic, reflexed in fruit; pedicel 2-4 mm, jointed at middle.		18 C. jeminaicum
16 (13)	Bristles in 1 row per rib.		(17)
+	Bristles in 2 or 3 rows per rib.		(18)
17 (16)	Fruit ellipsoid, less than 1 mm in diam.; bristles shorter than width of achenes, branched from middle; pedicel 1-2 mm, jointed near base.		23 C. yengisaricum
+	Fruit broadly ovoid, more than 15 mm in diam.; bristles longer than width of achenes, branched from upper portion; pedicel 3-4 mm, jointed below middle.		22 C. korlaense
18 (16)	Bristles in 3 rows per rib.		(19)
+	Bristles in 2 rows per rib.		(20)
19 (18)	Fruit subglobose, broadly ellipsoid, or ellipsoid; achenes ellipsoid or broadly ellipsoid; pedicel jointed at middle.		12 C. chinense
+	Fruit broadly ovoid or ovoid; achenes ovoid or oblong; pedicel jointed below middle.		16 C. trifarium
20 (18)	Achenes with long beak; ribs often not prominent; bristles sparse, not enlarged at base, soft.		17 C. ebinuricum
+	Achenes without long beak; ribs prominent; bristles dense, enlarged at base, stiff.		(21)
21 (20)	Achenes oblong, not or slightly coiled; bristles in 2 rows at margin of rib.		11 C. gobicum
+	Achenes broadly ovoid or broadly ellipsoid, usually coiled; bristles in 2 rows at middle of rib.		(22)
22 (21)	Bristles slender, breakable; flowers dense.		14 C. zaidamense
+	Bristles thick, stiff; flowers sparse.		21 C. roborowskii