Erect shrub up to 2.5 m tall; primocanes erect, dark purple, with rounded angles and deeply furrowed between, with numerous subsessile glands, otherwise almost glabrous to moderately clothed in simple hairs; armature of few, stout, ± erect prickles on angles. Young stems moderately hairy and glandular. Leaflets 5, sparsely pilose on upper surface, pilose on veins but not tomentose on lower surface, serrate or coarsely serrate; terminal leaflet lamina elliptic to elliptic-ovate, acuminate, up to 110 × 75 mm, with petiolule 1/4-⅖ length of lamina. Stipules linear-lanceolate. Infl. densely hairy, with subsessile and some short-stalked glands. Sepals long-acuminate, moderately pilose, but tomentose only on margins and within, without pricklets. Petals rounded, ± crinkled, white. Anthers glabrous.