Ruellia humilis Nutt. - Wild Petunia
Family - Acanthaceae
Stems - Erect, herbaceous, often purplish in strong sun, single or multiple from the base, 4-angled, hirsute to hispid, from short rhizomes, to +/-40cm tall, branching.
Leaves - Opposite, sessile, ovate to ovate-lanceolate, densely long pubescent above and below, entire, subacute at apex, decussate, to +/-4cm long, +/-2.2cm broad. Margins often slightly wavy.
Inflorescence - Flowers sessile in upper leaf axils, subtended by 2 opposite foliaceous bracts. Bracts pubescent as the leaves.
Flowers - Corolla tube to +5cm long. Contracted portion of tube -4cm long, tan, pubescent. Expanded portion of corolla typically lilac, -2cm long, 5-lobed. Lobes rounded, +1cm long, mostly glabrous. