Persicaria muricata (Meisn.) Nemoto

Herbs annual. Stems ascending, nearly prostrate at base, 80-100 cm tall, branched, angulate, with retrorse prickles 0.5-1 mm along angles; petiole 0.7-2 cm, sparsely retrorsely prickly; leaf blade ovate or oblong-ovate, 2.5-6 × 1.5-3 cm, abaxially sparsely stellate pubescent, shortly pubescent, with retrorse prickles along midvein, adaxially usually glabrous or sparsely pubescent, rarely stellate pubescent, base broadly truncate, orbicular, or subcordate, margin ciliate, apex acuminate or acute; ocrea tubular, 1-2 cm, membranous, glabrous, apex truncate, long ciliate. Inflorescence spicate, several spikes aggregated and panicle-like; peduncles densely pubescent, sparsely glandular hairy; bracts broadly elliptic or ovate, 2.5-3 mm, apex acuminate, margin ciliate, usually each 2-flowered. Pedicels shorter than bracts, ca. 2 mm. Perianth white or pinkish, 5-parted; tepals broadly elliptic, 2-3 mm. Stamens 6-8, in 2 whorls, included. Styles 3, free; stigmas capitate. Achenes included in persistent perianth, brown, shiny, ovoid, trigonous, 2-2.5 mm, smooth. Fl. Jul-Aug, fr. Sep-Oct.

Nepal, Assam, China.

Anhui, Fujian, Guangdong, Guangxi, Guizhou, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Shaanxi, Sichuan, ?Taiwan, ?Xizang, Yunnan, Zhejiang [India, Japan, Korea, Nepal, Russia (Far East), Thailand].

Wet valleys, ditches; sea level to 3300 m.

Persicaria muricata (Meisner) Nemoto; P. nipponensis (Makino) H. Gross ex Nakai; Polygonum hastatosagittatum Makino var. latifolium Makino; P. kirinense S. X. Li & Y. L. Chang; P. nipponense Makino; P. oliganthum Diels; P. strigosum R. Brown var. muricatum (Meisner) Steward; P. thunbergii Siebold & Zuccarini var. spicatum H. Léveillé; P. uniflorum Y. X. Ma & Y. T. Zhao; Tracaulon muricatum (Meisner) Greene; Truellum muricatum (Meisner) Soják; T. nipponense (Makino) Soják.