Chylocalyx senticosus Meisner, Ann. Mus. Bot. Lugduno-Batavi 2: 65. 1865; Persicaria senticosa (Meisner) H. Gross ex Nakai; Polygonum babingtonii Hance; ?P. senticosum var. formosanum Ohwi; P. typhoniifolium Hance; Truellum japonicum Houttuyn.

Herbs perennial. Stems trailing or ascending, 1-2 cm tall, much branched, angulate, with retrorse prickles along angles; petiole 2-7 cm, retrorsely prickly; leaf blade triangular or narrowly triangular, 4-8 × 2-7 cm, both surfaces pubescent, abaxially with sparse retrorse prickles along veins, base hastate or broadly cordate, margin retrorsely prickly, apex acuminate; ocrea tubular, 5-10 mm, membranous, apex with green herbaceous reniform-orbicular wing, margin ciliate. Inflorescence terminal or axillary, capitate; peduncles branched, shortly glandular hairy; bracts narrowly ovate, ciliate. Pedicels shorter than bracts, 1.5-2.5 mm, glabrous. Perianth pinkish, 5-parted; tepals oblong, 3-4 mm. Stamens 8, in 2 whorls. Styles 3, connate to below middle; stigmas capitate. Achenes black, dull, subglobose, 2.5-3 mm. Fl. Jun-Jul, fr. Jul-Sep.

Mountain slopes, moist valleys, mixed forests; 100-1500 m. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Shandong, Taiwan, Yunnan, Zhejiang [Japan, Korea, Russia (Far East)].