4. Ruellia tuberosa L., Sp. Pl. 635. 1753. Maheshw., Fl. Delhi 272. 1963; Stewart in Nasir & Ali, l.c. 678; Rani & Mathew in Mathew, Fl. Tamal. Carn. 3(1): 1197. 1982.
KAMAL AKHTAR MALIK & ABDUL GHAFOOR
An erect, up to 60 (-70) cm tall herb with stout, 4-angled stems, swollen and purplish at the nodes, tender parts sparsely hairy. Roots slender, elongated, tuberous. Leaves with up to 2 cm long petiole; lamina oblong-obovate to oblanceolate, 5-9 (-10) x 2-4 cm, shining, basally cuneate to attenuate, entire to ± undulate, obtuse to somewhat acute, often mucronulate. Flowers shortly pedicellate, blue-violet, showy, 5-5.5 cm long, c. 3.5 cm across, solitary or in 1-3-flowered, terminal or axillary cymes; bracts and bracteoles linear-lanceolate, c. 5 mm long. Calyx lobes ± equal, linear, 1.3-2 cm long, ciliate, acute. Corolla pubescent outside, tube c. 3.5 cm long, abruptly narrowed at base, limb 5-lobed, lobes ± equal, ovate, c. 1.5 cm long, patent. Stamens with oblong-sagittate, c. 4 mm long, puberulous anthers. Ovary oblong, c. 4 mm long, glabrous; style 2.3-2.5 cm long. Capsule oblong, 2.2-3 cm long, glabrous or scabrescent, 24-28-seeded, minutely beaked at tip. Seeds flattened, orbicular, c. 2 mm across, hairy.
Fl. Per.: Almost throughout the year.
Type: Habitat in Jamaica, Herb. Linn. 804.4 (LINN).
Distribution: A native of Tropical America; introduced and naturalized in Africa, Pakistan, India to S.E. Asia.
Common in waste places near gardens. Leaves frequently vary from ovate-oblong, narrowly oblanceolate-obovate to broadly obovate within the same individual.