Description from Flora of China
Brachystemma ovatifolium Mizushima, Acta Phytotax. Geobot. 16: 42. 1955.
Herbs perennial. Stems diffuse, basally purplish, apically yellow-green, 1--2 m, slightly shiny, branched, pubescent with 2 lines of recurved hairs, somewhat densely pubescent above. Proximal and middle leaves usually broadly ovate or elliptic; distal leaves ovate-lanceolate to lanceolate, (2--)3--10 × (1--)1.5--2.5 cm, both surfaces glabrous, margin ciliate, midvein conspicuous, base nearly rounded, apex acute or acuminate. Flowers numerous in dichotomous, nearly subglobose cymes; distal bracts narrow, membranous, others herbaceous, usually shorter than pedicel, densely ciliate, subglabrous on both surfaces. Pedicel 3--5 mm after anthesis, densely pubescent. Sepals yellow-green, oblong to long ovate, 3--4(--6) × 1--1.5 mm, basal margin pubescent, pubescent outside, subglabrous inside, 3-veined, lateral veins conjoined at apex, base nearly rounded, margin dry, membranous, apex obtuse. Petals minute, ca.1 mm, ca. 1/3 as long as sepals, 2-cleft nearly to base; lobes nearly linear, forked, base entire or undulate-crenate. Stamens 10; filaments ca. 2 mm, base broad, ca. 1/2 as long as sepals, glabrous; anthers pale yellow. Ovary globose or compressed globose, 1-loculed, ca. 1 mm, base narrowed, apex umbonate; ovules 3 or 4; styles 2 or 3, longer than ovary, apex curved. Capsule globose, shorter than persistent sepals, ca. 2.5 mm in diam., 4- or 6-valved. Seed 1, reniform-globose, densely papillate, papillate cells much branched, rotate. Fl. Jul, fr. Nov.
Forest margins, river banks; 2600--2800 m. Xizang [Nepal].