Herbaceous perennial, green. Stems 40-80 cm, usually unbranched, quadrangular, purplish below, with very short adpressed or spreading eglandular hairs. Leaves ovate to elliptic, 5-7 x 2-3.5 cm, irregularly serrate to subentire, apically long-attenuate acute, broadly cuneate, with very short eglandular hairs, usually with short leaf shoots in axils; petiole on lower leaves up to 1.5 cm. Verticillasters c. 5, distant from each other, 6-20-flowered, all in axils of upper leaves, sessile. Bracts linear, subulate, 6-9 mm with long spreading eglandular hairs. Calyx 12-14 mm, densely covered with short and long eglandular spreading hairs; tube 6-7 mm; teeth erect-spreading, narrow triangular, acuminate subulate, 6-7 mm. Corolla purplish to lilac-pink, 15-20 mm; tube 7-8 mm, slightly curved, broad; upper lip hooded, densely villous, entire; lower lip with the median lobe reflexed, much larger and longer than laterals and with darker markings. Thecae long pilose when young, glabrescent. Mature outlets not seen.