A small tree 2.5–9 m. tall with scandent branches or a liane 6–20 m. long; stems often forming dense tangles; bark on branches dark plum-coloured, longitudinally fissured; spines slender, 0.4–2.6 cm. long, supra-axillary, sometimes one of the pair developed as a side branch. Flowers in short fascicles on very abbreviated shoots, sometimes appearing before the leaves are fully developed; pedicels 1–6(–8 in fruit) mm. long, hairy or glabrous; buds glabrous or sparsely hairy.