Annuals 15-25 cm tall. Roots yellow, stout. Stems erect, slender, subquadrangular, branched. Leaves subsessile to short petiolate; leaf blade oblong-lanceolate to lanceolate, 1.5-3 cm × 5-7 mm, base narrowed, apex obtuse, veins pinnate. Inflorescences panicles of cymes, spreading branched, many flowered. Flowers 4merous. Pedicel erect, 1-2 cm, subquadrangular. Calyx tube 1-1.5 mm; lobes slightly recurved, linear to linear-lanceolate, 3-5 mm, apex obtuse to acute, midvein distinct. Corolla white, pale blue, or pale blue-green, tube 1-1.5 mm; lobes oblong, 5-6 mm, apex obtuse to acute. Nectaries 2 per corolla lobe, radially elongated, with a narrow scale, and raised margin with few fimbriae. Filaments 3-4 mm; anthers ovoid, ca. 0.8 mm. Style indistinct; stigma lobes capitate. Capsules ovoid-ellipsoid, 8-11 mm. Seeds brown, subglobose, 0.5-0.7 mm in diam.; seed coat warty. Fl. and fr. Aug-Nov.

* Forests; 2300-3500 m. Taiwan (Jiayi Xian).