Erect herb, 50-75 cm, branched. Stem and branches puberulent. Leaves thick-or thin-membranaceous, oblong-ovate to ovate, 3-9 by 2.5-5 cm, acuminate, base cuneate to rounded, entire; margin elsewhere serrate or double-serrate; glabrescent above, glandular-punctate beneath; petiole 1-3 cm, puberulent. Spicate raceme terminal, solitary, 4-12 cm long; verticillasters 10-∞-flowered, more or evenly apart. Bracts linear-lanceolate, pubescent, caducous. Calyx tubular, 5-6 mm long, in fruit 6-7 mm, sparingly pubescent and glandular-punctate. Corolla lavender, slender, glabrous, 9-10 mm long. Filaments exserted, bearded below the middle. Nutlets ovoid, 0.6-0.7 mm long, obscurely triquetrous, smooth.
Damp ravines, alluvial forest, thickets, also in mossy forest, ascending to c. 2400 m. Fl. Aug.-March.
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