生活型

herb

形態特徵

• Perennial suffrutescent herbs, rhizomes elongate, stoloniferous. Stems terete, 30–70 cm tall, erect, branching, nearly glabrous or sparsely pubescent upward.
• Radical leaves elliptic to oblanceolate, withered at anthesis. Cauline leaves elliptic to oblanceolate, thin chartaceous, middle leaves 3–10 cm long, 1–2.5 cm wide, apex acute, narrowed gradually to base, subsessile, coarsely dentate apically, nearly glabrous or scarcely puberulous on both surfaces, minutely ciliolate, mid veins convex and sparsely pubescent on lower surface; leaves on upper branches smaller, lanceolate, entire, 1–2 cm long.
• Heads few to many in loose corymbs, 1.5–2.5 cm across, peduncle, 3–4.5 cm long. Involucre hemispheric, 4.5–5.5 mm long, 5.5–6 mm wide, bracts green to purplish brown, 3- or 4-seriate, oblanceolate, apex triangular, acute, sparsely pubescent apically, margins submembranaceous, ciliolate, midrib evident, inner bracts gradually longer 3.5–4.5 mm long, 1.5–2 mm wide, outer bracts 3–4 mm long, 1–1.5 mm wide. Ray florets 15–20 in one row, sometimes in 2 series, ligules bluish purple, 6–10 mm long, 1.4–2.3 mm wide, tube 1.5–1.7 mm long. Disc florets yellow, 3.5 mm long, 5-lobed. Pappus inconspicuous, bristles unequal, few, reddish, 0.2–0.4 mm, sometimes lacking.
• Achenes dark brownish, obovate-oblong, compressed, 1.5–2 mm long, 0.5–1.3 mm wide, sparsely pubescent, with sparse sessile glands on upper part.
• Chromosome number, 2n = 54 (Peng & Hsu, 1978; Gu, Cathaya 1: 4. 1989).

物候

Fl. May-Oct.

分布

• 台灣 : from the seacoast to low elevation wet places.
• 世界 : Distributed widely: southeast Asia, central to southern China, South Korea, Japan, Indo-china and India.

引證標本

TAIPEI: Tanshui, Faurie 226 &1141; Sanhsia, Peng 6229. ILAN: Tali, Shimada 5472B. HSINCHU: Hengshan, Peng 12149. CHIAYI: Peikang, Peng 6004; Lutsao, Peng 10082. TAINAN: Tungshan, Peng 7092. TAITUNG: Mt. Liyushan, Peng 10628.

參考文獻

• PENG, Ching-I & CHUNG, Kuo-Fang; LI, Hui-Lin, Flora of Taiwan, second edition 4: 855. 1998.  (Fl. Taiwan 2nd edit.)