Tribe 3. CYPEREAE Nees, Linnaea 9: 282. 1834. [Draft]

莎草族 suo cao zu

                Rhizome present or absent. Culms triquetrous, rarely cylindric. Leaves graminiform, basalmost sheaths usually bladeless. Bracts leaf-shaped. Anthela terminal, simple or compound, with several to many first order or second order rays; rays long or short. Spikelets 2 to many in spikes, digitate or capitate at apex of rays, rarely single; rachilla not articulate, only articulate at base, or articulate at base of each scale, usually deciduous at articulation, winged or wingless; scales distichous, alternate, rarely spirally arranged, gradually deciduous from base to apex or persistent at rachilla and deciduous with rachilla; basalmost 2 scales usually without flower; remaining scales each with a bisexual flower. Flowers without hypogynous bristles or scalelike perianth parts. Stamens 1--3; connective usually prominent on apex of anther, sometimes laxly bristly. Style base not swollen; stigmas 1--3. Achene trigonous or biconvex, not stipitate or very shortly stipitate, surface smooth, various striate, or puncticulate.

                Seven genera and 76 species (13 endemic) in China.

1a. Rachilla not articulate; spikelets not deciduous.

2a. Stigmas 3; achene trigonous ...............................................................................................................................  22. Cyperus

2b. Stigmas 2; achene biconvex, plano-convex, or concave-convex.

3a. Achene dorsiventrally compressed, borne with side toward rachilla .........................................................  23. Juncellus

3b. Achene compressed when mature, borne with margin toward rachilla .........................................................  24. Pycreus

1b. Rachilla articulate; scales persistent on rachilla, rarely deciduous, usually deciduous with rachilla.

4a. Rachilla many-articulate not only at base ....................................................................................................  28. Torulinium

4b. Rachilla articulate at base.

5a. Stigmas 2; achene biconvex, borne with margin toward rachilla ...................................................................  27. Kyllinga

5b. Stigmas 3; achene trigonous, borne with side toward rachilla.

6a. Spikelets terete to subterete; keel on dorsum of scale without wing ..........................................................  25. Mariscus

6b. Spikelets very compressed; keel on dorsum of scale with wing .............................................................  26. Courtoisina

22. CYPERUS Linnaeus, Sp. Pl. 1: 44. 1753.

莎草属 suo cao shu

Dai Lunkai (戴伦凯)

                Herbs, annual or perennial. Rhizome stoloniferous or only rooted, rarely tuberous. Culms caespitose or solitary, erect, usually trigonous or acutely triquetrous, sometimes compressed triquetrous, stout or slender, leaved at basal part or at base. Leaves long or shortly sheathed. Bracts leaf-shaped, usually 2--10(--20 or more), at base of inflorescence. Anthela terminal, simple or compound, sometimes shorten into a head, with several to many rays and raylets; rays and raylets unequal or rarely equal in length. Spikelets few to many in spikes, digitate or capitate at apex of rays, rarely single; rachilla not articulate at base, persistent, usually with narrow wings; scales distichous, rarely spirally arranged; basalmost 1 or 2 scales without a flower; remaining scales each with a bisexual flower. Flowers without hypogynous bristles or scalelike perianth parts. Stamens (1--)3. Style base not swollen; stigmas (2 or)3, deciduous at maturity. Achene trigonous, surface smooth, puncticulate, tuberculate, or rarely reticulately striate.

                About 600 species: temperate, subtropics, and tropics worldwide; 43 species (seven endemic and two cultivated) in China.

1a. Spikelets digitate or fascicled on a very abbreviated rachis (subgen. Pycnostachys).

2a. Anthela with very abbreviated rays, rarely with few slightly long rays.

3a. Culms usually tall; spikelets several to more than 20, slightly lax; scales conspicuously distichous, ca. 4 mm, apex obtuse and muticous (sect. Platystachyi).

4a. Leaves usually longer than culm; spikelets 5--8 mm, 6--10-flowered .............................................  38. C. szechuanensis

4b. Leaves usually shorter than culm; spikelets 7--25 mm, 8--48-flowered .......................................................  39. C. niveus

3b. Culms dwarf; spikelets numerous, very densely arranged; scales spirally arranged or obscurely distichous, ca. 2 mm, apex recurved mucronate (sect. Dichostylis).

5a. Spikelets ovoid to lanceolate, 3--4 X ca. 1.5 mm; scales spirally arranged .......................................  40. C. michelianus

5b. Spikelets oblong-lanceolate or oblong, rarely lanceolate, 3--8 X 1.5--2 mm; scales obscurely distichous.

6a. Spikelets very numerous, congested into capitulum, 4--5 mm; scales oblong-lanceolate, apex slightly long mucronate; stigmas 2, sometimes 3; achene narrowly oblong to lanceolate oblong, nearly trigonous .............  41. C. pygmaeus

6b. Spikelets many, congested at abbreviated or slightly elongate rays, 3--8 mm; scales ovate or broadly ovate, apex short mucronate; stigmas 2; achene ellipsoid, plano-convex.

7a. Anthela with very abbreviated rays, many spikelets congested into capitulum; spikelets 3--8 mm; scales broadly ovate ......................................................................................................................................................................  42. C. nipponicus

7b. Anthela simple, with 3--6 rays, mostly to 6 cm, many spikelets congested at apex of rays; spikelets 4--6 mm; scales ovate ......................................................................................................................................................  43. C. shandongense

2b. Anthela with long rays.

8a. Perennial herb; rhizome short, lignous; scales ca. 2 mm; achene 0.7--1.5 mm.

9a. Spikelets slightly turgid; scales many-veined (sect. Diffusi) ......................................................................  29. C. diffusus

9b. Spikelets compressed; scales 3--5-veined.

10a. Culms obtusely trigonous to nearly terete, with bladeless sheaths at basal part; leafy bracts 15--20, nearly equal in length (sect. Vaginati) ............................................................................................................................ 27. C. alternifolius

10b. Culms compressed triquetrous, with leaves at basal part; leafy bracts 5--12, unequal in length (sect. Pseudanosporum) ........................................................................................................................................................................  28. C. platystylis

8b. Annual herb, rarely perennial herb; scales ca. 1(--1.5) mm; achene 0.2--0.3 mm.

11a. Leaves very narrow, involute on both margins, canaliculated on middle adaxial side; scales papery, apex truncate and recurved awned; achene oblong-obovoid to oblong (sect. Amabiles) .............................................  37. C. cuspidatus

11b. Leaves flat; scales membranous, apex obtuse and mucronate or muticous; achene obovoid or ellipsoid.

12a. Perennial herb, rarely annual herb; culms with few leaves or with bladeless sheaths only; stamens (1--)3; achene less than 1/2 as long as scales (sect. Haspani).

13a. Leafy bracts usually longer than inflorescence; scales laxly arranged, with recurved apex; anther apex not white setose; achene ca. 0.2 mm .........................................................................................................................  35. C. tenuispica

13b. Leafy bracts usually shorter than inflorescence; scales densely imbricate, apex straight; anther apex white setose; achene ca. 0.5 mm .............................................................................................................................................  36. C. haspan

12b. Annual herb, without stolon (except C. duclouxii); culms usually bladed; stamens 1 or 2(or 3); achene 1/2 or more as long as scale (sect. Fusci).

14a. Perennials, with stolon; culms scattered; spikelets 3--10, digitately arranged ...................................  30. C. duclouxii

14b. Annuals, with fibrous roots; culms tufted; spikelets many, congested into a capitulum.

15a. Spikelets numerous, densely congested into densely capitulum; scales compressed rotund ..........  34. C. difformis

15b. Spikelets several to more than 10, congested into laxly capitulum.

16a. Scales lax, rotund-ovate to subrotund, spreading when mature, apex mucronate .........................  31. C. nigrofuscus

16b. Scales slightly densely, not spreading at maturity, broadly ovate or compressed rotund, apex muticous.

17a. Spikelets ca. 1.5 mm wide; scales broadly ovate, purplish brown to brown, between both lateral veins yellowish green ................................................................................................................................................................................  32. C. fuscus

17b. Spikelets ca. 1.8 mm wide, scales compressed rotund, blackish purple ................................................  33. C. nanellus

1b. Spikelets in a spike at apical part of rays (subgen. Cyperus).

18a. Rachilla winged; style usually long or medium, rarely short.

19a. Spikes cylindric in outline, with numerous spikelets.

20a. Spikelets linear, terete or subterete, rachilla slightly broadly winged, wings lanceolate, deciduous; spikelets nearly distichous, laxly arranged, nearly level spreading, ca. 1 cm (sect. Fastigiati).

21a. Spikes broadly cylindric in outline, 1.5--2 cm wide, spikelets level spreading; connective of anthers not prominent at anther apex .......................................................................................................................................................  1. C. digitatus

21b. Spikes narrowly cylindric in outline, 0.8--1.2 cm wide, spikelets obliquely spreading to nearly erect; connective of anthers prominent and subulate at anther apex ...............................................................................................  2. C. elatus

20b. Spikelets oblong-lanceolate, compressed, rachilla narrowly winged, wings linear, persistent (sect. Exaltati).

22a. Spikes ± peduncled; spikelets nearly distichous, laxly arranged; scales straight-mucronate at apex; anthers linear ............................................................................................................................................................................  3. C. exaltatus

22b. Spikes not peduncled; spikelets polystichous, densely arranged; scales recurved mucronate or straight-mucronate at apex; anthers oblong.

23a. Leafy bracts 8--15; anthela with 12--15 rays; spikes 1.5--11 cm; scales oblong-obovate, 2.2--2.5 mm, apex straight mucronate; achene oblong to obovoid-oblong ......................................................................................  4. C. simaoensis

23b. Leafy bracts 3--5; anthela with 6--10 rays; spikes 1.5--4 cm; scales broadly ovate, ca. 1.5 mm, apex curved mucronate; achene obovoid to ellipsoid .......................................................................................................................  5. C. imbricatus

19b. Spikes broadly ovate, turbinate, elliptic, oblong, or rotund in outline, rarely cylindric, with several to more ten spikelets, rarely with numerous spikelets (e. g. C. glomeratus and C. eleusinoides).

24a. Rhizome abbreviated or surculose, without stolon and tuber; scales lax.

25a. Culms slender; spikes broadly ovate in outline; spikelets subquadrangular, obliquely to level spreading at maturity; scales ca. 4 mm (sect. Subquadrangulares) ........................................................................................  13. C. tenuiculmis

25b. Culms stout; spikes oblong, cylindric, ellipsoid, or globose, rarely broadly ovate in outline; spikelets slightly compressed, nearly erect, rarely level spreading; scales ca. 2 mm (sect. Distantes).

26a. Spikelets laxly arranged, level spreading after anthesis, 0.8--4 cm X ca. 1 mm; scales dark blood red  14. C. distans

26b. Spikelets densely or very densely arranged, nearly erect, not level spreading after anthesis, 0.4--1.1 cm X 1.5--2 mm; scales reddish brown or yellowish brown.

27a. Annuals; without rhizome, with fibrous roots; spikes very dense, with numerous spikelets; scales muticous at apex ......................................................................................................................................................................  17. C. glomeratus

27b. Perennials; rhizome abbreviated; scales mucronate at apex.

38a. Raylets of anthela radially spreading; spikes slightly lax, with many spikelets, sometimes slightly nutant  15. C. nutans

28b. Raylets of anthela suberect; spikes dense, with numerous spikelets, not nutant .......................  16. C. eleusinoides

24b. Rhizome repent or with stolons and tubers; scales ± densely imbricate.

29a. Culms stout, sheathed, bladeless or apicalmost 1 with short blade only; scales oblong, concave, margin involute; spikelets slightly compressed, rachilla with reddish brown wings (sect. Brevifoliati) .......................  6. C. pangorei

29b. Culms slightly slender; sheaths bladed; scale ovate, broadly ovate or ovate-elliptic, margin not involute.

30a. Spikes ovate in outline; scales laxly imbricate, spreading at maturity; tubers globose to ovoid (sect. Cyperus)  12. C. esculentus

30b. Spikes broadly ovate or obdeltoid in outline; scales densely imbricate, not spreading at maturity, rarely slightly laxly imbricate and spreading at maturity (sect. Rotundi).

31a. Rachilla narrowly winged; scales laxly imbricate, spreading at maturity; bracts subulate, shorter than inflorescence .......................................................................................................................................................................  11. C. tenuifolius

31b. Rachilla broadly winged; scales densely imbricate, not spreading at maturity; bracts leaf-shaped, usually longer than inflorescence.

