生活型

herb

形態特徵

• Large annual herbs, to 2 m tall; green, somewhat reddish; stems glabrous or more less soft pubescent.
• Leaves ovate to rhombic-ovate, 6–12 cm long, 4–7 cm wide, cuneate at base, acute to subobtuse at apex, entire, or slightly crenate-undulate, glabrous above, paler and soft pubescent on veins beneath; petioles 3–8 cm long.
• Inflorescences terminal and in upper axils, greenish, the terminal to 25 cm long, much branched with lateral spikes ca. 2–5 cm long, axis soft pubescent; flowers usually with prominent bracts, bracts membranaceous near base, long-awned, green, 2–4 mm long, perianth segments 5, oblong-lanceolate, 1.5–2 mm llong, apex obtuse or slightly mucronulate, slightly shorter than urticles; stamens 5.
• Utricles compressed, dehiscent, circumscissile. seeds black, ca. 1 mm across, strongly shining.

分布

• 世界 : Native in tropical America, naturalized weeds common in waste places, roadsides.

引證標本

HSINCHU: Chuton, Kao 10131. TAICHUNG: Taichung, Lu & Ou 5907. CHANGHUA: Chihu, Kao 10168. YUNLIN: Hsilo, Hsu 4756. PINGTUNG: Nanjenshan, Kao 10254.

參考文獻

• LIU, TANG-SHUI and KAO, MUH-TSUEN, Flora of Taiwan, second edition 2: 398. 1996.  (Fl. Taiwan 2nd edit.)