生活型

herb

形態特徵

• Perennial with short, horizontal rhizome, clothed with brownish scales; culms densely tufted, obtusely trigonous, 20-90 cm by 1-5 mm, smooth, glabrous, light green, clothed at base with 2 or 3 bladeless sheaths.
• Leaves cauline reduced to bladeless sheath, sterile shoot ones usually short-bladed; sheaths cylindrical, 2-18 cm long, obliquely truncate at orifice; balde linear when well-developed, 7-25 cm by 1.5-2 mm; ligule absent.
• Inflorescence simple to compound, 2-10 cm by 1.5-7 cm; involucre 2-3, narrowly lanceolate, margins scarious, longest 0.5-1 cm long; primary branche 2-10, unequal, 1-5 cm long. Spikelets 3-40 per inflorescence, solitary, broadly ovate to broadly elliptic, 3-8 mm by 3-4 mm wide, obtuse, terete, densely many-flowered.
• Glumes many per spikelet, spiral, ovate to ovate-elliptic, 1.8-2.7 mm by 1-1.5 mm, obtuse to mucronate, membranaceous, yellow- or rusty-brown, scarcely keeled, 3-nerved in center. Stamens 2-3; anthers c. 0.5 mm long. Style triquetrous or trifid, glabrous, dilated at base; stigmas 3, rarely 2. Achenes obovate or obovate-orbicular, 0.8-1 mm by 0.5-0.7 mm, shortly stiputate, maturing milky-yellow, obscurely cancellated with transversely oblong cells, rarely sparsely verruculose.

分布

• 台灣 : in marshy places, rice fields and wet grasslands.
• 世界 : India, Indochina, southern China, Japan, Malesia, Micronesia and Polynesia.

引證標本

TAIPEI: Nankang, Kuoh 2219. NANTOU: Sun Moon Lake, Hsu 12450.

參考文獻

• KOYAMA, Tetsuo, KUOH, Chang-Sheng & LEONG, Wai-Chao, Flora of Taiwan, second edition 5: 281. 2000.  (Fl. Taiwan 2nd edit.)