1	Culms very short		(2)
+	Culms long		(3)
2 (1)	Female glumes ovate, rounded at apex.		331 C. radiciflora
+	Female glumes linear-lanceolate, acuminate at apex, scabrous on margins.		332 C. zunyiensis
3 (1)	Nutlets trigonous with angles not constricted at middle		(4)
+	Nutlets trigonous with angles constricted at middle		(18)
4 (3)	Utricles hirsute		(5)
+	Utricles glabrous		(7)
5 (4)	Female spikes usually bearing male flowers at base; utricles rhomboid or obovate.		290 C. chinensis
+	Female spikes without male flowers at base; utricles ovate or lanceolate-ovate		(6)
6 (5)	Utricles lanceolate-ovate, 4.5-5 mm.		291 C. diplodon
+	Utricles ovate, 3-4 mm.		292 C. blinii
7 (4)	Nutlets with transparent grains on surfaces.		304 C. oxyphylla
+	Nutlets without transparent grains on surfaces		(8)
8 (7)	Style slender, base curved.		293 C. qingdaoensis
+	Style base slightly thickened, not curved		(9)
9 (8)	Involucral bracts leaflike, all involucral bracts or lowest one longer than inflorescence		(10)
+	Involucral bracts shortly bladed, shorter than inflorescence		(12)
10 (9)	Spikes 4 or 5, terminal spike linear, sessile.		294 C. manciformis
+	Spikes 2-4, terminal spike linear-cylindric, linear-oblong, or linear, pedunculate		(11)
11 (10)	Spikes 3 or 4, terminal spike male, linear-cylindric, lateral spikes androgynous, male part 1/3-1/2 length of female part.		297 C. austrosinensis
+	Spikes 2-4, terminal spike male, linear or linear-oblong, lateral spikes female, oblong.		298 C. macrandrolepis
12 (9)	Utricles hirsute		(13)
+	Utricles glabrous		(14)
13 (12)	Utricles narrowly rhomboid, 5-6 mm.		299 C. tatsutakensis
+	Utricles oblong, 7-8 mm.		300 C. longerostrata
14 (12)	Leaves 6-10 mm wide		(15)
+	Leaves 1.5-3.5 mm wide		(16)
15 (14)	Leaves subequaling culm, 6-8 mm wide; nutlets with beak erect, base erect stipitate.		301 C. xiphium
+	Leaves surpassing culm, 7-10 mm wide; nutlets with beak curved, base curved stipitate.		303 C. yangshuoensis
16 (14)	Spikes 2, terminal spike clavate, ca. 1 cm, lateral spikes female, ovate, ca. 1 cm, 4- or 5-flowered.		302 C. pseudolongerostrata
+	Spikes 3 or 4, terminal spike cylindric, 3-6 cm, lateral spikes mostly female, ± with male flowers at apex, cylindric, 1.5-4.5 cm, slightly densely flowered		(17)
17 (16)	Leaves 3-5 mm wide; utricle beak 2-toothed; nutlets ovoid, ca. 5 mm.		295 C. simulans
+	Leaves 7-12 mm wide; utricle beak barely 2-toothed; nutlets broadly obovoid, 3.5-4.5 mm.		296 C. austrozhejiangensis
18 (3)	Culms lateral		(19)
+	Culms central		(31)
19 (18)	Nutlets with curved beak		(20)
+	Nutlets with erect beak		(25)
20 (19)	Nutlets with longer beak, ca. 1 mm; female spikes oblong, 1.7-3 cm		(21)
+	Nutlets with shorter beak; female spikes cylindric, 3-7 cm		(22)
21 (20)	Leaf blades, involucral bracts, and sheaths scabrous; involucral bracts leaflike, longer than spike; female glumes pale brown, green 3-veined scabrous costa excurrent into a long awn at obtuse apex.		305 C. shangchengensis
+	Leaf blades, involucral bracts, and sheaths glabrous; involucral bracts shortly bladed, shorter than spike; female glumes yellow-white, green 3-veined glabrous costa excurrent into a mucro at emarginate apex.		306 C. manca
22 (20)	Female spikes rather thick, ca. 15 mm wide; utricles subglobose.		307 C. nanchuanensis
+	Female spikes rather slender, 7-11 mm wide; utricles ovate		(23)
23 (22)	Lateral spikes androgynous, usually male part equaling female part, densely flowered.		310 C. thibetica
+	Lateral spikes mostly female with male flowers at apex, male part shorter than female part		(24)
24 (23)	Female spikes sparsely flowered, horizontally patent at maturity.		308 C. heudesii
+	Female spikes densely flowered, obliquely patent at maturity.		309 C. taipaishanica
25 (19)	Female spikes only 1; female glumes ovate, costa projecting beyond apex forming a long awn.		311 C. funingensis
