Annual, diffused herb; branches creeping and rooting from the lower nodes; stem glabrous or pubescent; leaves sessile or petiolate, ovate or elliptic, obtuse or with rounded tip, base auricled on one side, sheath narrowed, bearded at the mouth; spathes 1-3 in the axils, pubescent or hirsute, obconic, funnel shaped or hooded; flowers of upper branch of cyme small, deciduous, lower fertile, upper branch of cyme 2-3 flowered, lower 1-2 flowered or suppressed, sky blue to bluish-violet; sepals 3, membranous, outer one cucullate, inner two often connate at base; petal 3, ovate, unequal, clawed, 2 larger, third one smaller, blue to violet; stamens 3-fertile, filaments glabrous, anthers oblong, one usually larger; staminodes 2, 3, 6-lobed, yellow; ovary trilocular, glabrous, ovules 1 or 2 in anterior locule, solitary or absent in posterior locule; capsules 5-seeded, oblong, trigonous, membranous; seeds closely pitted, oblong, rugose.