Annuals 30-100 cm tall. Roots yellow-brown, fibrous. Stems erect, 2-5 mm in diam., subquadrangular, narrowly winged on angles, branched. Leaves sessile or subsessile, lanceolate, narrowly elliptic, or elliptic, 1.6-7.5 × 0.4-2.3 cm, both ends attenuate, veins 1-3. Inflorescences panicles of cymes, spreading branched, many flowered. Flowers 4merous. Pedicel erect, 0.5-2 cm. Calyx tube 1-2 mm; lobes free, foliose, linear-lanceolate, 0.8-1.7 cm, apex acuminate, veins 3 and prominent. Corolla pale yellow-green, with purple veins, 1.5-1.8 cm in diam., tube 1-2 mm; lobes linear-lanceolate, 6-8 mm, apex obtuse and apiculate. Nectaries 1 per corolla lobe, pocket-shaped, with an orbicular scale, and many papillose, short fimbriae at apex of pocket. Filaments 4.5-6 mm; anthers yellow, ellipsoid, ca. 2 mm. Style short, distinct; stigma lobes capitate. Capsules ovoid, 6-8 mm. Seeds dark brown, ellipsoid, ca. 0.6 mm; seed coat spongy. Fl. and fr. Sep-Dec.
Open slopes, cultivated ground, beside streams, hillsides, scrub, scattered forests; at elevations from 400-3,000 metres.
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