Herbs or undershrubs.
Leaves opposite, usually petiolate. Inflorescence in simple spike or panicled,
slender or stout, terete or secund. Bracts small, linear to lanceolate. Calyx
ovoid or campanulate, 5-toothed, teeth unequal and often enlarged in fruits.
Corolla tube shortly exserted, straight or incurved, limb 4 or 5-lobed,
obliquely 2-lipped, upper lip erect and notched, lower lip spreading, 3-lobed.
Stamens 4, divergent or distant, slightly unequal, filaments glabrous, anthers
2-celled, cells divaricate. Disk produced behind ovary, oblique. Styles subequally
2-fid with subulate lobes. Nutlets minute, ovoid, smooth or tuberculate.