假臭草 jia chou cao

Eupatorium clematideum Grisebach, Abh. Königl. Ges. Wiss. Göttingen 24: 172. 1879, not (Wallich ex Candolle) Schultz Bipontinus (1866); E. urticifolium Linnaeus f. var. clematideum Hieronymus ex Kuntze; E. catarium Veldkamp.

Subshrubs or annual herbs, to 0.6 m tall. Stems erect or ascending, bright green, simple or poorly branched at base, leafy throughout except at base, pubescent throughout, hairs simple, eglandular. Leaves opposite, rank-smelling; petiole 3-7 mm; blade ovate, 20-35 × 12-25 mm, pubescent below, hairs long, simple, eglandular along venation, stipitate glandular and gland-dotted between veins, base attenuate, margin coarsely serrate, apex acute. Synflorescence terminal, corymbose, capitula pedunculate; peduncles 4-7 mm, pubescent; involucre narrowly campanulate, 4-5 mm in diam.; phyllaries 2- or 3-seriate, with scattered short simple eglandular hairs at base, glabrous apically, margin ciliate, apex long attenuate; receptacle conical, epaleate. Florets 35-40; corollas bright lilac-blue, ca. 4.5 mm; corolla lobes long papillose on inner surface, usually glabrous outside or with few simple eglandular hairs; anther appendages longer than wide, apex acute; style base not swollen, glabrous, bright lilac-blue; style branches coarsely papillose. Achenes 2-2.5 mm, 3-5-ribbed, ribs pale, setuliferous or glabrous, body black, with scattered setulae; pappus setae 3.5-4.5 mm, coarsely barbellate, off-white. Fl. and fr. often year-round.

Introduced and becoming naturalized in Guangdong and Taiwan [widespread in South America, becoming weedy in many cultivated areas; introduced and becoming naturalized in E Asia and N Australia].