生活型

herb

形態特徵

• Perennial herbs to 40 cm long; stems usually simple, branches 4-angled, puberulous along the angles when young, later terete and glabrous.
• Leaves oblong-lanceolate, 1.5–6 cm long, 4–15 mm wide, apex acute, base obtuse to attenuate, glabrous to somewhat scabrous; petiole 1–5 mm long; stipules ca. 4 mm long, ca. 2 mm wide, with 7–9 setae.
• Flowers many in bracteolate heads, bracteoles linear; calyx lobes 4, deltate, ca. 0.8 mm long, hirtellous; corolla campanulate-ureolate, white, 4–5 mm long, tube and throat pilose inside, lobes pubescent on upper outside, elliptic-ovate, tinged pink; stamens inserted on the corolla tube, with distinct filaments, exsert; style ca. 3.5 mm long, exserted.
• Fruit obovoid, ca. 3 mm long, hispidulous.

分布

• 台灣 : in the southern part at low elevations, naturalized in cultivated fields, lawns, and in dry ditches.
• 世界 : Native to tropical America; widely naturalized in tropical Asia and Africa.

引證標本

CHIAYI: Chiayi, Peng 10087; Shuiyuanti, Tang 765. PINGTUNG: Wanluan, Chaw & Peng 260.

參考文獻

• LIU, Ho-Yih, YANG, T. Y. Aleck, LI, Sung-Po and LI, Hen-Jung, Flora of Taiwan, second edition 4: 327. 1998.  (Fl. Taiwan 2nd edit.)