Description from Flora of China
Orthodon pauciflorus C. Y. Wu, Acta Phytotax. Sin. 10: 231. 1965.
Herbs erect. Stems (15-)20-70 cm, much branched; branches slender, elongated, retrorse white pubescent, nodes purplish. Petiole 0.5-1.5 cm; leaf blade lanceolate to narrowly lanceolate, 1.5-4 cm × 6-12 mm, papery, adaxially sparsely pubescent, ± conspicuously impressed brown glandular with age, abaxially sparsely impressed brown glandular, sparsely pubescent on veins, base attenuate, margin sparingly serrate, apex acute. Racemes 1.2-10 cm, subcapitate on branches; bracts ovate-lanceolate, 5-6(-10) × 2-4.5 mm, apex acuminate, much longer than pedicels. Pedicel ca. 1 mm, to 2 mm in fruit, pilose. Calyx ca. 3 × 2 mm, to 7 × 4 mm in fruit, white pilose, limb nearly 2-lipped, posterior teeth shorter, narrowly lanceolate, base saccate. Corolla purple, ca. 4 mm, puberulent, bearded just below middle lobe of lower lip inside; tube ca. 3 mm, gradually dilated at apex; upper lip erect, flat; middle lobe of lower lip crenate. Nutlets dark brown, globose, ca. 1.5 mm in diam., pitted with small depressions. Fl. Sep-Oct, fr. Oct.
* Forest margins, streamsides; 1000-1300 m. Guizhou, Hubei, Sichuan.