Procumbent or prostrate, perennial herbs with mostly medifixed pubesence and opposite, decussate, serrate, coriaceous leaves. Inflorescence of short, ovoid to oblong-cylindrical, congestedly flowered, spicate heads. Flowers very small, sessile, zygomorphic, hermaphrodite; bracts short, obovate. Calyx-tube 2-4-dentate, ovoid-campanulate, membranous, persistent. Corolla-tube straight to curved, slightly exceeding the calyx; limb obliquely sub-bilabiate, 4-fid, upper lip entire to 2-lobed, lower lip 3-fid. Stamens 4, didynamous, included or slightly exserted. Ovary 2-locular, with 1 ovule in each locule; style short with oblique stigma. Fruit a small, dry schizocarp, enclosed by or sometimes adnate to calyx, separating into two, 1-seeded pyrenes at maturity.
A small genus of c. 10 species, mainly distributed in North and Central America, with 1-2 species in warmer parts of Asia and Africa; only 1 species found here.
Differs from Lippia Linn., which comprises of erect bushes, subshrubs, shrubs and trees with simple trichomes (not medifined) and ovate or lanceolate, mostly 4-ranked bractlets and spikes not elongating in fruit.
