202. Rubus arcticus Linnaeus, Sp. Pl. 1: 494. 1753.
北悬钩子 bei xuan gou zi
Herbs dwarf, 10–30 cm tall. Roots creeping, nearly woody. Stems greenish or greenish brown, slender, pilose, unbranched or branched. Leaves compound, 3-foliolate; petiole longer, pilose, petiolule of terminal leaflet to 0.5 cm; lateral leaflets subsessile; stipules free, ovate or oblong, 5–7 × 3–5 mm, herbaceous, pubescent, margin entire, apex acute or obtuse; blade of leaflets rhombic to obovate-rhombic, terminal leaflet 3–5 cm, slightly longer than lateral leaflets, abaxially pilose, adaxially subglabrous, base narrowly cuneate, margin irregularly sharply serrulate or doubly serrate, sometimes shallowly incised, apex acute or obtuse. Inflorescences usually terminal, 1–2 cm in diam., usually 1-flowered, sometimes flowers 1 or 2 in leaf axils, bisexual or incompletely unisexual. Pedicel 2–4 cm, pubescent. Calyx turbinate, abaxially pubescent; tube cupular; sepals 5–10, ovate-lanceolate to narrowly lanceolate, 5–8 × 2–3 mm, apex acuminate. Petals purplish red, broadly obovate, rarely oblong or spatulate, 0.8–1.2 cm × 6–8 mm, base clawed, sometimes apically emarginate. Stamens erect, shorter than petals; filaments linear, inflated basally. Pistils 20, glabrous or pilose abaxially, shorter than stamens. Aggregate fruit dark red, semiglobose, not more than 1 cm in diam., with few drupelets, persistent sepals reflexed; pyrenes nearly smooth or slightly rugulose. Fl. Jun–Jul, fr. Jul–Aug. 2n = 14.
Slopes, forests, ravines; ca. 1200 m. Heilongjiang, Jilin, Liaoning, Nei Mongol [Korea, Mongolia, Russia; N Europe].