Key for Ruellia L.

1Flowers sessile or short-pedunculate in axils of upper leaves
1'Flowers pedunculate, terminally and/or in axils, on conspicuously long peduncles
2Leaves sessile to subsessile, blade linear to narrowly lanceolate, to 1.2 cm wide; corolla 45- 50 mm long
2'Leaves petiolate, blades elliptic to oblong to narrowly obovate, ovate, ovate-elliptic to ovate-oblong to deltoid, 1.2-4.5 cm wide; corollas 18-30 mm long
3Corollas blue or blue-violet, pale purple to violate
3'Corollas brick-red, pale yellow, sulphur-yellow or white with copper-red apex
4Corolla pale yellow, sulphur-yellow or white with a copper-red apex, 25-32(-38) mm long; distal foliose bracts inconspicuous, 10-20 x 1-2 mm; calyx lobes subulate, 5-6 mm long, puberulous, minutely and densely gland-dotted
4'Corolla brick red, 34-50 mm long; distal foliose bracts conspicuous, bicolored, 22-40 x 8-18 mm; calyx lobes narrowly triangular, 3 mm long, glabrous, distinctly gland-dotted
5Much branched, prostrate to procumbent herb; corolla pale purple to violet, 25-30 mm long, tube infundibuliform, 7 mm long, basal portion cylindric, 5 mm long, shorter in length than infundibular upper portion, apically 15 mm wide
5'Erect herb; corolla blue or blue-violet, 18-25 mm long, tube infundibuliform, 14-18 mm long, basal part cylindric, 3-4 mm long, similar in length to infundibular upper part, apically 3.5-4 mm wide