毛梗豨莶 mao geng xi xian

Sigesbeckia orientalis Linnaeus f. glabrescens Makino, Bot. Mag. (Tokyo) 18: 100. 1904; S. formosana Kitamura; S. glabrescens var. leucoclada Nakai; S. orientalis subsp. glabrescens (Makino) H. Koyama.

Annuals. Stems 35-100 cm tall, shortly appressed pilose. Median cauline leaves with winged petiole, blade ovate-deltate, 5-13 × 3.5-11 cm, irregularly toothed, upper surface shortly appressed pubescent; upper leaves sessile, oblong; uppermost leaves linear. Capitula radiate, ca. 12 mm wide; peduncle 1-3 cm, densely shortly pubescent; phyllaries spatulate, densely glandular pilose. Ray limb 1.5-2.5 mm, 3-toothed, tube 0.5-1 mm, pilose; disk corolla ca. 1.5 mm, 3-toothed, tube ca. 0.5 mm, densely pilose. Achenes ca. 2 mm. Fl. Apr-Sep, fr. Jun-Sep. 2n = 30.

Roadsides, fields, thickets; 300-2500 m. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Liaoning, Sichuan, Taiwan, Yunnan, Zhejiang [Japan, Korea].