Small shrubs, up to 60 cm or slightly taller; stems branched at base, branches erect, slender, usually purplish red, with hairs in 2 opposite bands, internode 3-4 cm or longer. Leaves opposite; petiole 1-2 mm or longer; blade thinly papery, lanceolate or ovate-lanceolate, sometimes ovate, 1-5 × 0.6-2 cm, glabrous or scabrid at margins adaxially, subglabrous abaxially, reticulately veined, base very pointed, apex acute or acuminate; lateral veins 4-6 pairs, arched, prominent abaxially; stipules broad at base, long cuspidate upward, 2.5-4 mm, sparsely hairy near base or subglabrous outside. Flowers congested at tips of branches, sessile or conspicuously petiolate for lateral flowers, dimorphic, heterostylous; long-styled flowers with bracteoles membranous, opposite, connate at base, 2.5 mm or slightly shorter, glabrous, abruptly subulate-acuminate. Calyx turning black when dry; tube 2-2.2 mm, glabrous; lobes 5, lanceolate-subulate, ca. 2 mm, stiff, glabrous, usually not ciliate, acuminate or acute. Corolla tube slightly curved, ca. 1 cm, dilated upward, pubescent outside, sparsely pubescent on throat; lobes 5, ovate, ca. 3.5 × 2.5 mm, obtuse and apiculate. Stamens 5, inserted in throat of corolla tube; filaments ca. 2.8 mm; anthers ca. 3 mm, slightly exserted. Style glabrous, 10-11 mm; stigmas 5-lobed, lobes ca. 1 mm; short-styled flowers: style ca. 5 mm, stigmas 3-5-lobed, lobes linear, 2.5-5 mm. Capsule narrowly ellipsoidal, persistent calyx lobes ca. 9 mm, 5-ridged, pale brown, glabrous, 5-valved when mature, with 5 utricle-like pyrenes; seeds linear, embedded in reticulate aril; aril free from testa.
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