Family: Cyperaceae
Eleocharis
Citation:
R. Br., Prod. Fl. Nov. Holl. 224 (1810).
Derivation: Greek helos, heleos, a marsh; chairo, I delight in.
Synonymy: Not Applicable Common name: Spikerushes.
Description:
Annual or perennial herbs, often stoloniferous, leafless; stems slender or stout, tufted or in a linear series along slender rhizomes; leaves represented by 1 or more sheaths at the base of the stems.
Spikelets solitary, terminal, erect, ebracteate, few- to many-flowered, with a bract continuing the stem; glumes imbricate all round the rhachilla; flowers bisexual; hypogynous bristles filiform or very slender, usually retrorsely barbellate, to 10 in number or absent; style 3-fid (sometimes 2-fid in other areas); stamens 1-3.
Nut crowned by the persistent enlarged base of the style.
Distribution:
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About 200 species, cosmopolitan. (S.T. Blake (1939) Proc. R.Soc. Qld 50, 12:88-132). Has been spelt Heleocharis by some early authors.
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Biology:
No text
Key to Species:
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1. Stems 4-12 mm wide, prominently transversely septate |
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E. sphacelata 8. |
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1. Stems not more than 4 mm wide, not septate. |
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2. Leaf sheaths hyaline, scarious or withered at the apex, not mucronate; hypogynous bristles much smaller than the nut or 0. |
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3. Plants not producing tubers; spikelets ovate to linear, often setting fruit; glumes 2-2.2 mm long |
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E. pusilla 7. |
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3. Plants producing tubers; spikelets lanceolate to linear, rarely maturing; glumes c. 3 mm long or more |
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E. atricha 2. |
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2. Uppermost leaf sheaths prominently thickened at the mouth; hypogynous bristles about as long as or longer than the nut. |
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4. Nut trigonous; leaf sheath oblique at the mouth, usually not mucronate; style 3-fid |
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E. gracilis 4. |
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4. Nut biconvex; leaf sheath truncate and mucronate at the top or, if oblique, then the style 2-fid. |
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5. No creeping rhizome; nut with rib-like margins (sometimes faintly so). |
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E. geniculata 3. |
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6. Leaf sheath truncate and mucronate |
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E. pallens 5. |
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5. Rhizome creeping; margins of nut not thickened. |
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7. Culms terete or nearly so |
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E. acuta 1. |
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7. Culms strongly flattened |
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E. plana 6. |
Author:
Not yet available
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