Perennial herb 0.3–0.6 m tall, erect to ascending, sometimes rooting, with stems few, unbranched below inflorescence. Stems narrowly 2-lined, eglandular, not glaucous; internodes 25–45 mm, shorter to longer than leaves. Leaves sessile or to 1 mm petiolate, amplexicaul or not, spreading; lamina 20–50(–60) × 5–16 mm, triangular-lanceolate to narrowly oblong or upper triangular-ovate, paler beneath, chartaceous; apex subacute to rounded, margin plane to reflexed, entire or upper leaves sometimes with black-glandular auricles and/or sessile glands or glandular cilia or denticles toward base, base cordate to cuneate; venation: 3–4 pairs of main laterals from lower half of midrib, branched, with lax tertiary reticulation; laminar glands pale, usually sparse or absent; intramarginal glands black, spaced, irregular. Inflorescence 5–c. 35-flowered from 1–3 nodes, rather lax, without or rarely with one flowering branch below, the whole corymbiform or subcorymbiform (round-topped); pedicels 2–3.5 mm or median to 7 mm; bracts and bracteoles lanceolate to linear, black-glandular-ciliate to -denticulate, lower ones with black-glandular-ciliate auricles. Flowers 20–25 mm in diam., stellate; buds broadly ellipsoid, rounded. Sepals 5, equal, very shortly united, 5–6 × 1–1.5 mm, linear-lanceolate, acute, glandular-ciliate; veins 1–3, unbranched, becoming prominent in fruit; laminar glands black, shortly striiform to mostly punctiform; marginal glands black, on cilia. Petals 5, bright? yellow, sometimes tinged red dorsally, 13–15 × 4.5–5 mm, oblong-oblanceolate, rounded to eroded-denticulate; laminar glands black, punctiform, scattered but mostly distal; marginal glands black, dense, distal, sessile or on cilia. Stamens c. 65–80, longest 9–11 mm, c. 0.7 × petals. Ovary 3–4 × 1.5–2 mm, ellipsoid to ovoid; styles 6–8 mm, c. 2 × ovary. Capsule 7-8 × 3.5–4 mm, narrowly ovoid; valves with globose amber vesicles, larger at margins. Seeds not seen.