Description from Flora of China
Rubus sagatus Focke.
Shrubs scandent, 0.5–2 m tall. Branchlets brownish to brownish red, villous, with intermixed stalked purple glands and sparse, basally broadened and flattened prickles. Leaves imparipinnate, often 3-foliolate; petiole 5–8 cm, petiolule of terminal leaflet 2.5–4 cm, lateral leaflets subsessile, petiolule and rachis villous, with glandular hairs, sparsely prickly; stipules linear-lanceolate, 0.9–1.4 cm, villous, with sparse, stalked glands; blade of leaflets ovate to broadly ovate, 4–11 × 2–8 cm, both surfaces sparsely villous, abaxially with few stalked glands along veins, base rounded to subcordate, margin coarsely sharp doubly serrate, apex acuminate. Inflorescences terminal or axillary, subracemes, 8–20(–25) cm; rachis, pedicels, and bracts yellow villous, with intermixed stalked purple glands; bracts lanceolate, 0.8–1.2 cm. Pedicel 6–9 mm. Flowers 6–8 mm in diam. Calyx abaxially with long yellow hairs and stipitate purple glands; sepals usually erect after anthesis, lanceolate or ovate-lanceolate, 6–9 × 2.5–5 mm, apex acuminate. Petals purple, obovate or suborbicular, 5–8 × 5–7 mm, glabrous, base long clawed, margin premorse or dentate. Stamens many, nearly as long as petals; filaments linear. Pistils numerous, slightly shorter than stamens; styles glabrous or pilose at base; apex of ovary pilose when young. Aggregate fruit red, globose, 8–10 mm in diam., glabrous or slightly pilose; pyrenes distinctly rugose. Fl. Apr–Jun, fr. Jul–Aug.
Mountainous regions, valleys, sparse forests, forest margins, thickets. Low to medium elevations. Fujian, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangxi, Zhejiang.