Suffrutescent, caespitose perennial with basal sterile rosettes. Flowering stems 15–45 cm long, erect, simple or branched, densely to sparsely retrorsely pilose at base or throughout and sometimes retrorsely pubescent, upper parts with sessile glands. Leaves sparsely adpressed pilose with sessile glands. Basal leaves, 1.3–3 × 0.9–2.3 cm, crenate at margin, cordate at base; petiole 1.2–3.4 cm long. Cauline leaves 1.3–4 × 0.5–1.4 cm, ovate to ovate-lanceolate, crenate-dentate at margin, attenuate at base; petiole to 2 cm long. Floral leaves broadly lanceolate to linear-lanceolate, margin entire, longer than lower verticillasters and gradually shorter than upper verticillasters, obtuse to acute at apex, sessile. Verticillasters usually remote, 2–4-flowered, 0.3–3.5 cm distant. Bracteoles few, linear, 1–2.5 mm long. Pedicels c. 1 mm long. Calyx regular, campanulate, 6–7 mm long, densely pilose with sessile glands, ± gibbous at base in fruit; teeth ± equal, triangular, 1.5–3 mm long, slightly recurved, with aristate tips; aristae c. 1 mm long, glabrous. Corolla white, lips streaked and spotted with pink inside, 8–9 mm long, densely short pilose hairy with sessile glands outside; tube 6–7 mm long, shortly exserted from calyx, exannulate; limb bilabiate, upper lip c. 3 mm long, retuse; the lower lip 3-lobed, middle lobe longer than 2 lateral lobes, 4 mm long, emarginate. Style c. 7 mm long, not exceeding the upper lip, glabrous, apex equally bifid; stigmas subulate. Stamens 4, within corolla tube; anthers dithecous, thecae divaricate; filaments flattened and with short swollen hairs near point of attachment to corolla tube. Nutlets 2.5–3 × 1.7–2 mm, oblong–obovoid to oblong-discoid, faintly trigonous, winged near base, blackish brown.
Phenology. Flowering in May and fruiting in mid–May and June.