Ixeris polycephala

多頭苦菜

Ixeris polycephala Cass.

名彙資訊

特徵描述

典藏標本

數位照片

分布位置

相關資訊

名彙資訊

學名發表文獻

Cass., Dictionnaire des Sciences Naturelles 24: 50. 1822. (Dict. Sci. Nat.)

台灣首次記錄發表文獻

Kitamura, Memoirs of the College of Science, Kyoto Imperial University. Series B. Biology 23: 106. 1956. (Mem. Coll. Sci. Kyoto Imp. Univ., Ser. B, Biol.)

異名

Ixeris polycephala Cass. var. dissecta (Makino) Nakai

Nakai, The Botanical magazine, Tokyo 38: 265. 1924. (Bot. Mag. Tokyo)
Lactuca matsumurae Makino

Kitamura, Acta phytotaxonomica et geobotanica eng 1: 152. 1932. (Acta Phytotax. Geobot.)
Ixeris polycephala Cass. f. dissecta (Makino) Ohwi

Kitamura, Memoirs of the College of Science, Kyoto Imperial University. Series B. Biology 23: 107. 1956. (Mem. Coll. Sci. Kyoto Imp. Univ., Ser. B, Biol.)

各語言俗名

中

野剪刀股.
日

きくばのにがな. のにがな. にがな.

參考文獻

Yang, A list of plants in Taiwan . 1982. (List Pl. Taiwan)

特徵描述

生活型

herb

形態特徵

Annual; stems 17–50 mm long, branched at base, glabrous.
Leaves glabrous; radical leaves linear-lanceolate, 7–17×0.5–1.5 cm, sessile, sagittate, margins entire, slightly mucronulate to pinnately dissected, apex acuminate to acute or obtuse, base narrowed; median cauline leaves lanceolate, 6–17×1–1.7 cm, margins entire or slightly mucronate, upper leaves few, lanceolate, base auriculate, sessile.
Heads nodding after flowering, in false umbels; peduncle slender, 6–28 mm long, bracteoles 1 or 2, 0.5 mm long. Involucre cylindric, 5–7×2.5–3.5 mm; outer bracts few, ovate, 0.5 mm long; inner bracts 8, ovate-lanceolate, margins transparent, apex corniculate or not. Florets 20–25; corolla 8–8.5×1 mm.
Achenes slightly compressed, 3.5–4×*0.7–0.5 mm, 10-angled; beak slender, 1 mm long. Pappus white, 3.5–4 mm long, persistent.
Ixeris polycephala is highly variable in leaf shape. Plants with pectinate-pinnatifid leaves were given infraspecific ranks as f. dissecta or var. dissecta.