- Scientific Name: Persicaria capitata (Buch.-Ham. ex D.Don) H.Gross
- Ref: Bot. Jahrb. Syst. 49:277. 1913
- Synonyms: Cephalophilon capitatum (Buch.-Ham. ex D.Don) Tzvelev; Polygonum capitatum Buch.-Ham. ex D.Don; P. repens Meisn.; P. robynsii De Wild.
- English Common Name: pink-headed persicaria, pinkhead smartweed, pink knotweed, Japanese knotweed, pink bubble persicaria
- Chinese Common Name: 头花蓼 tóuhuā∙liǎo, 粉团蓼 fěntuán∙liǎo, 草石椒 cǎo∙shíjiāo
- Japanese Common Name: ヒメツルソバ [姫蔓蕎麦] himetsurusoba
- Family: Polygonaceae
- Genus: Persicaria
- Distribution: Mountain slopes, shaded places in valleys; 600-3500 m. Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangxi, Sichuan, Taiwan, Xizang, Yunnan [Bhutan, N India, Malaysia, Myanmar, Nepal, Sikkim, Sri Lanka, Thailand, Vietnam].
- Photo: Mt. Cang, Yunnan
Herbs perennial. Stems creeping, tufted, ligneous at base, sparsely glandular hairy or nearly glabrous, much branched, rooting from nodes, internodes shorter than leaf blades; branchlet suberect, angulate, sparsely glandular hairy. Petiole 2-3 mm, sometimes auriculate at base; leaf blade sometimes with a large blackish spot adaxially, ovate or elliptic, 1.5-3 × 1-2.5 cm, both surfaces glandular hairy, base cuneate, margin entire and glandular hairy, apex acute; ocrea tubular, 5-8 mm, membranous, sparsely glandular hairy, apex truncate, ciliate. Inflorescence terminal, capitate, solitary or geminate, 6-10 mm in diam.; peduncle glandular hairy; bracts narrowly ovate, membranous. Pedicel very short. Perianth pinkish, 5-parted; tepals elliptic, 2-3 mm. Stamens 8, included. Styles 3, connate to below middle, equaling perianth; stigmas capitate. Achenes included in persistent perianth, black-brown, slightly shiny, narrowly ovoid, trigonous, 1.5-2 mm, densely punctate. Fl. Jun-Sep, fr. Aug-Oct. (Flora of China)