32a. Leaves and bracts slightly narrow, usually plicate; rays of anthela erect or suberect, less than 2 cm.

33a. Stolons short; culms laxly tufted; rays of anthela erect; spikelets laxly arranged into spikes, linear, ca. 1 mm wide; anthers ellipsoid; achene oblong ...................................................................................................  7. C. linearispiculatus

33b. Stolons long; culms scattered; rays of anthela slightly obliquely spreading; spikelets nearly digitately arranged at apex of ray, oblong-lanceolate to lanceolate, 2--3 mm wide, slightly turgid; anthers linear; achene obovoid to ellipsoid .......................................................................................................................................................................  8. C. stoloniferus

32b. Leaves and bracts slightly broad, usually flat; rays of anthela obliquely spreading, slender, mostly to 12 cm.

34a. Scales dark blood red, ovate to oblong-ovate ............................................................................................. 9. C. rotundus

34b. Scales straw-colored to brownish yellow, broadly ovate to elliptic ....................................................  10. C. tuberosus

18b. Rachilla not winged or only with very narrowly and white hyaline margins; style short.

35a. Perennials, with long stolons; spikelets slightly turgid; scales not keeled on dorsum, rarely keeled, margin involute, apex obtuse or rotund and usually muticous or rarely mucronate (sect. Proceri).

36a. Culms with long sheaths at basal part, sheaths with short blade or nearly bladeless. Rachis of spikes glabrous; spikelets linear; scales elliptic to oblong .............................................................................................  18. C. malaccensis

36b. Culms with long blades; rachis of spikes yellow hispidulous, rarely glabrous; spikelets lanceolate; scales ovate or broadly ovate.

37a. Rachis of spikes laxly hispidulous, sometimes glabrous; spikelets ca. 3 mm wide; scales obtuse-rotund and muticous at apex .............................................................................................................................................................  20. C. procerus

37b. Rachis of spikes slightly densely hispidulous; spikelets 1.5--2.5 mm wide; scales mucronate or muticous at apex.

38a. Anthela compound; scales with inconspicuous keel and not spinulate .................................................  19. C. pilosus

38b. Anthela simple; scales with conspicuous keel and spinulate ...............................................................  21. C. babakan

35b. Annuals, without rhizome and stolon, with fibrous roots only; spikelets ± compressed; scales keeled on dorsum, margin not involute, apex mucronate.

39a. Rachis of spikes abbreviated; spikelets densely arranged, nearly capitate; scales densely imbricate; achene ca. 1/2 as long as scales; spikelets compressed; scales pale to straw-colored, sometimes with rust brown short striae (sect. Compressi) .................................................................................................................................................  26. C. compressus

39b. Rachis of spikes long; spikelets laxly arranged; scales lax; achene nearly as long as scale (sect. Iriae).

40a. Anthela compound; spikelets erect or obliquely spreading.

41a. Rachilla not winged; scales retuse and very short mucronate at apex ...........................................................  22. C. iria

41b. Rachilla with white hyaline and narrow margins; scales rotund and slightly long mucronate at apex  23. C. microiria

40b. Anthela simple; spikelets nearly level spreading.

42a. Rachis of spikes glabrous; scales reddish brown, apex slightly recurved mucronate .......................  24. C. amuricus

42b. Rachis of spikes white hispidulous on angles; scales dark blood red, apex rotund and muticous  25. C. orthostachyus

I. Cyperus subgen. Cyperus

莎草亚属 suo cao ya shu

Cyperus subgen. Choristachys C. B. Clarke; C. subgen. Eucyperus (Grisebach) C. B. Clarke pars. choristachys Kükenthal.

                Spikelets arranged into spikes at apical part of rays; rachis long, rarely ± short.

1. Cyperus subgen. Cyperus sect. Fastigiati Kükenthal in Engler, Das Pflanzenreich IV. 20(Heft 101): 53. 1935.

多辐射枝组 duo fu she zhi zhu

                Rhizome very short. Culms stout, trigonous or rarely triquetrous, basal part foliate. Leaf blade ± broad, flat. Bracts longer than inflorescence. Anthela compound, with many rays. Spikelets numerous, in cylindric spikes, nearly erect or ± level spreading, quadrifarious or nearly distichous, linear-terete or subcompressed and angular; rachilla wings broadly lanceolate, early deciduous; scales densely imbricate. Stamens 3; anthers linear. Style long; stigmas 3, slender.

                Two species in China.

1. Cyperus digitatus Roxburgh, Fl. Ind., ed. 1820, 1: 205. 1820.

长小穗莎草 chang xiao sui suo cao

                Rhizome ligneous, very short. Culms tufted, 50--150 cm tall, stout, triquetrous, smooth, foliate at basal part. Leaves nearly as long as culm; leaf blade 4--15 mm wide, flat or conduplicate, subcoriaceous, purplish brown long sheathed. Bracts leaflike, 5--7, longer than inflorescence. Anthela compound or decompound; rays 6--10, usually to 18 cm, each with 4--7 raylets; raylets unequal in length. Spikes at apical part of raylets, cylindric, 3--6 X 0.4--2 cm, without a peduncle and with many laxly arranged spikelets. Spikelets nearly distichous, linear or lanceolate, 3--12 X 1--1.5 mm, slightly compressed or compressed, level or obliquely spreading, 4--40-flowered; rachilla winged, wings lanceolate; scales straw-colored, reddish brown, or golden-yellow on both surfaces, densely imbricate, ovate to elliptic, keel greenish, veins 3--5, apex mucronate. Stamens 3; anthers yellow, linear; connective not prominent above anther apex. Style long; stigmas 3, exerted from scale. Achene dark gray at maturity, oblong-ellipsoid, 1/2--3/5 as long as scale, trigonous, puncticulate. Fl. Jul--Oct, fr. unknown.

                Open areas in forests; wet places; low elevations to 1800 m. Guangxi, Taiwan, Yunnan [India, Indonesia, Nepal, New Guinea, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; tropical Africa, America, and Australia].

1a. Spikes 1.5--2 cm wide; spikelets linear, 10--12 mm, level spreading, 10--40-flowered ........................  1a. var. digitatus

1b. Spikes 0.4--1.2 cm wide; spikelets lanceolate, 3--6 mm, obliquely spreading, 4--10-flowered.

2a. Spikes 5--12 mm wide; spikelets slightly compressed, 3--6 mm, 6--10-flowered ........................  1b. var. pingbienensis

2b. Spikes 4--8 mm wide; spikelets compressed, ca. 4 mm, 4--6-flowered .................................................  1c. var. laxiflorus

1a. Cyperus digitatus var. digitatus

长小穗莎草 chang xiao sui suo cao

                Spikes 1.5--2 cm wide. Spikelets linear, 10--12 mm, 10--40-flowered, level spreading. Fl. unknown, fr. unknown.

                Wet places; low elevations. Guangxi, Taiwan, Yunnan [India, Indonesia, Malaysia, Nepal, New Guinea, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; tropical Africa, America, and Australia].

1b. Cyperus digitatus var. pingbienensis L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 230. 1961.

屏边莎草 bing bian suo cao

                Spikes 0.5--1.2 cm wide; spikelets lanceolate, 3--6 mm, slightly compressed, obliquely spreading, 6--10-flowered. Fl. Sep--Oct, fr. unknown.

                * Wet places; ca. 1500 m. Yunnan (Pingbian Xian).

1c. Cyperus digitatus var. laxiflorus L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 230. 1961.

少花穗莎草 shao hua sui suo cao

                Spikes 0.4--0.8 cm wide. Spikelets ovoid-lanceolate, ca. 4 mm, compressed, obliquely spreading, 4--6-flowered. Fl. Jul--Aug, fr. unknown.

                * Open areas in forests; ca. 1800 m. Yunnan (Menghai Xian).

2. Cyperus elatus Linnaeus, Cent. Pl. II. 5. 1756.

黄翅莎草 huang chi suo cao

                Herbs, perennial. Rhizome short, slightly thick, lignous. Culms laxly caespitose, to 3 m tall, stout, smooth, basally nearly terete, apically trigonous. Leaves basal, nearly as long as culm; sheath purple sheath; leaf blade 8--12 mm wide, flat subcoriaceous, midvein and margin scabrous. Bracts 5--8, leaflike, longer to shorter than inflorescence. Anthela decompound; rays 4--10, to 25 cm, unequal in length, each with 4--7 raylets; raylets usually to 8 cm, apex with 3--5 spikes. Spikes cylindric, 3--6 X 0.8--1.2 cm, suberect to obliquely spreading, with many spikelets. Spikelets linearly cylindric, 4--7 X ca. 1 mm, obliquely spreading to nearly erect, 10--14-flowered; rachilla wings yellow, lanceolate, easily deciduous; scales yellowish to golden-yellow on both surfaces but middle green, densely imbricate, oblong to elliptic, ca. 1.5 mm, veins 3--5, apex mucronate. Stamens 3; anthers oblong, ca. 1.5 mm; connective prominent, subulate above apex of anther, prominent part ca.1/3 as long as anther, apex setose. Style slender; stigmas 3. Achene dark gray at maturity, oblong-ellipsoid, ca.1/2 as long as scale, densely puncticulate. Fl. Jul--Aug.

                Habitat and elevation unknown. Hainan [Cambodia, India, Indonesia, Laos, Malaysia, New Guinea, Philippines, Thailand, Vietnam; Pacific Islands].

2. Cyperus subgen. Cyperus sect. Exaltati Kunth, Enum. Pl. 2: 70. 1837.

高稈莎草组 gao gan suo cao zu

                Rhizome very short. Culms tall, stout. Leaf blade ± broad, flat. Bracts longer than inflorescence. Anthela decompound or compound, with many rays. Spikes cylindric, peduncled or sessile, with many spikelets. Spikelets nearly distichous or polystichous, linear-lanceolate to oblong-lanceolate, compressed, obliquely spreading, level spreading after anthesis; rachilla wings linear to linear-oblong, narrow, persistent; scales densely imbricate, keeled, apex mucronate. Stamens (2 or)3; anthers linear to linear-oblong; connective slightly prominent. Style slender; stigmas (2 or)3, ± short.

                Two species in China.

3. Cyperus exaltatus Retzius, Observ. Bot. 5: 11. 1788.

高稈莎草 gao gan suo cao

                Rhizome short, with many fibrous roots. Culms 100--150 cm tall, stout, trigonous, smooth, basally with leaves. Leaves nearly as long as culm; sheath purplish brown, long; leaf blade 6--10 mm wide, margin scabrous. Bracts 3--6, basal ones longer than inflorescence. Anthela compound or decompound; rays 5--10, to 18 cm, unequal in length, each with several raylets. Spikes 1--3 at raylet apex, cylindric or narrowly cylindric, 2--5 cm X 2.5--10 mm, with many spikelets. Spikelets nearly distichous, densely to laxly arranged, oblong-lanceolate, 2--6 X 1--1.5 mm, compressed, obliquely spreading, 4--25-flowered; rachilla wings white, linear, narrow, hyaline; scales dark grayish brown or yellowish brown, slightly densely imbricate, ovate to subobovate, ca. 1.5 mm, slightly nitid, keel green, veins 3--5, apex strict mucronate. Stamens 3; anthers linear; connective prominent above apex of anther. Style slender; stigmas 3. Achene obovoid or ellipsoid, less than 1/2 as long as scale, trigonous, smooth. Fl. and fr. Jun--Nov.

                Grasslands, pond margins, sandy soil, moist or wet places; 500--1100 m. Anhui, Fujian, Guangdong, Guizhou, Hainan, Jiangsu, Shandong, Taiwan, Zhejiang [Bangladesh, India, Indonesia, Japan, Malaysia, Myanmar, New Guinea, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; tropical Africa, America, and Australia].

                Culms are used for making mats.

1a. Spikes narrowly cylindric, 2--4 cm X 2.5--4 mm; spikelets ± densely arranged, 2--3 mm, 4--6-flowered ...........  3d. var. tenuispicatus

1b. Spikes cylindric, 2--5 cm X 7--10 mm; spikelets 4--6 mm, 6--25-flowered.

2a. Spikelets laxly arranged, 3--6 mm, 6--16-flowered.

3a. Spikelets slightly laxly arranged, 4--6 mm, 6--16-flowered .....................................................................  3a. var. exaltatus

3b. Spikelets very laxly arranged, 3--4 mm, 6--8-flowered .......................................................................  3b. var. hainanensis

2b. Spikelets very densely arranged, to 14 mm, 12--25-flowered ..........................................................  3c. var. megalanthus

3a. Cyperus exaltatus var. exaltatus

高稈莎草 gao gan suo cao

                Spikes cylindric, 2--5 cm X 7--10 mm. Spikelets slightly laxly arranged, 4--6 X 1--1.5 mm, 6--16-flowered. Fl. and fr. Jun--Aug.

