Annuals, to 50 cm tall, simple or occasionally branched. Roots filiform or primary root poorly developed. Stems basally woody. Leaves opposite, alternate upward; petiole ca. 6 mm; leaf blade ovate to rhomboid-ovate, base broadly cuneate to subcordate, margin irregularly and coarsely few serrate. Cymes axillary, 1-flowered, rarely 2- or 3-flowered below. Pedicel to 1.5 cm, sparsely glandular hairy. Calyx ca. 3 mm; lobes ovate-lanceolate to narrowly ovate, apex acute. Corolla red, ca. 6.5 mm; lower lip lobes similar to each other; upper lip slightly longer than lower lip, lobes broadly rounded and with overlapping margins. Stamens as long as lower lip; staminode rounded. Ovary ovoid. Style ca. 2.5 mm, slightly shorter than ovary. Fruit unknown. Fl. Apr-May.

* Low elevations. Jiangsu (Nanjing Shi).