生活型

herb

形態特徵

• Annual herbs; stems erect, 25–30 cm long, with long internodes, short pilose, dichotomously branched.
• Median cauline leaves ovate, 5–12×2–6 cm, apex acute to obtuse, base cuneate into short winged or wingless petiole, margins short serrulate, strigose-pubescent on both surfaces, 3-nerved; upper leaves smaller, 3.5–4 cm long.
• Inflorescences globose, in leaf axils. Heads sessile or short pedunculate; involucre tubular, ca. 7×5–7 mm, bracts and outer paleae oblong, obtuse, 7 mm long, inner ones 6.5 mm long. Ray florets yellow, corolla ca. 3.5×1 mm. Disc florets yellow, 4×2 mm, oblong, wings lacerate, apex 2-awned.
• achenes compressed, oblong, 4.5×1 mm, coarsely strigose, 2-awned, 2–3.5 mm long, strigose.
• Chromosome number, 2n = 40 (Peng & Hsu, 1978).

分布

• 台灣 : widespread throughout the island.
• 世界 : Common weed of the lowland tropics.

引證標本

ILAN: Chuangwei, Peng 7019. TAOYUAN: Fuhsing, Peng 10282. HSINCHU: Nanliao, Leu 934; Chupei, Leu 1640. MIAOLI: Sanyi, Peng 6335. TAICHUNG: Takeng, Peng 9952; Taiping, Hsiao 1332. NANTOU: Lienhuachih, Lin 240. TAINAN: Nanhsi, Peng 13427. KAOHSIUNG: Shanping, Peng 11240. PENGHU: Chimei Is., Chen 742. PINGTUNG: Wutai, Lin 360. TAITUNG: Lanyu, Peng 6633. HUALIEN: Taroko, Chen 325.

參考文獻

• PENG, Ching-I & CHUNG, Kuo-Fang; LI, Hui-Lin, Flora of Taiwan, second edition 4: 1075. 1998.  (Fl. Taiwan 2nd edit.)