1. Breynia officinalis Hemsley, J. Linn. Soc., Bot. 26: 427. 1894.
红仔珠 hong zi zhu
Breynia accrescens Hayata; B. formosana (Hayata) Hayata; B. officinalis var. accrescens (Hayata) M. J. Deng & J. C. Wang; B. stipitata Müller Argoviensis var. formosana Hayata.
Erect shrubs 1-3(-5) m tall, glabrous throughout, much branched; branches terete, slender. Stipules ovate-triangular, ca. 1 mm; petiole 2-3 mm; leaf blade elliptic or broadly elliptic, 2-4.5 × 1-3 cm, membranous, distichous, abaxially pruinose-green or glaucous, adaxially green, base acute to obtuse, apex obtuse to rounded; midvein and (3-)5-7 pairs lateral veins flattened adaxially, elevated abaxially. Flowers small, green, solitary or 2 or 3 in axillary fascicle. Male flowers: pedicels slender, 3-6 mm; sepals 6, broadly ovate, ca. 2 mm, subtruncate at apex; stamens 3, connate into capitate column. Female flowers solitary; pedicels 2-4 mm, hardly lengthening in fruit; sepals as in male, but shorter, 1-2 mm, slightly enlarged in fruit; ovary ovoid; stigmas short, ca. 0.25 mm, free, undivided. Fruiting pedicel 3-4 mm; fruits often elevated by stalk of ca. 2 mm above calyx, ovoid, compressed at apex, ca. 5 mm in diam., apex sometimes obscurely beaked, with shallow apical rim, black-purple when fully mature, red and drying shiny brown. Seeds 3-4.5 × 1.8-2.5 × 1.7-2.5 mm, yellow-brown. Fl. year-round, fr. Jan, Oct.
Thickets, scrub; below 500 m. Fujian, Taiwan [Japan].
All parts are used as medicine for asthma, sore throat, and eczema.
Breynia officinalis has been included within the following, much more widespread species, B. vitis-idaea, but it can be distinguished by the differences in leaf shape (rounded, not acute, apex) and the presence of a basal stalk on the fruits.