                Moist or wet places; elevation unknown. Fujian, Guangdong, Hainan, Jiangsu Taiwan [Bangladesh, India, Indonesia, Japan, Malaysia, Myanmar, New Guinea, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; tropical Africa, America, and Australia].

3b. Cyperus exaltatus var. hainanensis L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 230. 1961.

海南高稈莎草 hai nan gao gan suo cao

                Spikelets very laxly arranged, 3--4 X ca. 1 mm, 6--8-flowered. Fl. Aug.

                * Grasslands, pond margins, sandy soil; elevation unknown. Hainan.

3c. Cyperus exaltatus var. megalanthus Kükenthal, Repert. Spec. Nov. Regni Veg. 27: 107. 1929--1930.

长穗高稈莎草 chang sui gao gan suo cao

                Spikelets very densely arranged, to 1.4 cm, 12--25-flowered. Fl. and fr. Sep--Nov.

                * Moist places; elevation unknown. Anhui, Fujian, Jiangsu, Zhejiang.

3d. Cyperus exaltatus var. tenuispicatus L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 230. 1961.

广东高稈莎草 guang dong gao gan suo cao

                Anthela decompound. Spikes narrowly cylindric, 2--4 cm X 2.5--4 mm. Spikelets ± densely arranged,

oblong, 2--3 mm, 4--6-flowered. Fl. Sep.

                * Habitat and elevation unknown. Guangdong.

4. Cyperus simaoensis Y. Y. Qian, Bull. Bot. Res., Harbin 21: 335. 2001.

思茅莎草 si mao suo cao

                Rhizome short, with many fibrous roots. Culms tufted, 70--130 cm tall, stout, obtusely trigonous, smooth, with 3--5 leaves, basally enclosed by leaf sheaths. Leaves shorter than culm; sheath reddish brown but base dark brown, 10--35 cm; leaf blade 0.8--1.2 cm wide, base folded, apically flat. Bracts 8--15, leaf-shaped, mostly to 125 cm, usually longer than inflorescence. Anthela compound; rays 12--15, mostly to 25 cm, unequal in length, usually 8--12 each with 2--11 raylets; raylets radially spreading. Spikes cylindric, 1.5--11 X 0.7--1.3 cm, with numerous spikelets, usually not peduncled, rarely peduncled. Spikelets in 3--5 rows, densely arranged, oblong-lanceolate, 4--8 X 1--1.5 mm, obliquely spreading, 4--10-flowered; rachilla wings white, narrow, hyaline, persistent; scales brownish yellow on both surfaces, densely imbricate, oblong-obovate, 2.2--2.5 mm, slightly nitid, veins 3--5 but obscure, midvein forming a greenish keel, apex straight mucronate. Stamens 3; anthers oblong. Style long; stigmas 3. Achene narrowly ellipsoid to sometimes nearly obovoid, 1.2--1.3 mm, trigonous, smooth.

                * River margins; ca. 1200 m. Yunnan.

5. Cyperus imbricatus Retzius, Observ. Bot. 5: 12. 1788.

迭穗莎草 die sui suo cao

Cyperus mediorubescens Hayata; C. radiatus Vahl.

                Rhizome short, with many fibrous roots. Culms 70--150 mm tall, stout, obtusely trigonous, smooth, basally clothed by several leaf sheaths. Leaves basal, shorter than culm; sheath reddish brown to dark brown, long; leaf blade 0.5--1.5 cm wide, basally plicate, apically flat. Bracts 3--5, longer than inflorescence. Anthela compound; rays 6--10, to 16 cm, unequal in length, each with 3--10 raylets; raylets radially spreading. Spikes 3--6 fasciculate at apex of raylet, sessile or subsessile, densely arranged, cylindric, 1.5--4 X 0.6--1.4 cm, with many spikelets. Spikelets polystichous, lanceolate to oblong-lanceolate, 4--12 X 1.5--2 mm, obliquely spreading, slightly compressed, 8--30-flowered; rachilla wings white, narrow, hyaline, persistent; scales brownish yellow to straw-colored, densely imbricate, ovate to broadly ovate, ca. 1.5 mm, nitid, keel greenish ending in a recurved mucro, veins 3--5. Stamens 3; anthers oblong; connective prominent above anther apex. Style long; stigmas 3. Achene obovoid to subellipsoid, ca. 1/2 as long as scale, trigonous, smooth. Fl. and fr. Sep--Oct.

                Shallow water in ponds, shady moist places; elevation unknown. Guangdong, Hainan, Taiwan [Afghanistan, India, Japan, Malaysia, Myanmar, Nepal, Thailand, Vietnam; tropical Africa, America, and Asia, Madagascar].

1a. Spikes 6--10 mm wide; spikelets 4--6 mm, 8--20-flowered ....................................................................  5a. var. imbricatus

1b. Spikes 12--14 mm wide; spikelets 8--12 mm, 24--30-flowered ...............................................................  5b. var. elongatus

5a. Cyperus imbricatus var. imbricatus

迭穗莎草 die sui suo cao

                Anthela rays to 12 cm. Spikes 6--10 mm wide. Spikelets 4--6 mm, 8--20-flowered. Fl. and fr. Sep--Oct.

                Shallow water in ponds, shady moist places; elevation unknown. Guangdong, Hainan, Taiwan [Afghanistan, India, Japan, Malaysia, Myanmar, Nepal, Vietnam; tropical Africa and America, Madagascar].

                Culms are used for making mats.

5b. Cyperus imbricatus var. elongatus (Boeckeler) L. K. Dai, stat. nov.

大密穗莎草 da mi sui suo cao

Cyperus radiatus Vahl var. elongatus Boeckeler, Linnaea 36: 319. 1870; C. densespicatus Hayata; C. imbricatus var. densespicatus (Hayata) Ohwi; C. imbricatus subsp. elongatus (Boeckeler) T. Koyama.

                Anthela rays to 16 cm. Spikes 12--14 mm wide. Spikelets 8--12 mm, 24--30-flowered. Fr. Oct.

                Wet places; elevation unknown. Taiwan [tropical Africa and Asia].

3. Cyperus subgen. Cyperus sect. Brevifoliati C. B. Clarke in J. D. Hooker, Fl. Brit. India 6: 611. 1893.

短叶莎草组 duan ye suo cao zu

                Rhizome repent. Culms tall, stout, trigonous to subterete. Leaves bladeless or apicalmost sheath with a short leaf blade. Bracts leaf-shaped, ± short. Anthela compound or decompound, rarely simple, with many rays. Spikes broadly ovoid to turbinate. Spikelets slightly densely to laxly arranged, linear, slightly compressed, erect to obliquely spreading; rachilla wings lanceolate to oblong, persistent; scales ± laxly imbricately, not keeled, veins many. Stamens 3; anthers linear; connective prominent. Style long; stigmas 3.

                One species in China.

6. Cyperus pangorei Rottboell, Descr. Pl. Rar. 18. 1772.

红翅莎草 hong chi suo cao

                Rhizome slightly short, transversely repent. Culms 50--90 cm tall, stout, obtusely trigonous, smooth. Leaves basally with a brown long sheath, apically bladeless or with a short blade. Bracts 3--5, leaf-shaped, longer than inflorescence. Anthela decompound or compound; rays 5--7, to 5 cm, unequal, each with 3--8 raylets. Spikes broadly ovate in outline, 1--2 X 1--2 cm, with 4--15 spikelets. Spikelets ± laxly arranged, linear, 8--20 X ca. 1.5 mm, slightly compressed, obliquely spreading, 6--30-flowered; rachilla wings reddish brown, linear-oblong; scales reddish brown on both surfaces but middle green, lax, oblong, 2--3 mm, papery, not keeled, veins 3--5, margin slightly revolute at maturity, apex obtuse to rounded. Stamens 3; anthers linear; connective prominent above anther, apex sometimes setiferous. Style medium length; stigmas 3. Achene dark brown, obovoid-oblong, ca. 1/2 as long as scale, trigonous, densely puncticulate. Fl. and fr. Nov--Jan.

                River margins, water margins; elevation unknown. Hainan, Hunan, Sichuan [Bhutan, India, Myanmar, Nepal, Pakistan, Sri Lanka, Vietnam].

4. Cyperus subgen. Cyperus sect. Rotundi C. B. Clarke in J. D. Hooker, Fl. Brit. India 6: 614. 1893.

球块茎莎草组 qiu kuai jing suo cao zu

                Herbs, perennial, with long a stolon and tuber. Culms basally leaved. Bracts long; basal bracts usually longer than inflorescence. Anthela decompound, compound, or simple. Spikes broadly ovate to obdeltoid in outline, with slightly densely or laxly arranged spikelets. Spikelets linear-lanceolate to linear, ± level spreading after anthesis; rachilla wings lanceolate to oblong, persistent; scales slightly densely imbricate, keel usually obscure, margin not involute. Stamens 3; anthers linear; connective apically prominent. Style long; stigmas 3. Achene obovoid-oblong.

                Five species in China.

7. Cyperus linearispiculatus L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 230. 1961.

线状穗莎草 xian zhuang sui suo cao

                Herbs, perennial. Stolon ± short, with fibrous roots. Culms laxly tufted, 12--15 cm tall, thin, obtusely trigonous, base swollen into a tuber, leaved at basal part. Leaves less than to longer than culm; leaf blade 2--4 mm wide, usually plicate. Bracts 3--5, leafy, longer than inflorescence, suberect. Anthela simple; rays 4--7, erect. Spikes oblong in outline, 2--4 cm X 3--4 mm, with several to 10 or more spikelets. Spikelets laxly arranged, linear, 5--12 X ca. 1 mm, erect, 8--22-flowered; rachilla wings lanceolate; scales pale to brownish yellow but middle brown striate, densely imbricate, ovate, 1.5--2 mm, membranous, not keeled, veins 5--7, apex obtuse to retuse. Stamens 3; anthers ellipsoid; connective slightly prominent. Style medium length; stigmas 3, longer than style. Achene brown when mature, oblong, ca. 2/5 as long as scale, trigonous. Fl. and fr. Apr--May.

                * Wet places by stream; elevation unknown. Yunnan [Xishuangbanna Zhou].

8. Cyperus stoloniferus Retzius, Observ. Bot. 4: 10. 1786.

粗根茎莎草 cu gen jing suo cao

                Rhizome long, ± thick, ± lignous, base of shoot with ellipsoid to ovoid tubers. Culms solitary, 8--20 cm tall, trigonous, smooth, basal sheaths usually disintegrating into fibers. Leaves usually shorter than culm to rarely longer; leaf blade 2--4 mm wide, usually folded, rarely flat. Bracts 2 or 3, leafy, basalmost 2 longer than inflorescence. Anthela simple; rays 3 or 4 rays, 0.5--2 cm, each with 3--8 congested spikelets. Spikelets oblong-lanceolate to lanceolate, 6--12 X 2--3 mm, slightly thickened, 10--18-flowered; rachilla narrowly winged; scales yellow to brownish yellow on both surfaces variegated with brownish blood red but middle green, densely imbricate, broadly ovate, ca. 3 mm, papery, veins 5--7, keel obtuse, margin broadly white hyaline, apex acute to subobtuse. Stamens 3; anthers linear; connective prominent up apex. Style medium length; stigmas 3. Achene dark brown when mature, ellipsoid to subobovoid, ca. 2/3 as long as scale, trigonous. Fl. and fr. Jul.

                Swamps, open grasslands, moist places along seashore; near sea level. Fujian, Hainan, Taiwan [Cambodia, India, Indonesia, Laos, Malaysia, Myanmar, New Guinea, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; N Australia, Indian Ocean Islands, Madagascar].

9. Cyperus rotundus Linnaeus, Sp. Pl. 1: 45. 1753.

香附子 xiang fu zi

Cyperus rotundus var. quimoyensis L. K. Dai.

