生活型

herb

形態特徵

• Annual or perennial without rhizome; culms densely tufted, 10-60 cm by 1-5 mm, 4-5-angular, smooth, glabrous.
• Few upper leaves bladed, lower leaves cataphylloid; blades linear, laterally compressed, 10-50 cm by 1-4 mm, acuminate, light green, grooved on inner margin; basal sheaths laterally flattened, 1-18 cm long, cauline sheaths tubular, 2-10 cm long, greenish to rusty brown; ligule absent.
• Inflorescence compounde to decompound, loose to subdense, 3-10 cm by 3-10 cm; involucre bracts 2-4, setaceous, 1/2-1/3 length of primary branches; primary branches 3-7, unequal, patent, 1-5 cm long, scabird. Spikelets many per inflorescence, solitary, ovoid-globose to globose, 1.5-5 mm by 1-2 mm, rounded, rusty-brown, densely many-flowered.
• Glumes many per spikelet, spiral, 1-1.2 mm by 0.8-1 mm, patent, margins white-hyaline, 3-nerved keel ending below apex. Stamens 1-2; anthers ca. 2/3 mm long. Style triquetrous, glabrous, slightly dilated at base; stigmas 3. Achenes bradly obovate, trigonous, 0.7-1 mm by 0.3-0.5 mm, cream-yellow, cancellated with rows of fine, transversely oblong cells, usually sparsely verruculose.

分布

• 台灣 : common in rice fields and other marshy places.
• 世界 : Pantropical.

引證標本

ILAN: Lutung, Kuoh 1712. TAIPEI: Fulung, Kuoh 4157; Wulai, Hsu 3487. TAOYUAN: Yangmei, Cheng 48. YUNLIN: Huwei, Chuang & Kao 4115. CHIAYI: Fenchihu, Feng & Kao 260. TAINAN: Sanhutan, Kuoh 4130. PINGTUNG: Hengchun, Wang 12704. TAITUNG: Lanyu Is., Sasaki s. n.

參考文獻

• KOYAMA, Tetsuo, KUOH, Chang-Sheng & LEONG, Wai-Chao, Flora of Taiwan, second edition 5: 271. 2000.  (Fl. Taiwan 2nd edit.)