Herbs perennial. Stems erect, not branched, 30-50 cm tall, longitudinally ribbed, sparsely short strigose. Lower stem leaves mostly withered at anthesis, small; middle and upper stem leaves ± sessile, lanceolate, 2.5-6 cm × 5-12 mm, abaxially finely short strigose, base narrowly cuneate, decurrent, apex acuminate; midvein prominent. Inflorescences dichotomously branched, 4-5 cm, to 6-7 cm in fruit, densely strigose, ebracteate. Pedicel 5-6 mm in fruit. Calyx 5-lobed; lobes oblong-obovate, ca. 2 mm, 1 frequently black orbicular spotted, short strigose, apex rounded. Corolla blue-purple; tube ca. 1.5 mm; throat appendages lunate, pubescent, ca. 0.6 mm, apex emarginate; limb ca. 5 mm wide; lobes divaricate, oblong, ca. 2.8 × 2 mm. Anthers elliptic, ca. 0.7 mm, exserted to throat. Nutlets dark brown, inverted subulate, trigonous-tetrahedral, ca. 1 mm, glabrous, adaxial 3 surfaces subequal in size; abaxial surfaces convex, triangular, acutely 3-ribbed, sessile. Fl. and fr. May-Jul.
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