                Perennials. Stolon slender, with ellipsoidal tubers. Culms solitary, rarely 2 laxly tufted, 15--90 cm tall, slightly slender, triquetrous, smooth, base swollen into a tuber, leaved at basal part. Leaves equaling or shorter than culm; sheath brown, usually disintegrating into fibers; leaf blade 2--5 mm wide, flattish. Bracts 2 or 3(or 5), longer to sometimes shorter than inflorescence. Anthela simple or compound; rays (2 or)3--10, mostly to 12 cm, unequal in length, spreading. Spikes obdeltoid in outline, with 3--10 slightly laxly arranged spikelets. Spikelets linear, 1--3 cm X 1.5--2 mm, obliquely spreading, 8--28-flowered; rachilla wings white, slightly broad, hyaline; scales blood red to purplish brown on both surfaces but middle green, subdensely imbricate, ovate to oblong-ovate, ca. 3 mm, veins 5--7, apex acute to obtuse and muticous. Stamens 3; anthers linear; connective prominent up apex. Style long; stigmas 3, longer than style, exerted from scale. Achene obovoid-oblong, 1/3--2/5 as long as scale, trigonous, puncticulate. Fl. and fr. May--Nov.

                Grasslands, wet or dry areas on mountain slopes, stream margins, among herbs at along trails, sandbanks, ditch margins, water margins in valley, paddy field margins; near sea level to 2100 m. Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hainan, Hebei, Henan, Hubei, Jiangsu, Jiangxi, S Liaoning, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Yunnan, Zhejiang [temperate, subtropics, and tropics worldwide].

                The tubers are a Chinese medicine.

10. Cyperus tuberosus Rottboell, Descr. Pl. Rar. 18. 1772.

假香附子 jia xiang fu zi

Cyperus rotundus Linnaeus subsp. tuberosus (Rottboell) Kükenthal.

                Perennials. Rhizome stoloniferous. Stolon long and creeping, terminated by a tuber. Culms solitary, rarely few laxly tufted, 20--55 cm tall, slender, triquetrous, smooth, base with several leaves. Leaves shorter than culm; sheath reddish brown, eventually disintegrating into fibers; leaf blade 3--6 mm wide, base flat or slightly folded. Bracts 2 or 3, leaflike, equaling or shorter than inflorescence. Anthela simple, rarely compound; rays 2--6, to 8 cm, unequal in length. Spikes obdeltoid in outline, with 2--11 laxly arranged spikelets. Spikelets linear, 0.8--2 cm X 1.5--2 mm, obliquely spreading, 8--20-flowered; rachilla white, broad, hyaline; scales brownish yellow to straw-colored on both surfaces but keel green, broadly ovate to elliptic, ca. 3 mm, membranous, veins 7 and conspicuous, margin white hyaline, apex rounded. Stamens 3; anthers linear; connective slightly prominent up apex. Style medium length; stigmas 3. Achene oblong-obovoid, ca. 1/2 as long as scale, trigonous, puncticulate. Fl. and fr. Jun--Jul.

                Open grasslands, along trails, sandy shores, gardens; below 1700 m. Sichuan, Taiwan, Yunnan [India, Japan (Ryukyu Islands), Malaysia; Africa, N Australia].

11. Cyperus tenuifolius L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 231. 1961. NOTE THAT THIS IS A LATER HOMONYM. IF RECOGNIZED, A SUBSTUTUTE NAME MUST BE USED.

疏鳞莎草 shu lin suo cao

                Rhizome repent. Culms solitary, 40--50 cm tall, acutely triquetrous, smooth, with 1 or 2 leaves, basalmost part ± swollen. Leaves much shorter than culm; sheath brown, equaling or longer than leaf blade; leaf blade 1--1.5 mm wide. Bracts 2 or 3, subulate, usually shorter than in florescence, erect. Anthela simple, lax; rays 3 or 4, mostly to 8 cm, slender, smooth. Spikes obdeltoid in outline, with 2--6 spikelets. Spikelets linear, 1--2.5 cm X ca. 2 mm, 12--26-flowered; rachilla wings white, linear, hyaline; scales reddish brown, very lax, eventually extended, oblong-ovate, ca. 2.5 mm, papery, not keeled, veins 5--7 with middle 3 green and conspicuous, apex obtuse to rounded and muticous. Stamens 3; anthers linear, ca. 1 mm; connective ± long prominent up apex. Style ± long to medium long; stigmas 3, ± slender. Achene straw-colored, narrowly obovoid, ca. 2/3 as long as scale, trigonous, surface with tetragonal to hexagonal reticulate striae. Fl. and fr. Oct--Nov.

                * Ditch margins; 700--800 m. Yunnan (Mengla Xian, Zhenxiong Xian).

5. Cyperus subgen. Cyperus sect. Cyperus

莎草组 suo cao zu

                Perennials. Stolons slender, with fibrous roots, apex swollen into a tuber. Culms tall, rigid, foliose. Bracts longer than inflorescence. Anthela simple or compound. Spikes ovate in outline, with laxly arranged spikelets. Spikelets linear to oblong, subcompressed, divergent after anthesis; rachilla wings broad, persistent; scales sublaxly imbricate, not keeled, conspicuously multi-veined. Stamens 3; anthers linear; connective apically prominent into a short ovoid appendage. Style long; stigmas 3. Achene obovoid-oblong, ca. 1/2 as long as scale.

                One species cultivated in China.

12. Cyperus esculentus Linnaeus sativus Boeckeler, Linnaea 30: 290. 1870.

油莎草 you suo cao

                Perennials. Stolons several, with fibrous roots, apex swollen into a tuber; tubers ellipsoid to globose, 10--18 X 5--8 mm, conspicuously nodose, surface gray tomentose when old. Culms solitary, 10--40 cm tall, triquetrous, smooth, with several leaves at basal part. Leaves ± congested, longer to shorter than culm; sheath reddish brown; leaf blade 3--6 mm wide, margin flat or revolute. Bracts 3--6, basalmost 2 longer than inflorescence. Anthela simple or compound; rays 5--10, to 12 cm, base sometimes ramose. Spikes ovate in outline, with 5--14 laxly arranged spikelets. Spikelets distichous, linear to oblong, 1--1.5 cm X 1.6--1.8(--2) mm, subcompressed, divaricate after anthesis, 10--20-flowered; rachilla broadly winged; scales yellowish to golden or reddish, ± laxly imbricate, extended at maturity, ovate to ovate-elliptic, veins 7, margin apically white hyaline, apex truncate and mucronate. Stamens 3; anthers linear; connective prominent up apex into small ovoid appendage. Style long; stigmas 3, ± long. Achene brownish gray, ellipsoid, ca. 1/2 as long as scale, trigonous, nitid, densely puncticulate.

                Cultivated in at least Guangxi, Heilongjiang, Liaoning, Xinjiang, and Yunnan [Mediterranean region].

Cyperus esculentus var. esculentus occurs in the Mediterranean region and differs by having globose to ovoid tubers, anthela rays to 4 cm, and ellipsoid achenes. Cyperus esculentus var. sativus was introduced to China before the 1970s and is now grown as an oil-plant. The oil is used as an edible or industrial oil. The tubers could be used as a starch source. This herb grows and reproduces quickly and is good for soil conservation.

6. Cyperus subgen. Cyperus sect. Subquadrangulares Kükenthal in Engler, Pflanyenr IV. 20(Heft. 101): 127. 1935.

近四稜穗莎草组 jin si leng sui suo cao zu

                Rhizome short, ligneous, with slender stolons, rarely with fibrous roots. Culms slender, trigonous, basally several foliate, base ± swollen. Bracts leaf-shaped, basal few longer than inflorescence. Anthela simple or compound; rays thin, unequal in length. Spikes broadly ovate in outline, with several spikelets. Spikelets laxly arranged, linear to linear-lanceolate, subquadrangular, usually obliquely spreading after anthesis; rachilla flexuose, wings oblong to lanceolate-elliptic and deciduous; scales slightly lax, slightly appressed, membranous, not keeled, veins many. Stamens 3; anthers oblong to linear; connective not prominent to slightly prominent. Style long; stigmas 3. Achene ellipsoid to oblong, 1/3--1/2 as long as scale, trigonous.

                One species in China.

13. Cyperus tenuiculmis Boeckeler, Linnaea 30: 286. 1870.

四稜穗莎草 si leng sui suo cao

                Rhizome short, ligneous. Culms laxly tufted, 40--75 cm, slender, triquetrous, smooth, basally with several leaves, base slightly swollen. Leaves shorter than culm; leaf blade 2--6 mm wide, margin revolute; sheath ± long, brown. Bracts (2 or)3, leaf-shaped, basalmost 1 longer than inflorescence. Anthela simple, rarely compound; rays 3--7 rays, 1--10 cm. Spikes ovate in outline, with 3--14 spikelets. Spikelets laxly arranged, obliquely spreading, nearly level spreading after anthesis, linear-lanceolate to linear, 1--2 cm X 1.5--2 mm, subquadrangular, 6--14-flowered; rachilla flexuose, winged, wings blackish brown, early deciduous; scales yellow to yellowish brown on both surfaces, slightly lax, elliptic, apex obtuse, ca. 4 mm, membranous, keel green, veins 7--9. Stamens 3; anthers linear; connective slightly prominent. Style long; stigmas 3. Achene ellipsoid to obovoid, trigonous, concave on 3 sides, ca. 1/2 as long as scale, black, densely puncticulate, Fl. and fr. May--Nov.

                Mountain slopes, open grasslands, streamside, wet place under sparse forests, fields; 200--1600 m. Fujian, Guangdong, Guangxi, Hainan, Sichuan, Taiwan, Yunnan, Zhejiang [Bhutan, Cambodia, India, Indonesia, S Japan, Laos, Malaysia, Myanmar, Nepal, New Guinea, Philippines, Sri Lanka, Thailand, Vietnam; tropical Africa and Australia, Pacific Islands].

                This species was misidentified as Cyperus zollingeri Steudel in Fl. Reipubl. Popularis Sin. 11: 137. 1961.

7. Cyperus subgen. Cyperus sect. Distantes C. B. Clarke, Bull. Misc. Inform. Kew, Addit. Ser. 8: 99. 1908.

疏穗莎草组 shu sui suo cao zu

                Herbs, perennial. Rhizome short, ligneous, surculose, usually without stolons, rarely stoloniferous. Culms tall, stout, basally foliate, base usually swollen or rarely not swollen. Bracts leaf-shaped, basal ones longer than inflorescence. Anthela compound or decompound, with many rays. Spikes penicillate in outline, with several to many spikelets. Spikelets linear to linear-oblong, subcompressed, usually suberect, rarely level spreading; rachilla flexuose, wings early deciduous; scales lax, elliptic to oblong-elliptic, membranous, slightly keeled, veins usually 5--9, apex obtuse and rarely mucronate. Stamens 3. Style long to medium, rarely short; stigmas 3. Achene oblong to obovoid-oblong, 1/3--1/2 as long as scale, trigonous.

                Four species in China.

14. Cyperus distans Linnaeus f., Suppl. Sp. Pl. 103. 1781.

疏穗莎草 shu sui suo cao

                Rhizome short, surculose. Culms 35--110 m tall, slightly stout, compressed triquetrous, smooth, base slightly swollen. Leaves shorter than or equaling culm; sheath brown, long; leaf blade 4--6 mm wide, margin flat or slightly folded and scabrid. Bracts 4--6, leaf-shaped, basal 2 or 3 longer than inflorescence, remaining ones shorter than inflorescence. Anthela compound or decompound; rays 6--10, to 15 cm, each with 3--5 raylets; raylets to 7 cm, ± thin. Spikes broadly ovate in outline, with 8--18 spikelets. Spikelets distichous, laxly arranged linear, subterete, 0.8--4 cm X less than 1 mm, obliquely to level spreading,, 6--32-flowered; rachilla thin, flexuose, wings white, hyaline and early deciduous; scales dark blood red on both surfaces, lax, elliptic, ca. 2 mm, membranous, margin apically white hyaline, keel green, veins 3--5, apex rounded. Stamens 3; anthers linear; connective prominent above anthers. Style short; stigmas 3. Achene blackish brown, oblong, ca. 2/3 as long as scale, trigonous, surface slightly prominently punctate. Fl. and fr. Jul--Aug.

                Forests, swamps, grasslands, slightly dry or wet places on slopes, river margins, along trails; below 100 to 1800 m. Guangdong, Guangxi, Hainan, Taiwan Yunnan [Bhutan, Cambodia, India, Laos, Myanmar, Nepal, Philippines, Sri Lanka, Thailand Vietnam; tropical Africa, America, Australia, and Oceanic Islands].

