Perennial herb, 0.2-0.8 m tall, erect from decumbent rooting base, with stems single or few, branched above or almost throughout, with branches curved-ascending. Stems terete, eglandular; internodes 20-85 mm, exceeding leaves or shorter than them. Leaves in perfoliate pairs; lamina (20-)25-70(-80) ´ (7)10-35 mm, broadly or narrowly lanceolate to oblong or oblanceolate, paler beneath, not glaucous, plane, chartaceous; apex obtuse to rounded, margin entire, common base somewhat expanded, rounded; venation: 4-5 pairs of main laterals from lower half to third of midrib, branching and uniting near margin, with tertiary reticulation not prominent, rather lax; laminar glands all pale to mostly black, punctiform, dense; intramarginal glands black, dense. Inflorescencec. 20-40-flowered from 2 nodes, corymbiform, with flowering branches from up to 6 nodes below and uppermost pair sometimes overtopping terminal inflorescence, the whole corymbiform to subpyramidal or cylindric; pedicels 2-3 mm; uppermost bract pair and bracteoles linear-lanceolate to linear, deciduous, other bracts foliar, persistent, all entire. Flowers 6-10(-15) mm in diam., substellate with cupuliform base; buds ovoid, obtuse. Sepals 5, 3-7(-10) ´ 1-3 mm, free, unequal, erect in bud and fruit, oblong to oblong-spathulate or linear-oblong, rounded, entire; veins 5(3), branching outward distally; laminar glands ± numerous, pale and rarely black, striiform to punctiform; intramarginal glands irregular, black, rarely absent. Petals 5, bright yellow, not red-tinged in bud, 4-8(-13) ´ 1.5-4(-7) mm, elliptic-oblong, rounded, margin entire or subentire; laminar glands pale (very rarely a few black), shortly striiform to punctiform; marginal glands black, sessile to subsessile. Stamens 30-42, longest (2-)3-4 mm, c. 0.5 ´ petals; anther gland black. Ovary 3-locular, 2.5-3 ´ 1.5-2 mm, ovoid to narrowly pyramidal; styles 3, c. 2 mm, c. 0.65 ´ ovary, free, outcurving; stigmas broadly capitate. Capsule 6-9 ´ 4-5 mm, broadly ovoid to broadly or narrowly ovoid-pyramidal, exceeding sepals; valves with scattered ovoid to ± elongate amber vesicular glands. Seeds orange-brown, c. 1 mm long, cylindric, not carinate or appendiculate; testa finely ribbed-scalariform.