Description from Flora of China
Herbs erect or prostrate, sometimes stoloniferous, hairy or glabrous. Stems 15-40 cm or more tall, pilose or subglabrous when old, young parts densely white villous. Petiole 2-5 cm or more, narrowly winged, sometimes purplish, pilose; leaf blade oblanceolate, ovate-lanceolate to elliptic-ovate, 4-10(-15) × 1.8-4.5(-6.5) cm, villous to strigose, base cuneate-decurrent, margin undulate to irregularly undulate-crenate, ciliate, apex obtuse to acute. Verticillasters 6-12-flowered, in axils of apical and mid stem leaves, apically forming spikes; apical floral leaves bractlike, ovate-lanceolate, slightly longer than verticillasters. Pedicel very short or obsolete. Calyx funnelform, 5-6 mm, veins strigose; teeth ovate, to 1/3 as long as calyx, apically rounded, strigose, gray villous-ciliate at margin. Corolla blue to purple, tubular, 7-9 mm, obliquely spreading, slightly curved near middle, glabrous or pilose, villous annulate inside; upper lip oblong, straight, lobes subovate; middle lobe of lower lip narrowly cordate, emarginate at apex; lateral lobes oblong, as long as or slightly longer than upper lip. Nutlets areole 2/3-3/4 as long as adaxial side of nutlet. Fl. Jan-Mar, fr. Mar-May (or later).
Shady areas in forests, limestone forests, ravines, grassy roadsides; 400-2600 m. Guangdong, Guangxi, Guizhou, Taiwan, Yunnan [Bhutan, India, Laos, Myanmar, Nepal, Thailand, Vietnam]