Prostrate to suberect, perennial herb, fibrous rooted, turning pale or whitish in advanced stage, 15-45 (-60) cm long, often branched from the base, nodes usually thickened. Leaves inear-lanceolate, subglabrous, 5-7.5(-10) cm long, 4-10(-1.5) mm broad, entire but usually with undulated margins, acute; sheaths membranous, whitish 6-9(-15) mm long. Spathes 15-20(-25) mm long, subsessile, cordate at base, falcate or cucullate above, folded, glabrous to sparsely hispid, striated with parallel veins, enclosing 3-5 flowers, bracteolate; bracteoles 3-5 mm long, linear, setaceous; pedicels 5-6 mm long. Sepals unequal, oblong; outer 2-3 mm long, 1-1.5 mm broad; inner 2 keeled, 4-5 mm long, 3-3.5 mm broad. Petals blue, turning pale with age, clawed, c. 8 mm long with suborbicular limb. Capsules c. 4 mm long, suborbicular, 3-celled, 2-valved; seeds c. 2 mm long, black spotted with dull yellow.