15. Cyperus nutans Vahl, Enum. Pl. 2: 363. 1805.

垂穗莎草 chui sui suo cao

                Rhizome short, ligneous, surculose. Culms scattered, 75--110 cm tall, stout, compressed trigonous, smooth, with leaves at basal part. Leaves shorter than culm; leaf blade 6--12 mm wide, flat, margin scabrous. Bracts 4--8, leaf-shaped, basal 3 or 4 usually longer than inflorescence, to 1.2 cm wide, abaxially serrulate apically on two lateral veins, margin scabrous. Anthela compound; rays 8--10, to 16 cm, each with 4--10 raylets. Spikes cylindric, 2--5 cm X 4--7 mm, with laxly arranged spikelets. Spikelets linear to linear-lanceolate, 5--11 X ca. 1.5 mm, suberect, 6--10-flowered; rachilla flexuose, wings white and hyaline; scales yellowish on both surfaces and rust brown striate, lax, elliptic, ca. 2 mm, spreading after anthesis, membranous, keel reddish brown, veins 7--9, apex mucronate. Stamens 3; anthers linear-oblong; connective prominent above anthers. Style very short; stigmas 3, slender, exerted. Achene dark brown when mature, oblong to obovoid-oblong, ca. 2/3 as long as scale, trigonous, surface densely and slightly prominently punctate. Fl. and fr. May--Oct.

                Sparse forests, grasslands on mountain slope, water margin in valleys, wet places, river margins, fields; below 100 to 1600 m. Guangdong, Guangxi, Guizhou, Hainan, Hunan, Sichuan, Taiwan, Yunnan [Bhutan, India, Indonesia, Malaysia, Nepal, New Guinea, Sri Lanka, Thailand, Vietnam; Africa, Australia].

16. Cyperus eleusinoides Kunth, Enum. Pl. 2: 39. 1837.

穇穗莎草 can sui suo cao

Cyperus nutans Vahl var. eleusinoides (Kunth) R. W. Haines.

                Rhizome short, surculose. Culms stout, to 1 m tall, trigonous, smooth, base swollen into a tuber shape, with leaves at basal part. Leaves shorter than culm; leaf blade 6--12 mm wide, flat, margin scabrous; sheath long, brown. Bracts 5 or 6, basal 2 or 3 longer than inflorescence. Anthela compound or decompound; rays 6--12, to 18 cm, each with 3--6 raylets; raylets mostly to 4 cm, unequal in length. Spikes oblong to cylindric, 1--3 cm X 4--10 mm, with very many spikelets. Spikelets polystichous, densely arranged, linear-oblong, 4--8 X ca. 2 mm, 6--12-flowered; rachilla winged, wings white hyaline, early deciduous; scales pale and brown striate or brown, lax, ovate-elliptic, apex mucronate, ca. 2 mm, membranous, apical margin white hyaline, veins 5--7, keel green. Stamens 3; anthers linear; connective prominent above anther. Style short; stigmas 3, ± long. Achene obovoid, trigonous, ca. 2/3 as long as scale, dark brown, surface densely and slightly prominently punctate. Fl. and fr. Aug--Dec.

                Forests, mountain slopes, sunny water margins, wet places in valleys; 200--2500 m. Fujian, Guangdong, Guangxi, Yunnan [Cambodia, India, Japan (Ryukyu Islands), Laos, Myanmar, Nepal, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; tropical Africa and Australia].

17. Cyperus glomeratus Linnaeus, Cent. Pl. II. 5. 1756.

头状穗莎草 tou zhuang sui suo cao

                Herbs, annual, with fibrous roots. Culms scattered, 30--60(--90) cm tall, stout, obtusely trigonous, smooth, basally with leaves, base slightly swollen. Leaves few, shorter to slightly longer than culm; sheath reddish brown, long; leaf blade 4--8 mm wide, margin smooth. Bracts 3 or 4, leaf-shaped, longer than inflorescence. Anthela compound; rays 3--8, mostly to 12 cm, unequal in length. Spikes subglobose, ellipsoid, or oblong in outline, 1--3 X 0.6--1.7 cm, not peduncled, with very many spikelets. Spikelets polystichous, very densely arranged, linear-lanceolate to linear, 5--10 X 1.5--2 mm, slightly compressed, 8--16-flowered; rachilla wings white, narrow, hyaline; scales reddish brown, lax, suboblong to oblong-lanceolate, slightly spreading, ca. 2 mm, not keeled, veins very obscure, margin involute, apex obtuse. Stamens 3; anthers short, oblong; connective prominent above anther. Style slightly long; stigmas 3, ± short. Achene dark gray, narrowly oblong, ca. 1/2 as long as scale, trigonous, conspicuously reticulately striate. Fl. and fr. Jun--Oct.

                Wet grassland at along trails, sandy soil at water margins, river margins, lake banks, rice paddies; 100--1300 m. Anhui, Gansu, Hebei, Heilongjiang, Henan, Hubei, Jiangsu, Jilin, Liaoning, Nei Mongol, Shaanxi, Shandong, Shanxi, Zhejiang [Japan, Kashmir, Kazakhstan, Korea, Russia, Uzbekistan; SW Asia, C and S Europe].

8. Cyperus subgen. Cyperus sect. Proceri Kunth, Enum. Pl. 2: 72. 1837.

毛轴莎草组 mao zhou suo cao

                Herbs, perennial, with slender stolons. Culms tall, ± stout, base with long leaves to rarely long sheathed and without blade or with very short blade. Bracts leaf-shaped, basal ones longer than inflorescence. Anthela compound, decompound, or rarely simple. Spikes with several to many spikelets; rachis usually hispid, rarely glabrous. Spikelets laxly to densely arranged, linear to oblong, subturgid; rachilla wings white, narrow, hyaline; scales ovate to elliptic, not keeled, margin involute, apex obtuse-rounded and usually muticous or rarely mucronate. Stamens 3; anthers linear; connective slightly prominent above anther. Style short; stigmas 3. Achene broadly ellipsoid to obovoid, trigonous, base usually with a short and slightly broad stipe.

                Four species in China.

18. Cyperus malaccensis Lamarck, Tabl. Encycl. 1: 146. 1791.

茳芏 jiang du

                Perennials. Rhizome long, ligneous, rarely with thin stolons. Culms 50--150 cm tall, 4--6 mm thick, acutely triquetrous, smooth, with long, base brown and with a bladeless sheath, apical 1 or 2 sheaths with a blade. Leaf blade absent or to 3 cm X 4--8 mm, flat. Bracts 3 or 4, leaf-shaped, to 20 cm, longer to shorter than inflorescence. Anthela simple or compound; rays 6--10, mostly to 9 cm. Spikes broadly ovoid, with 5--10 spikelets; rachis strict, glabrous. Spikelets laxly arranged, linear, 0.8--2.5(--3) cm X ca. 1.5 mm, spreading, slightly turgid, 10--42-flowered; rachilla wings white, narrow, hyaline; scales reddish brown but margin yellowish to straw-colored, lax, oblong to elliptic, 2--2.5 mm, papery, veins 7--9 but inconspicuous, margin involute at maturity, apex obtuse to rounded. Stamens 3; anthers linear; connective prominent above anther. Style short; stigmas 3, slender. Achene blackish brown when mature, narrowly oblong, almost as long as scale, trigonous. Fl. and fr. Jun--Nov.

                River margins, ditch margins, water margins, shallow water, ocean beaches, salt-marsh margins, fields (usually cultivated); below 100 to 700 m. Fujian, Guangdong, Guangxi, Hainan, Jiangsu, Jiangxi, Sichuan, Taiwan, Zhejiang [India, Indonesia, Japan, Malaysia, Myanmar, Nepal, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; SW Asia, N Australia, Pacific Islands].

                Culms are used for making mats.

1a. Apicalmost leaf with an elongated blade; basal leafy bracts longer than inflorescence, spreading; scales incurved  18a. subsp. malaccensis

1b. Leaves short-bladed to very short-bladed, sometimes basalmost sheath bladeless; leafy bracts shorter than inflorescence; scales not incurved ...........................................................................................  18b. subsp. monophyllus

18a. Cyperus malaccensis subsp. malaccensis

茳芏 jiang du

                Apicalmost leaf with an elongated blade. Basal leafy bracts longer than inflorescence, spreading. Scales slightly incurved. Fl. and fr. Jun--Oct.

                River margins, ditch margins. Hainan, Taiwan (usually cultivated) [India, Indonesia, Japan, Malaysia, Myanmar, Nepal, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; SW Asia, N Australia, Pacific Islands].

18b. Cyperus malaccensis subsp. monophyllus (Vahl) T. Koyama, Fl. Taiwan 5: 266. 1978.

短叶茳芏 duan ye jiang du

Cyperus monophyllus Vahl, Enum. Pl. 2: 352. 1805; C. malaccensis Lamarck var. brevifolius Boeckeler.

                Leaves short-bladed to very short-bladed, sometimes basalmost sheath bladeless. Leafy bracts shorter than inflorescence. Scales not incurved. Fl. and fr. Jun--Nov.

                Ocean beaches, river margins, shallow water, fields (usually cultivated), forest margins, salt-marsh margins. Fujian, Guangdong, Guangxi, Hainan, Jiangsu, Jiangxi, Sichuan, Taiwan, Zhejiang [Indonesia, Japan (Ryukyu Islands)].

                Culms are used for making mats and caps.

19. Cyperus pilosus Vahl, Enum. Pl. 2: 354. 1805.

毛轴莎草 mao zhou suo cao

                Perennials. Rhizome with slender stolons. Culms scattered, 25--85 cm tall, stout, acutely triquetrous, smooth or scabrid on angles of apical part. Leaves shorter than culm; sheath brownish, short; leaf blade 6--8 mm wide, flat, margin serrulate scabrid. Bracts 3--5, basal 2 or 3 longer than inflorescence, margin serrulate scabrid. Anthela compound or decompound; rays 3--10, mostly to 14 cm, unequal in length, each with 3--7 raylets broadly triangular in outline. Spikes ovate to oblong in outline, 2--3 X 1--2 cm, with 10--20 or more spikelets; rachis densely yellow hispid, nearly without a peduncle. Spikelets distichous, laxly arranged, linear-lanceolate to linear, 2.5--14 X 1--2.5 mm, slightly turgid, level spreading, 4--26-flowered; rachilla wings white, narrow, hyaline; scales pale, brown, reddish brown, or dark purple on both surfaces but middle green, slightly lax, broadly ovate, ca. 2 mm, thinly papery, keel inconspicuous, veins 5--7, margin white hyaline, apex mucronate or muticous. Stamens 3; anthers linear-oblong; connective prominent above anther. Style short; stigmas 3, slightly long. Achene nearly black when mature, broadly ellipsoid to obovoid, 1/2--3/5 as long as scale, trigonous, apex mucronate. Fl. and fr. Aug--Nov.

                Sparse forests, forest margins, grassland on slopes, marshes, meadows, river margins, wet places, rice paddies, water margins, along trails, parks; below 100 to 2100 m. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Jiangsu, Jiangxi, Sichuan, Taiwan, SE Xizang, Yunnan, Zhejiang [Bhutan, India, Indonesia, Japan, Malaysia, Myanmar, Nepal, Philippines, Thailand, Vietnam; W Africa, Oceanic Islands].

1a. Spikelets 5--14 mm, 8--26-flowered.

2a. Scales brown to reddish brown, broadly ovate, apex mucronate or muticous .....................................  19a. var. pilosus

2b. Scales dark purple, rotund, apex mucronate ..................................................................................  19b. var. purpurascens

1b. Spikelets 2.5--6 mm, 4--8-flowered.

3a. Spikelets 2.5--3 mm, 4--6-flowered; scale surfaces pale, apex sometimes mucronate .......................  19c. var. obliquus

3b. Spikelets 3--6 mm, 6--8-flowered; scale surfaces reddish brown to dark brown, apex muticous ....................................

.........................................................................................................................................................................  19d. var. pauciflorus

19a. Cyperus pilosus Vahl var. pilosus

毛轴莎草 mao zhou suo cao

                Spikelets 5--14 mm, 8--26-flowered; scales brown to reddish brown, broadly ovate, apex mucronate or muticous. Fl. and fr. Aug--Nov.

                Sparse forests, forest margins, grassland on slopes, marshes, meadows, river margins, wet places, rice paddies, water margins, along trails; below 100 to 1400 m. Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Jiangsu, Jiangxi, Sichuan, Taiwan, Xizang, Yunnan, Zhejiang [Bhutan, India, Indonesia, Japan, Malaysia, Myanmar, Nepal, Thailand, Vietnam; Oceanic Islands].

19b. Cyperus pilosus Vahl var. purpurascens L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 231. 1961.

