生活型

herb

形態特徵

• Subdensely tufted with short rhizome. Culms 45-130 cm tall, 5-11 mm thick below, acutely triquetrous with shallowly concave sides, deep green, dull, surrounded at base with 2-4 sheaths only.
• Sheaths membranaceous to herbaceous, lower ones scale like, brown, upper ones pale, 7-25 cm long, often septate-nodose below, obliquely truncate at mucronate orifice.
• Inflorescence a pseudo-lateral hemispherical head, with (3-)5-20 spikelets; bract upright or obliquely bent, 3-10 cm long, rather gradually narrowed above to subacute apex. Spikelets oblong to lanceolate, 1-2 cm long, 4-6 mm wide, terete, contracted at base, gradually subacute at apex, brownish greenish, densely many-flowered.
• Glumes ovate to widely ovate, 3.8-5 mm long, 2.5-3 mm wide, chartaceous, pale-green and brownish tinged, usually with brown lineolae, minutely ciliolate on upper margin, contracted above to mucronate apex; keel green 3-nerved. Achenes broadly obovate, 2-2.5 mm long, 1.5-2 mm wide, compressed, trigonous, contracted to cuneate base, rounded to mucronate apex, sides maturing black-brown, somewhat shiny, inconspicuously transversely wrinkled; style ca. 4 mm long, 3-cleft. Hypogynous bristles 6, 1.5-2 times length of achene, retrorsely scabrous.

分布

• 台灣 : Shallow water at margin of marsh or river, frequently found also, in rice field.
• 世界 : Temperate and tropical Asia: Japan, China, Indochina, India, Sri Lanka and Malesia.

引證標本

TAIPEI: Peitou, Faurie 169; Chishingshan, Hsu et al. 198; Tanshiu, Faurie 807; Mururoshu, Suzuki 7326; Karasan, Suzuki 6233. ILAN: Taipingshan, Suzuki s. n. 1928; Ohwi 2395. HSINCHU: Yuenyanghu, Hsu & Kuoh 14256. TAOYUAN: Pate, Chuang 4587; Taoyuan, Suzuki s. n. 1933. NANTOU: Sun Moon Lake, Kudo & Sasaki 15270. PINGTUNG: Pingtung, Yasukawa s. n. 14 Sep 1923. TAITUNG: Hsinkan, Kawakami s. n. 8 June 1906. HUALIEN: Hualien, Ito s. n.

參考文獻

• KOYAMA, Tetsuo, KUOH, Chang-Sheng & LEONG, Wai-Chao, Flora of Taiwan, second edition 5: 300. 2000.  (Fl. Taiwan 2nd edit.)