Shrubby or scandent, ± woody plants with terete or angled stems. Stems usually ridged and striate between the ridges. Leaves opposite or whorled, exstipulate. Inflorescences axillary, cymose, usually pedunculate. Pedicels in one or more seires. Calyx persistent, deeply 5-lobed. Corolla tubular or infundibular, slightly zygomorphic; upper lip emarginate, lower 3-lobed. Stamens 4, didynamous, inserted 1-2 mm above base of corolla. Staminode usually short. Ovary bilocular. Fruit a loculicidal, globose capsule, with enlarged placentae bearing numerous hairs among the seeds. Seeds many, small wingless.

A genus of 45 species, nearly all endemic to Mexico or C. America (Guatemala, Honduras, Venezuela, Cuba, Colombia). Represented in Pakistan by 2 cultivated species. 

In the APG III classification (2009) Russelia is included in the expanded family Plantaginaceae.