紫穗毛轴莎草 zi sui mao zhou suo cao

                Spikelets 5--14 mm, 8--26-flowered; scales dark purple, rotund, apex mucronate. Fr. Oct.

                * Grassland on slope; ca. 2100 m. Sichuan, Yunnan.

19c. Cyperus pilosus Vahl var. obliquus (Nees) C. B. Clarke, J. Linn. Soc., Bot. 21: 151. 1884.

白花毛轴莎草 bai hua mao zhou suo cao

Cyperus obliquus Nees in Wight, Contr. Bot. India 86. 1834.

                Spikelets 2.5--3 mm, 4--6-flowered; scales pale on both surfaces, apex mucronate or muticous. Fl. and fr. Jun--Sep.

                Sparse forests in valleys, grasslands, along trails, river margins, wet places, rice paddies, parks; 100--500 m. Anhui, Fujian, Guangdong, Jiangxi, Sichuan, Zhejiang [Bhutan, India, Indonesia, Malaysia, Nepal, Philippines].

19d. Cyperus pilosus var. pauciflorus L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 231. 1961.

少花毛轴莎草 shao hua mao zhou suo cao

                Spikelets 3--6 mm, 6--8-flowered; scales reddish brown to dark brown on both surfaces, margin broadly white hyaline, apex muticous. Fl. and fr. Jun--Sep.

                * Mountain slopes, along trails, water margins in valley, river margins, swamps, fields; 400--1800 m. Guangdong, Jiangxi, Sichuan, Taiwan Yunnan, Zhejiang.

20. Cyperus procerus Rottboell, Descr. Icon. Rar. Pl. 29. 1773.

拟毛轴莎草 ni mao zhou suo cao

                Perennials. Rhizome with long stolons. Culms 45--85 cm tall, stout, compressed triquetrous. Leaves basal, equaling or slightly longer than culm; sheath reddish brown; leaf blade 5--10 mm wide, flattish. Bracts 3, leaf-shaped, basalmost 1 or 2 longer than inflorescence. Anthela simple or compound; rays 3--7, mostly to 15 cm, unequal in length, obliquely spreading, smooth. Spikes 1--5, broadly ovoid, with 4--16 spikelets; rachis laxly yellowish brown hispidulous or glabrous. Spikelets laxly arranged, linear-lanceolate to lanceolate, 10--25 X ca. 3 mm, slightly turgid, obliquely to level spreading, 14--36-flowered; rachilla wings white, narrow, hyaline; scales yellowish brown and reddish brown punctate but middle greenish, slightly densely imbricate, broadly ovate, ca. 3 mm, membranous, keeled, veins 7--9, margin white hyaline and undulate, apex obtuse. Stamens 3; anthers linear-oblong; connective slightly prominent above anther. Style short; stigmas 3. Achene brown, obovoid, ca. 1/2 as long as scale, trigonous, surface densely puncticulate. Fl. and fr. Jun--Oct.

                Fields, water margins, wet places; low elevations. Hainan, Taiwan [Cambodia, India, Indonesia, Laos, Malaysia, Philippines, Sri Lanka, Thailand, Vietnam; N Australia, Madagascar].

21. Cyperus babakan Steudel, Syn. Pl. Glum. 2: 6. 1855.

刺鳞莎草 ci lin suo cao

Cyperus babakensis Steudel ex Miquel.

                Perennials. Rhizome stoloniferous. Culms 60--80 cm tall, slightly stout, compressed triquetrous, smooth. Leaves basal, slightly shorter or nearly equaling culm; sheath brown and purplish red striate, basalmost one bladeless; leaf blade ca. 8 mm wide, with short and transverse septate-nodes, midvein and margin scabrous, basally conduplicate, apically flat. Bracts 3 or 4, leaf-shaped, much longer than inflorescence. Anthela simple; rays 3--5, mostly to 9 cm, each with a spike. Spikes ovoid to ellipsoid, ca. 2.5 X 1.8 cm, with several to many spikelets; rachis slightly densely yellowish brown hispidulous. Spikelets slightly densely arranged, linear-lanceolate to linear-oblong, 0.8--1.2 cm X ca. 2.5 mm, subturgid, level spreading, 12--30(--40)-flowered; rachilla wings white, narrow, hyaline; scales yellowish on both surfaces with purple striae, slightly densely arranged, ovate, ca. 2.5 mm, membranous, keel green and spinose, veins 7--9, margin white hyaline, apex obtuse and mucronate. Stamens 3; anthers oblong, connective prominent above anther. Style short; stigmas 3, ± longer than style. Achene black when mature, broadly obovoid to broadly ellipsoid, ca. 1/2 as long as scale, trigonous, surface densely puncticulate. Fl. and fr. Jun--Oct.

                Wet places, rice paddies; below 100 m. Hainan [India, Indonesia, Malaysia, New Guinea, Philippines, Thailand, Vietnam].

9. Cyperus subgen. Cyperus Sect. Iriae Kunth, Enum. Pl. 2: 38. 1837.

碎米莎草组 sui mi suo cao zu

                Herbs, annual, with only fibrous roots. Culms densely tufted, base not swollen. Bracts leaf-shaped, longer than inflorescence. Anthela usually simple or compound. Spikelets many, laxly arranged, linear to oblong, suberect to obliquely spreading after anthesis; rachilla not winged or narrowly winged; scales lax, broadly ovate to broadly obovate, keeled, apex rounded and mucronate or muticous. Stamens (2 or)3. Style usually very short, rarely ± short; stigmas 3, short. Achene obovoid to obovoid-oblong, nearly as long as scale, trigonous.

                Four species in China.

22. Cyperus iria Linnaeus, Sp. Pl. 1: 45. 1753.

碎米莎草 sui mi suo cao

                Annuals, with fibrous roots only. Culms tufted, 8--80 cm tall, slender to slightly stout, compressed triquetrous, base few-leaved. Leaves much shorter than culm; sheath reddish brown to brownish purple; leaf blade 2--5 mm wide, slightly folded or flat. Bracts 3--5, leaf-shaped, basal 2 or 3 longer than inflorescence. Anthela compound, rarely simple; rays 4--9, mostly to 12 cm, each with 5--10 or more spikes. Spikes ovoid to oblong-ovoid, 1--4 cm, with 5--20 or more spikelets. Spikelets laxly arranged, lanceolate, narrowly lanceolate, or oblong, 4--10 X ca. 2 mm, compressed, obliquely spreading, , 6--22-flowered; rachilla almost wingless; scales yellow to straw-colored, lax, broadly obovate, ca. 1.5 mm, membranous, keel middle abaxially green, veins 3--5, margin apically white hyaline, apex retuse and mucronate. Stamens 3; anthers ellipsoid; connective not prominent above anther. Style very short; stigmas ± short. Achene dark brown, obovoid to subellipsoid, nearly as long as scale, trigonous, densely prominently puncticulate. Fl. and fr. Jun--Oct.

                Forest margins, under shrubs or forests, grasslands, mountain slopes by water, along trails in valley, river margins, wet place, rice paddies; below 100 to 2000 m. Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Xinjiang, SE Xizang, Yunnan, Zhejiang [Bhutan, India, Indonesia, Japan, Kazakhstan, Korea, Laos, Malaysia, Nepal, Pakistan, Russia (Far East, E Siberia), Tajikistan, Thailand, Uzbekistan, Vietnam; tropical Africa, America, SW Asia, N Australia, S Europe, Oceanic Islands].

23. Cyperus microiria Steudel, Syn. Pl. Glumac. 2: 23. 1855.

具芒碎米莎草 ju mang sui mi suo cao

Cyperus amuricus Maximowicz var. japonicus Kükenthal (1936), not Miquel (1865--1866).

                Annuals, with fibrous roots. Culms tufted, 20--60 cm tall, slightly slender, acutely triquetrous, smooth, base several-leaved. Leaves shorter than or equaling culm; sheath purplish brown; leaf blade 2.5 mm wide, flat. Bracts 3 or 4(or more), leaf-shaped, longer than inflorescence. Anthela compound or decompound; rays 5--9, mostly to 13 cm, unequal in length. Spikes ovate, broadly ovate, or subtriangular in outline, 2--4 X 1--3 cm, with many spikelets. Spikelets slightly laxly arranged, linear to linear-lanceolate, 0.6--1.5 cm X ca. 1.5 mm, obliquely spreading, 8--24-flowered; rachilla wings white, narrow, straight, hyaline; scales straw-colored to pale, lax, broadly obovate, ca. 1.5 mm, membranous, keel abaxially extended beyond apex into a mucro, veins 3--5 and green, apex rounded. Stamens 3; anthers oblong. Style very short; stigmas 3, ± short. Achene dark brown, oblong-obovoid, nearly as long as scale, trigonous, densely prominently puncticulate. Fl. and fr. Aug--Oct.

                Forests, under shrubs, grassland on mountain slopes, wet places by river margins, ditch margins, water margins, seashores, along trails, rice paddies; near sea level to 2300 m. Anhui, Fujian, Gansu, Guizhou, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Mongol, Shaanxi, Shandong, Shanxi, Sichuan, Yunnan, Zhejiang [Japan, Korea, Vietnam].

24. Cyperus amuricus Maximowicz, Prim. Fl. Amur. 296. 1859.

阿穆尔莎草 a mu er suo cao

                Annuals, with fibrous roots only. Culms tufted, 10--60 cm tall, slender, compressed triquetrous, smooth, base with several leaves. Leaves shorter than culm; leaf blade 2--5 mm wide, flat, scabrid on apical margin and smooth on other part. Bracts 3--5, leaf-shaped, basal 2 usually longer than inflorescence. Anthela simple; rays 4--10, mostly to 12 cm, each with 1 spike. Spikes broadly ovate to oblong in outline, 1--3 X 0.8--3 cm, with several to many spikelets. Spikelets laxly arranged, linear to linear-lanceolate, 0.5--1.5 cm X 1--2 mm, obliquely spreading but level spreading after anthesis, 8--20-flowered; rachilla wings white, narrow, hyaline, persistent; scales purplish red to brown on both surfaces but middle green, slightly lax, broadly obovate to subrounded, 1--1.5 mm, membranous, slightly nitid, veins 5, midvein forming a keel, apex with a slightly recurved mucro. Stamens 3; anthers ellipsoid; connective prominent above anther. Style very short; stigmas 3, ± short. Achene blackish brown, obovoid to oblong, nearly as long as scale, trigonous, densely prominently puncticulate, apex mucronate. Fl. and fr. Jul--Oct.

                Grassland on mountain slopes, seashore, wet places in ditches, river margins, along trails, fields; below 100 to 2500 m. Anhui, Fujian, Guizhou, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Xizang, Yunnan, Zhejiang [Japan, Korea, Russia (Far East)].

25. Cyperus orthostachyus Franchet & Savatier, Enum. Pl. Jap. 2: 539. 1879.

三轮草 san lun cao

                Annuals, without rhizome and with only fibrous roots. Culms slender, 8--65 cm tall, compressed triquetrous, smooth, with few leaves at basal part. Leaves shorter than or equaling culm; sheath brownish, ± long; leaf blade 3--6 mm wide, flat, margin scabrous. Bracts 3 or 4, leaf-shaped, very much longer than inflorescence or basalmost 1 or 2 longer than inflorescence, margin scabrous. Anthela simple, rarely compound; rays 5--11, mostly to 15(--20) cm, unequal in length, each with 1(--5) spike. Spikes ovate-oblong, broadly ovate, or oblong cylindric in outline, 1--3.5 X 1--3 cm, with 5--32 or many spikelets. Spikelets slightly laxly or densely arranged, lanceolate to linear, 0.3--2.5 cm X 1--2 mm, obliquely spreading or suberect, sometimes level spreading after anthesis, 6--46-flowered; rachilla wings white, narrow, hyaline; scales purplish red on both surfaces, slightly lax, broadly ovate to elliptic, ca. 1.5 mm, membranous, keel abaxially green, veins 5--7 and obscure, margin apically white hyaline, apex rounded to retuse and muticous. Stamens 3; anthers ellipsoid, short; connective prominent above anther. Style short; stigmas 3, slightly short. Achene brown, obovoid, nearly as long as scale, trigonous, surface puncticulate, apex mucronate. Fl. and fr. Jul--Oct.

                Mountain slopes, river margins, ditch margins, grasslands, along trails, wet places, rice paddies; 300--1500 m. Anhui, Fujian, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Mongol, Shandong, Sichuan, Zhejiang [Japan, Korea, Russia (Far East, E Siberia)].

