Erect shrub, 0.6 m, branches divaricate-ascending; branchlets 4-lined, flattened when young, soon 2-lined, eventually terete. Leaves sessile, 8-12 by 2-4 mm, lanceolate to narrowly elliptic, apex rounded, base narrowly cuneate-amplexicaul, concolorous, plane, spreading or ascending; c. 5 main lateral veins, mostly from basal loops, ± parallel, branched above on outer side only, without marked reticulate venation; laminar glands pale, linear near the base, sometimes with rows of streaks or dots on either side, becoming punctate towards apex and margin; intramarginal glands pale and black. Inflorescence 1-flowered, without flowering shoots in uppermost axils or rarely with 1, branching profusely farther down; pedicels shorter than uppermost leaves, 4-8 mm in fruit. Flowers 2.2-2.8 cm ø, ± plane; buds narrowly ovoid, subacute. Sepals 5-7 by 1½-2½ mm, free, imbricate, lanceolate, rounded to subacute, entire; laminar glands pale, mostly linear; submarginal glands pale or occasionally black. Petals bright yellow, 10-14 by 5-6½ mm, obovate, entire, persistent; apiculus almost absent; laminar glands pale, linear, sometimes interrupted distally; submarginal glands absent or 1-3, sessile, black, on or near apiculus. Stamens obscurely 3-fascicled, c. 20, longest 8-9 mm, c. ⅔ as long as the petals, persistent; anthers bright yellow, gland black. Ovary 2½-3 mm, ovoid; styles 3, 2½-3 mm, equalling ovary, divergent; stigmas scarcely capitate; placentas 3, parietal. Capsule 7-9 by 4-5 mm, ovoid, longitudinally vittate. Seeds yellow-brown, c. 0.8 mm, cylindric, scarcely carinate, densely linear-foveolate.