Endostemon

Perennial herbs or soft shrublets. Leaves subentire or toothed. Inflorescences terminal on main or lateral branches; flowers in 2-6(-12)-flowered verticils; bracts persistent, small or large. Calyx 5-toothed, bilabiate, accrescent; tube campanulate to tubular, gibbous, usually conspicuously ribbed; upper tooth the largest, ovate, erect, conspicuously veined, margin slightly decurrent; 4 lower teeth horizontal, lanceolate-deltoid to subulate or lateral teeth occasionally oblong. Corolla subequally 4-lobed; tube cylindrical, slightly wider at throat; lobes flat or nearly so with uppermost and lowest lobe sometimes longer than 2 lateral lobes. Stamens 4, included, arising above middle of corolla tube; filaments very short, hairy or 0; anthers 1-thecous, reniform. Style included, simple or obscurely bifid. Nutlets suborbicular or oblong, sometimes mucilaginous on wetting. x = 6 (1 report, polyploidy).