1a. Basalmost 1 or 2 bracts longer than inflorescence; spikes ovate-oblong to broadly ovate in outline, with 5--32 spikelets; spikelets slightly laxly arranged, 4--25 X 1.5--2 mm, obliquely spreading but level spreading after anthesis, 10--46-flowered ............................................................................................................................................  25a. var. orthostachyus

1b. Bracts very much longer than inflorescence; spikes oblong to oblong cylindric in outline, with many spikelets; spikelets densely arranged, 3--6 X ca. 1 mm, suberect, 6--12-flowered .............................................................................

.................................................................................................................................................................  25b. var. longibracteatus

25a. Cyperus orthostachyus var. orthostachyus

三轮草 san lun cao

                Bracts basalmost 1 or 2 longer than inflorescence. Spikes ovate-oblong to broadly ovate in outline, with 5--32 spikelets. Spikelets slightly laxly arranged, obliquely spreading but level spreading after anthesis, 4--25 X 1.5--2 mm, 10--46-flowered. Fl. and fr. Jul--Oct.

                Mountain slopes, river margins, ditch margins, grassland, along trails, wet places, rice paddies; 300--1500 m. Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Shandong, Sichuan, Zhejiang [Japan, Korea, Russia (Far East, E Siberia)].

25b. Cyperus orthostachyus var. longibracteatus L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 231. 1961.

长苞三轮草 chang bao san lun cao

                Bracts very longer than inflorescence. Spikes oblong to oblong cylindric in outline, with many spikelets. Spikelets densely arranged, suberect, 3--6 X ca. 1 mm, 6--12-flowered. Fl. Aug--Sep.

                * Swamps. Heilongjiang, Liaoning.

10. Cyperus subgen. Cyperus sect. Compressi Kunth, Enum. Pl. 2: 23. 1837.

扁穗莎草组 bian sui suo cao zu

                Herbs, annual, with only fibrous roots. Culms tufted, compressed triquetrous, canaliculated on 1 side. Bracts leaf-shaped, longer than inflorescence. Anthela simple or compound; rays unequal in length. Spikes with few to several spikelets; rachis abbreviated. Spikelets nearly digitately arranged; rachilla wings very narrow, deciduous after anthesis; scales densely imbricate, usually ovate, veins 5--13, apex mucronate. Stamens 3; anthers linear; connective prominent above anther. Style short or rarely ± long; stigmas (2 or)3. Achene obovoid, trigonous.

                One species in China.

26. Cyperus compressus Linnaeus, Sp. Pl. 1: 46. 1753.

扁穗莎草 bian sui suo cao

                Annuals, with fibrous roots. Culms tufted, 5--35 cm tall, ± slender, triquetrous, smooth, base with leaves. Leaves shorter than culm or sometimes equaling culm; sheath purplish brown; leaf blade 1.5--4 mm wide, flat, sometimes slightly plicate. Bracts 3--5, leaf-shaped, longer than inflorescence. Anthela simple; rays 2--7, 0.8--5 cm, each with 1 spike. Spikes broadly ovate to nearly flabelliform in outline, with 3--10 spikelets; rachis abbreviated. Spikelets densely and nearly digitately arranged, linear-lanceolate, 1--2.5 cm X 3--4 mm, basal ones level spreading and apical ones obliquely spreading, 10--30-flowered; rachilla wings white, narrow, hyaline; scales pale to straw-colored and on both surfaces and sometimes with rust brown striae but middle green, tightly imbricate, ovate, 3--3.5 mm, thinly coriaceous, strongly folded, keeled, veins 9--13, apex acute and with a straight and slightly long mucro. Stamens 3; anthers linear; connective prominent above anther. Style long; stigmas 3, slightly short. Achene dark brown, obovoid, ca. 1/3 as long as scale, trigonous, slightly concave on 3 sides, surface puncticulate. Fl. and fr. Jul--Dec.

                Grasslands, seashore, along trails, lake margins, under forests, stony clefts, wet sandy riverbanks, open fields, rice paddy margins; near sea level to 900 m. Anhui, Fujian, Guangdong, Guizhou, Hainan, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Liaoning, Shandong, Shanxi, Sichuan, Taiwan, Zhejiang [tropical, subtropical, and warm temperate Africa, America, Asia, and Oceanic Islands].

II. Cyperus subgen. Pycnostachys C. B. Clarke in J. D. Hooker, Fl. Brit. India 6: 597. 1893.

簇穗莎草亚属 cu sui suo cao ya shu

Cyperus subgen. Eucyperus (Grisebach) C. B. Clarke pars. Pycnostachys (C. B. Clarke) Kükenthal.

                Spikelets digitately arranged or clustered at apex of ray or raylet, rachis very abbreviated.

11. Cyperus subgen. Pycnostachys sect. Vaginati Boeckeler, Linnaea 35: 565. 1868.

多苞片莎草组 duo bao pian suo cao zu

                Rhizome short. Culms densely tufted, stout. Sheaths long, bladeless. Bracts many, nearly equal in length. Anthela compound or decompound. Spikelets 3--7, digitately arranged at apex of ray or raylet, oblong, compressed; rachilla straight, wingless; scales slightly densely imbricate, veins 3--5 on abaxial middle, apex mucronate. Stamens 3; anthers linear, apex setiferous. Style short; stigmas 3. Achene ellipsoid, rounded trigonous.

                One cultivated species in China.

27. Cyperus alternifolius Linnaeus subsp. flabelliformis (Rottboell) Kükenthal in Engler, Das Pflanzenreich IV. 20(Heft 101): 193. 1935.

风车草 feng che cao

Cyperus flabelliformis Rottboell, Descr. Icon. Rar. Pl. 42. 1773.

                Perennials. Rhizome short, thick, with ± thick fibrous roots. Culms 30--150 cm tall, slightly stout, obtusely trigonous to nearly terete, base with bladeless sheaths, apically scabrid; basal sheaths yellowish brown and cataphylloid, apical sheaths pale green and mostly to 20 cm. Bracts many, leaf-shaped, ca. 2 X as long as inflorescence, nearly equal in length, 2--12 mm wide, obliquely spreading to levelly spreading. Anthela decompound; rays numerous, 3--10 cm, each with 4--10 raylets; raylets 1--1.5 cm, each with 3--9 spikelets. Spikelets clustered at apex of raylets, ellipsoid to oblong-lanceolate, 4--10 X 1.8--3 mm, flattened, radially spreading, 6--30-flowered; rachilla straight, wingless; scales pale green, densely imbricate, ovate, ca. 2 mm, membranous, rust brown punctate, veins 3--5, apex acuminate and mucronate. Stamens 3; anthers linear, apex setose. Style short; stigmas 3, ± long. Achene brown at maturity, subellipsoid, 1/4--1/3 as long as scale, trigonous.

                Cultivated as an ornament in China and sometimes escaped and naturalized [Africa, SW Asia].

12. Cyperus subgen. Pycnostachys sect. Pseudanosporum C. B. Clarke, J. Linn. Soc., Bot. 21: 117. 1884.

宽柱莎草组 kuan zhu suo cao zu

                Rhizome very short. Roots somewhat thick. Culms stout, compressed triquetrous, leaved at basal part. Leaves ± broad, flat, septate nodose. Anthela compound or decompound; rays many, with numerous spikelets. Spikelets usually 3--6, digitately arranged at apex of raylets, oblong-lanceolate, subcompressed; rachilla wingless; scales golden rust brown, densely arranged, membranous, apex mucronate. Stamens 3; anthers linear, apex setose. Style flattened, margin pilose; stigmas 3, short. Achene ellipsoid, trigonous, concave on 3 sides, angles spongy-thickened.

                One species in China.

28. Cyperus platystylis R. Brown, Prodr. Fl. Nov. Holland. 214. 1810.

宽柱莎草 kuan zhu suo cao

                Rhizome very short. Roots somewhat thick. Culm 1(--3 and tufted), 30--90 cm tall, stout, triquetrous, scabrid on apical angles, leaved at basal part. Leaves equaling culm; sheath brownish, basal ones bladeless; leaf blade 5--12 mm wide, somewhat stiff, somewhat flat plicate, margin scabrous. Bracts 5--12, longer than in florescence, basal few to 60 cm, spreading to deflexed after anthesis. Anthela compound or decompound; rays many(--17) , 2--8 cm, ± slender, each with 4--16 raylets; raylets 1--4 cm, each with 3--7 spikelets. Spikelets digitate arranged at apex of raylets, oblong-lanceolate, 5--8 X ca. 2.5 mm, oblique or level spreading, densely 15--35-flowered; rachilla straight, wingless; scales broadly ovate, 2--2.5 mm, thickly membranous, keel abaxially greenish, veins 3 but inconspicuous, apex acute to obtuse and mucronate. Stamens 3, short. Style long, flattened, margin pilose; stigmas 3. short. Achene brownish glaucous, ellipsoid to ovoid-ellipsoid, compressed trigonous, with concave sides, nitid, angles markedly spongy-thickened and pale brown.

                Ponds or lakes; elevation unknown. Taiwan [India, Indonesia, Malaysia, New Guinea, Sri Lanka, Thailand; N Australia].

13. Cyperus subgen. Pycnostachys sect. Diffusi Kunth, Enum. Pl. 2: 25. 1837.

多脉莎草组 duo mai suo cao zu

                Rhizome short, rarely stoloniferous, lignous. Culms tall, with more leaves at basal part. Bracts longer than inflorescence, unequal in length. Anthela compound or decompound; rays many; ± long, usually 2 or 3 in a prophyll. Spikelets single or 2--6 digitately arranged at apex of rays or raylets, linear-oblong to ovoid-lanceolate, slightly turgid; rachilla wingless; scales slightly laxly to densely imbricate, veins many, apex recurved mucronate. Stamens (1--)3; anthers linear, apex cristate. Style short, rarely long; stigmas 3. Achene ellipsoid, ovoid, or oblong, trigonous.

                One species in China.

29. Cyperus diffusus Vahl, Enum. Pl. 2: 321. 1805.

多脉莎草 duo mai suo cao

                Perennials. Rhizome short, lignous. Culms 25--80 cm tall, slightly thick, triquetrous, smooth, several-leaved at basal part. Leaves equaling or shorter than culm; sheath pale green and eventually reddish brown; leaf blade 0.3--2 cm wide, flat, margin scabrous. Bracts 6--12, leaflike, longer than inflorescence, 0.6--1.6 cm wide. Anthela decompound, diffuse; rays many, mostly to 1.2--1.6 cm, each with 2--8 raylets. Spikelets sessile, 1--5, sometimes more than 3 at apex of raylets or tertiary raylets, oblong to linear-oblong, 3--7(--14) X 1.5--2 mm, slightly turgid, 6--12(--22)-flowered; rachilla narrowly winged; scales reddish brown or rust brown on both surfaces but middle abaxially green or grayish green, lax, broadly ovate to orbicular-ovate, ca. 2 mm, keel prominent, veins 7--11, apex rounded and with recurved mucro. Stamens 3; anthers linear, apex with white setae. Style very short; stigmas 3. Achene dark brown, ellipsoid, ca. 3/4 as long as scale, trigonous. Fl. and fr. Jun--Sep.

                Forests in valleys, grassland on mountain slopes, wet places by rivers, along trails, paddy fields; 100--1700 m. Guangdong, Guangxi, Hainan, Taiwan, Yunnan [Bhutan, Cambodia, India, Indonesia, Laos, Malaysia, Nepal, Philippines, Vietnam; Pacific Islands].

1a. Leaves 0.3--1.2 cm wide; bracts 0.6--1.2 cm wide; spikelets solitary or 2 or 3 digitately arranged at raylets or tertiary raylets, 3--6 mm, 6--12-flowered; scales reddish brown on both surfaces, middle abaxially green  29a. var. diffusus

1b. Leaves 0.8--2 cm wide; bracts 1--1.6 cm wide; spikelets (1 or)2--5 digitately arranged at raylets or tertiary raylets, 7--14 mm, 10--22-flowered; scales rust brown on both surfaces, middle abaxially grayish green .........  29b. var. latifolius

29a. Cyperus diffusus var. diffusus

多脉莎草 duo mai suo cao

                Leaves 0.3--1.2 cm wide. Bracts 0.6--1.2 cm wide. Spikelets (1 or)2 or 3 digitately arranged at raylets or tertiary raylets, 3--6 mm, 6--12-flowered; scales reddish brown on both surfaces, middle abaxially green. Fl. and fr. Jun--Sep.

