紫背白珠 zi bei bai zhu

Shrubs procumbent, 5–10 cm tall. Twigs terete, slender, slightly puberulous, densely brown hirsute. Leaves towards the ends of branches; petiole 1–2 mm, hirsute; leaf blade gray-green adaxially, elliptic, 1.5–3 × 1–2 cm, leathery, abaxially purple hirsute on veins, adaxially glabrous, secondary veins 2–4 pairs, with fine veins raised abaxially, impressed adaxially, base broadly cuneate to rounded, margin denticulate, denticles setose, apex obtuse to acute, mucronulate. Inflorescences terminal or axillary at apices of twigs, racemose, 5–7 cm at fruiting, 1–4-fruited, glabrous; peduncle 3.5–4.5 cm; bracts ovate, 2–3 mm, leathery, glabrous. Flowers unknown. Pedicels 4–9 mm, glabrous; bracteoles 2, median or above, ovate-triangular, ca. 2 mm, margin ciliolate. Calyx glabrous; lobes triangular-ovate, 1.5–2 mm, margin ciliolate. Corolla and stamens unknown. Ovary hispidulous. Calyx at fruiting dark purple, fleshy; capsule globose, 6–7 mm in diam. Fr. Nov–Dec.

Dominant on rocky slopes near mountain summits; 2000–3400 m. SE Xizang (Mêdog).