+	Female spikes 3-5; female glumes ovate or ovate-oblong, obtuse or rounded at apex, green 3-veined costa projecting beyond apex forming a mucro or cusp but rarely an awn		(26)
26 (25)	Female spikes cylindric; nutlets with cylindric beak annulate at orifice		(27)
+	Female spikes ovate or oblong; beak of nutlets not thickened or slightly thickened but not annulate at orifice		(29)
27 (26)	Female spikes spaced, sparsely flowered; female glumes with a mucro at apex; utricles puberulent.		314 C. longqishanensis
+	Female spikes approximate, densely flowered; female glumes awned or cuspidate at apex; utricles glabrous		(28)
28 (27)	Female glumes awned at apex; terminal spike male, linear-cylindric, 4.5-8 cm.		312 C. harlandii
+	Female glumes cuspidate at apex; terminal spike male, linear 1.5-3 cm.		313 C. hoozanensis
29 (26)	Utricles puberulent.		306 C. manca
+	Utricles glabrous		(30)
30 (29)	Culms 25-40 cm tall; leaf blades 4-6 mm wide.		315 C. hastata
+	Culms 7-13 cm tall; leaf blades 10-15 mm wide.		316 C. kaoi
31 (18)	Culms, leaves, involucral bracts, female glumes, and utricles all puberulent		(32)
+	Culms, leaves, involucral bracts, and female glumes all glabrous		(33)
32 (31)	Beak of nutlets erect; female spikes 3, bearing a short male part at apex; leaf blades 6-10 mm wide.		317 C. pseudolaticeps
+	Beak of nutlets curved; female spikes 1 or 2; leaf blades 3-5 mm wide.		318 C. laticeps
33 (31)	Female glumes linear-lanceolate or ovate-lanceolate, usually acuminate at apex, rarely awned		(34)
+	Female glumes ovate, oblong-ovate, or oblong, obtuse, rounded, or truncate at apex, green 1- or 3-veined costa projecting beyond apex forming a mucro or long awn		(38)
34 (33)	Female glumes brown		(35)
+	Female glumes pale green or pale yellow		(36)
35 (34)	Female glumes linear-lanceolate; lateral spikes usually female, occasionally becoming androgynous, male part shorter than female part; style base not thickened.		329 C. brevicuspis
+	Female glumes ovate-lanceolate; lateral spikes usually female, occasionally becoming androgynous, male part longer than or equaling female part; style base thickened.		330 C. kuchunensis
36 (34)	Beak of nutlets curved; female glumes slightly longer than or equaling utricle.		326 C. cheniana
+	Beak of nutlets erect; female glumes shorter than utricle		(37)
37 (36)	Culms up to ca. 65 cm tall; leaf blades 8-10 mm wide; lateral spikes cylindric, ca. 6.5 × 1 cm.		327 C. saxicola
+	Culms 2-10 cm tall; leaf blades 1.5-2.5 mm wide; lateral spikes oblong-cylindric, ca. 1.2 × 0.6 cm.		328 C. lianchengensis
38 (33)	Beak of nutlets short and curved, annulate at orifice, style base thickened; leaf blades abruptly contracted into a cusp at apex.		319 C. liqingii
+	Beak of nutlets long and erect, rarely short, annulate or not at orifice, style base hardly thickened; leaf blades not contracted into a cusp at apex		(39)
39 (38)	Nutlets shallowly constricted on angles at middle, beak short; leaf blades papery.		320 C. rhynchophora
+	Nutlets deeply constricted on angles at middle, beak ca. 1 mm or more; leaf blades leathery		(40)
40 (39)	Female glumes ovate, acute or mucronate at apex, red-brown; nutlets constricted on angles and concave surfaced.		321 C. calcicola
+	Female glumes oblong, obtuse or emarginate at apex, green 3-veined costa excurrent into an awn, brown; nutlets constricted only on angles at middle		(41)
41 (40)	Spikes 2, lateral spike wholly female.		325 C. putuoensis
+	Spikes 3 or 4, lateral spikes female or androgynous with male part up to 1/2 length of spike		(42)
42 (41)	Nutlets rhomboid.		322 C. tenebrosa
+	Nutlets obovoid or ovoid-ellipsoid		(43)
43 (42)	Nutlets ovoid-ellipsoid; female glumes with awn ca. 3.5 mm.		323 C. chaofangii
+	Nutlets broadly obovoid; female glumes with awn ca. 5 mm.		324 C. wahuensis