Plants perennial herbs or shrubs. Leaves simple, margins from entire to dentate or spiny; cystoliths present in random pairs. Calyces 4-lobed, the 2 outer lobes wide than the inner, narrow lobes, of the outer lobes, the upper is often somewhat longer and and the lower one bifid or more obtuse, often with 2 equally strong veins running in parallel from the base; corollas slightly to strongly bilaterally symmetric, funnel-shaped or with a cylindrical tube; stamens 2 or 4, often 2 wtih exserted and 2 included. Capsules 2- or 4-seeded.
Barleria is a pantropical genus with about 300 species, all but one of which are native to the Old World.