151. Zoysia Willdenow, Ges. Naturf. Freunde Berlin Neue Schriften. 3: 440. 1801.
结缕草属 jie lü cao shu
Authors: Shou-liang Chen & Sylvia M. Phillips
Osterdamia Necker ex Kuntze, nom. illeg. superfl.
Perennials, rhizomatous and/or stoloniferous, sward forming. Culms arising from nodes along stolons, often densely branched at ground level. Leaf blades conspicuously distichous, stiff, flat or involute; ligule short, ciliolate. Inflorescence a cylindrical, dense, spikelike raceme; spikelets appressed to axis, falling entire; pedicels persistent, flattened, sometimes widened upward. Spikelets laterally compressed, floret 1; lower glume usually absent; upper glume as long as spikelet, enclosing floret, laterally compressed, leathery, rounded on back, smooth, glossy, apex acute or midvein excurrent into mucro; lemma membranous, 1–3-veined, apex acute or emarginate; palea reduced or absent. Lodicules absent. Styles connate at base, stigmas apically exserted. Caryopsis ovoid. x = 9, 10.
Nine species: tropical and subtropical coasts of the Indian Ocean, W Pacific, and Australasia; several species widely introduced elsewhere as tropical lawn grasses; five species in China.
The spikelets often consist of only two scales: a leathery, glossy glume (technically the upper glume) enclosing a much thinner lemma.
The species are good sand-binding and lawn grasses.
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1 |
Spikelets usually ca. 2 mm wide; uppermost leaf sheaths inflated, enclosing base of inflorescence. |
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1 Z. macrostachya |
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Spikelets less than 1.5 mm wide; uppermost leaf sheaths not inflated |
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(2) |
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2 (1) |
Spikelets ovate, 2–2.5 times as long as wide; pedicels flexuous, usually longer than spikelet. |
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2 Z. japonica |
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Spikelets lanceolate to oblong, 3–4 times as long as wide; pedicels straight, usually shorter than spikelet |
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(3) |
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3 (2) |
Spikelets 4–8 mm. |
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3 Z. sinica |
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Spikelets 2–3 mm |
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(4) |
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4 (3) |
Leaf blades 1.5–2.5 mm wide (when flattened); inflorescence 2–4 cm; spikelets 10–30. |
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4 Z. matrella |
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Leaf blades ca. 1 mm wide, setaceous; inflorescence up to 1.5 cm; spikelets 6–12. |
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5 Z. pacifica |
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Lower Taxa