Description from Flora of China
Rubus arcuatus Kuntze; R. rosulans Kuntze; R. tonglooensis Kuntze.
Shrubs low, 0.5–1 m tall. Branches grayish brown, brown or blackish brown, villous, purplish red stipitate glandular, with sparse, needle-like prickles. Leaves simple; petiole 2.5–5.5 cm, with dense purplish red stipitate glands, long hairs, and sparse, needle-like prickles; stipules free, 1–1.5 cm, palmatipartite nearly to base; lobes linear to linear-lanceolate, villous, stipitate glandular; blade suborbicular, 6–12 cm in diam., abaxially densely tomentose-villous when young, glabrate in age, sparsely stipitate glandular along veins, adaxially sparsely villous but more densely so along veins, with sparse, stipitate glands along veins, base deeply cordate, margin 3–5-lobed, terminal lobe slightly larger than lateral lobes, margin irregularly coarsely serrate, apex acute, lateral lobes obtuse, rarely acute. Inflorescences terminal, subracemes, 3–4 cm or slightly longer, several to more than 10-flowered, or flowers few in clusters in leaf axils; rachis, pedicels, and abaxial surface of calyx densely villous, stipitate glandular; bracts 1–1.3 cm, palmatiparted; lobes linear, villous, stipitate glandular. Pedicel 5–10 mm. Flowers 1.5–2(–2.5) cm in diam. Calyx tube cupular, ca. 5 mm; sepals narrowly ovate or narrowly ovate-lanceolate, 0.8–1.5 cm × 5–7 mm, apex acuminate, outer sepals leaflike, margin laciniate or pinnately divided into lanceolate lobes, inner sepals entire. Petals pink, suborbicular, 8–11 mm in diam., barely clawed. Stamens many, shorter than petals; filaments broad, flat. Pistils nearly as long as stamens; ovary and style glabrous. Aggregate fruit red, globose, 8–10 mm in diam., enclosed in calyx; pyrenes densely rugulose. Fl. Jun–Jul, fr. Aug–Sep.
Forests, forest margins; 2300--3400 m. S Xizang (Yadong Xian), NW Yunnan [Bhutan, Nepal, Sikkim].