                Forests in valleys, grassland on mountain slopes, wet places by rivers, along trails, paddy fields; 100--1700 m. Guangdong, Guangxi, Hainan, Taiwan, Yunnan [Bhutan, Cambodia, India, Indonesia, Laos, Malaysia, Nepal, Philippines, Vietnam; Pacific Islands].

29b. Cyperus diffusus Vahl var. latifolius L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 232. 1961.

宽叶多脉莎草 kuan ye duo mai suo cao

                Leaves 0.8--2 cm wide, bracts 1--1.6 cm wide. Spikelets (1 or)2--5 digitately arranged at raylets or tertiary raylets, 7--14 mm, 10--22-flowered; scales rust brown on both surfaces, middle abaxially grayish green. Fl. and fr. Aug--Sep.

                * Wet places, grasslands; elevation unknown. Guangdong.

14. Cyperus subgen. Pycnostachys sect. Fusci Kunth. Enum. Pl. 2: 37. 1837.

褐穗莎草组 he sui suo cao zu

                Annuals or rarely perennials, with fibrous roots only or rarely with a rhizome. Culms with few leaves at basal part. Bracts leaflike, longer than inflorescence, unequal in length. Anthela compound or simple, sometimes nearly decompound. Spikelets fascicled at rays or raylets into capitate arrangement; rachilla wingless; scales ± laxly imbricate, membranous, both surfaces sulcate, veins usually 3, apex muticous or mucronate. Stamens 1 or 2(or 3). Style short; stigmas 3. Achene yellowish to brown, ellipsoid to ovoid, 1/2 to nearly as long as scale, trigonous.

                Five species in China.

30. Cyperus duclouxii E. G. Camus, Notul. Syst. (Paris) 1: 244. 1910.

云南莎草 yun nan suo cao

                Perennial. Rhizome and stolons ± long, lignous. Culms scattered, 15--65 cm tall, slightly stout, compressed triquetrous, smooth, base few-leaved. Leaves usually shorter than culm, sometimes apical leaves longer than culm; sheath reddish brown, basal ones short, apical ones ± long; leaf blade 5--10 mm wide, flat. Bracts 2 or 3, leaf-shaped, longer than inflorescence, mostly to 8 mm wide, margin scabrous. Anthela compound; rays 4--8, mostly to 3.5 cm, some with raylets. Spikelets 3--10, digitately arranged at apex of rays or raylets, ovoid to lanceolate, 2--6 X 1.5--2 mm, 4--16-flowered; rachilla wingless; scales dark purple on both surfaces but middle yellowish green, densely imbricate, rounded ovate to subrounded, ca. 1.5 mm, membranous, adaxially slightly keeled, veins 3, margin apically white hyaline, apex rotund and sometimes mucronate. Stamens 2; anthers oblong; connective not prominent above anther. Style ± long to medium length; stigmas 3, longer than style. Achene yellowish, oblong to ellipsoid, ca. 2/3 as long as scale, trigonous, apex mucronate. Fl. and fr. Jun--Nov.

                * Wet grassland on mountain slopes, water margins; 1800--2600 m. Guizhou, Sichuan, Yunnan.

31. Cyperus nigrofuscus L. K. Dai, Fl. Reipubl. Popularis Sin. 11: 232. 1961.

黑穗莎草 hei sui suo cao

                Annuals, with only fibrous roots. Culms tufted, 2--12 cm tall, slightly soft, compressed triquetrous, wing-shaped at angles, smooth, base with leaves. Leaves shorter to longer than culm; sheath brownish, short; leaf blade 2--4 mm wide, flat, midvein abaxially slightly wing-shaped, margin smooth or sometimes spinulate. Bracts 2--4, leaf-shaped, longer than inflorescence. Anthela simple; rays 4--7, mostly to 1.5 cm, sometimes abbreviated, each with 7--15 densely arranged spikelets. Spikelets at apex of rays, digitately arranged, linear-oblong to linear, 4--10 X ca. 1.8 mm, 12--30-flowered; rachilla strict, wingless; scales dark purple to blackish brown on both surfaces but middle yellowish green, lax, rounded ovate to subrotund, ca. 1 mm but extended after anthesis, membranous, prominently longitudinally striate, veins 3, apex rotund and mucronate. Stamens 2; anthers oblong; connective prominent above anther. Style medium length; stigmas 3. Achene at first yellowish but brownish when mature, ellipsoid to obovoid-ellipsoid, nearly as long as scale, trigonous, smooth, apex long mucronate. Fl. and fr. Sep--Oct.

                * Wet places, shallow water; ca. 1500 m. N Sichuan.

32. Cyperus fuscus Linnaeus, Sp. Pl. 1: 46. 1753.

褐穗莎草 he sui suo cao

Cyperus fuscus f. pallescens Husnet; C. fuscus f. virescens (Hoffmann) Vahl; C. virescens Hoffmann.

                Annuals, with fibrous roots. Culms tufted, 6--30 cm tall, slender, compressed triquetrous, soft, smooth, few leaved at basal part. Leaves shorter than culm, sometimes nearly equaling culm; leaf blade 2--4 mm wide, flat, sometimes folded, margin not scabrous. Bracts 2 or 3, leaf-shaped, longer than inflorescence. Anthela compound, sometimes simple; rays 3--5, most to 3 cm, apex of each ray or raylet with 5 to more than 10 densely arranged spikelets. Spikelets narrowly lanceolate to linear, 3--10 X ca. 1.5 mm, slightly compressed, 8--24-flowered; rachilla wingless; scales purplish brown, brownish, brown, or pale yellowish on both surfaces but middle yellowish green, slightly laxly imbricate, broadly ovate, ca. 1 mm, veins 3 and obscure, apex obtuse. Stamens 2; anthers ellipsoid; connective not prominent above anther. Style short; stigmas 3. Achene ellipsoid, ca. 2/3 as long as scale, trigonous, apex apiculate. Fl. and fr. Jun--Oct.

                Swamps, water margins, ditch margins, river margins, shade places in valley, along trails, wet places, rice paddies; 100--2000 m. Anhui, Gansu, Hebei, Heilongjiang, Henan, Jiangsu, Liaoning, Nei Mongol, Ningxia, Shaanxi, Shandong, Shanxi, Sichuan, Xinjiang, Yunnan [India, Kashmir, Kazakhstan, Laos, Mongolia, Pakistan, Russia, Tajikistan, Turkmenistan, Uzbekistan, Vietnam; N Africa, SW Asia, C and S Europe].

33. Cyperus nanellus T. Tang & F. T. Wang, Fl. Reipubl. Popularis Sin. 11: 232. 1961.

汾河莎草 fen he suo cao

                Annuals, without rhizome and with fibrous roots only. Culms 1--3 cm tall, 1/2 terete, usually 1 or 2 in a sheath, base with bladeless or bladed sheaths. Leaves shorter than culm; sheath brownish, short, scarious at 1 side; leaf blade ca. 2 mm wide, flat or folded, margin not scabrous. Bracts 2, leaf-shaped, shorter to slightly longer than inflorescence, adaxially ± blackish purple, base ± wide. Anthela simple and abbreviated into capitate; rays few, very abbreviated, each with a few spikelets at apex. Spikelets densely arranged at apex of ray, oblong to linear-oblong, 3--7 X 1.2--1.8 mm, 8--22-flowered; scales blackish purple but adaxially pale yellowish at middle, slightly densely imbricate, compressed rounded, ca. 1 mm, membranous, conspicuously longitudinally striate, veins 3 but obscure, margin apically white hyaline and usually involute. Stamens 2; anthers oblong, apex rotund to truncate, muticous, and mucronate. Style short; stigmas 3, longer than style. Achene yellowish, ellipsoid, as long as scale, trigonous, smooth. Fl. and fr. Oct.

                * Sand by stream margins; ca. 800 m. Shanxi.

34. Cyperus difformis Linnaeus, Cent. Pl. II. 6. 1756.

异型莎草 yi xing suo cao

                Annuals, with fibrous roots. Culms tufted, 2--65 cm tall, slightly thick or flaccid, compressed triquetrous, smooth, few-leaved at basal part. Leaves shorter than culm; sheath brown, slightly long; leaf blade 2--6 mm wide, flat or folded. Bracts 2(or 3), leaf-shaped, longer than inflorescence. Anthela simple, rarely compound; rays 3--9, mostly to 3(--5) cm, unequal in length, each with many spikelets at apex and densely arranged into a capitulum; capitulum globose, 0.5--1.5 cm in diam. Spikelets lanceolate to linear, 2--8 X ca. 1--1.2 mm, 8--28-flowered; rachilla wingless; scales darkly reddish purple to dark grayish brown on both surfaces but middle yellowish, slightly lax, compressed rounded, less than 1 mm, veins 3 and obscure, margin white hyaline, apex rotund. Stamens (1 or)2; anthers ellipsoid; connective not prominent above anther. Style very short; stigmas 3, short. Achene yellowish, obovoid-ellipsoid, nearly as long as scale, trigonous. Fl. and fr. Jul--Oct.

                Grassland at mountain slopes, shallow water, water margins, lake margins, wet places in grasslands, along trails, rice paddies; below 100 to 2000 m. Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hainan, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jilin, Liaoning, Nei Mongol, Ningxia, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Yunnan, Zhejiang [Bangladesh, Bhutan, India, Indonesia, Japan, Kashmir, Korea, Malaysia, Myanmar, Nepal, New Guinea, Pakistan, Philippines, Russia, Sri Lanka, Tajikistan, Thailand, Uzbekistan; Africa, North America, SW Asia, Australia, S Europe, Pacific Islands].

15. Cyperus subgen. Pycnostachys sect. Haspani Kunth, Enum. Pl. 2: 34. 1837.

窄穗莎草组 zhai sui suo cao zu

                Perennials or rarely annuals. Rhizome abbreviated to elongate but annuals with only fibrous roots, sometime with stolons. Culms with few leaves at basal part, sometimes sheathed; sheath long and bladeless. Anthela compound, decompound, or simple. Spikelets 3--7, digitately arranged at apex of rays or raylets, compressed; rachilla wingless; scales slightly densely to laxly imbricate, membranous, keel abaxially green, both surfaces sulcate, apex mucronate. Stamens (1--)3; anthers setiferous or not at apex. Style long; stigmas 3, slightly slender. Achene 1/4--1/3 as long as scale, surface ± tuberculate.

                Two species in China.

35. Cyperus tenuispica Steudel, Synops. Pl. Glumac. 2: 11. 1854.

窄穗莎草 zhai sui suo cao

                Annuals, with fibrous roots. Culms tufted, 3--30 cm tall, flaccid, compressed triquetrous, smooth, base clothed with a few bladeless sheaths, apical sheaths with short blade. Leaves shorter than culm, 2--3 mm wide, flat; sheath reddish brown to purplish brown, 2--6 cm. Bracts usually 2(or 3), leaf-shaped, usually basalmost 1 equaling to longer than inflorescence. Anthela compound, sometimes simple; rays 4--10, mostly to 7 cm, unequal in length, each with 2--9 raylets. Spikelets 3--12, digitately arranged at apex of raylets or rays, linear, 3--12 X ca. 1 mm, 10--40-flowered; rachilla wingless; scales dark brown on both surfaces but middle abaxially yellowish green, lax, elliptic to suboblong, 0.8--1 mm, membranous, slightly spreading after anthesis, veins inconspicuous, apex obtuse to truncate and slightly recurved muticous. Stamens 1 or 2; anthers not setose at apex. Style long; stigmas 3. Achene yellowish, obovoid, ca. 0.3 mm, surface tuberculate. Fl. and fr. Sep--Nov.

                Sparse forests, along trails, wet places, rice paddies; 300--500 m. Anhui, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Jiangxi, Sichuan, Taiwan, Zhejiang [Bhutan, India, Indonesia, S Japan, Kashmir, Korea, Laos, Malaysia, Nepal, Philippines, Sri Lanka, Tajikistan, Thailand, Vietnam; tropical Africa, Australia].

36. Cyperus haspan Linnaeus, Sp. Pl. 1: 45. 1753.

畦畔莎草 qi pan suo cao

                Perennials or annuals, with short to slightly long rhizome, when annual with fibrous roots. Culms tufted or scattered, 10--60 cm tall, slender, compressed triquetrous, smooth. Leaves short than culm, sometimes sheathed only and bladeless; sheath pale green, base purplish brown to reddish purple, 2--10 cm; leaf blade 2--3 mm wide. Bracts usually 2, leaf-shaped, shorter to rarely longer than inflorescence. Anthela compound, simple, or rarely decompound; rays 8--12, mostly to 17--30 cm, unequal in length, each with several rayl