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23. Rhynchospora Vahl, Enum. Pl. 2: 229. 1805.
刺子莞属 ci zi guan shu
Authors: Prof. Song-Yun Liang & David A. Simpson
Herbs, perennial or more rarely annual. Culms tufted, erect, 3-angled or terete. Leaves basal or cauline; sheath closed, with or without a ligule; leaf blade linear, flat or canaliculate. Involucral bracts leaflike, sheathing. Inflorescences paniculate, usually consisting of terminal and lateral anthelae, sometimes spicate or capitate. Spikelets sessile or pedunculate, narrowly ovoid, ovoid, or ellipsoid, slightly bilaterally compressed or terete. Glumes few to many, spirally imbricate or rarely distichous, 1-veined; basal 3 or 4 glumes shorter than apical ones and empty. Flowers bisexual or basal flower bisexual and apical one male or sterile. Perianth bristles 0-6(-13), antrorsely or retrorsely scabrous, rarely smooth. Stamens 2 or 3. Style slender; stigmas 2. Nutlet usually obovoid to ovoid, biconvex, with various ornamentations or more rarely smooth; persistent style base thickened, mostly conic or rarely lunate, spongy, base truncate or ± lobed.
About 350 species: cosmopolitan but particularly in tropics and subtropics of the New World; nine species in China.
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1 |
Inflorescences with 1 to several globose heads |
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(2) |
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Inflorescences paniculate, consisting of terminal and lateral open panicles |
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(4) |
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2 (1) |
Inflorescence with 2-7 spicate heads. |
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7 R. malasica |
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Inflorescence with 1 terminal head |
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(3) |
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3 (2) |
Nutlet obovoid; perianth bristles 1/3-1/2 as long as nutlet. |
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8 R. rubra |
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Nutlet linear-oblong; perianth bristles longer than nutlet and persistent style base. |
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9 R. submarginata |
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4 (1) |
Perianth bristles absent; persistent style base saddle-shaped, much depressed and much broader than high; nutlet 1.3-1.5 mm, coarsely transversely wrinkled; leaf blade setaceous. |
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6 R. gracillima |
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Perianth bristles present; persistent style base compressed conic to almost subulate; nutlet 2-4 mm; leaf blade flat or canaliculate, not setaceous |
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(5) |
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5 (4) |
Leaf blade 9-17 mm wide; nutlet 3-4 mm, deeply channeled; style hardly divided. |
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1 R. corymbosa |
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Leaf blade 0.5-4 mm wide; nutlet ca. 2 mm, not channeled; style 2-cleft |
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(6) |
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6 (5) |
Perianth bristles 9-13, retrorsely scabrous. |
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2 R. alba |
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Perianth bristles less than 6, antrorsely or retrorsely scabrous |
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(7) |
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7 (6) |
Leaf blade 0.5-1 mm wide; perianth bristles retrorsely scabrous. |
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3 R. faberi |
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Leaf blade 1.5-3 mm wide; perianth bristles antrorsely scabrous |
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(8) |
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8 (7) |
Spikelets 3-4.5 mm; perianth bristles shorter than nutlet and persistent style base. |
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4 R. rugosa |
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Spikelets 7-9 mm; perianth bristles longer than nutlet and persistent style base. |
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5 R. chinensis |
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Lower Taxa
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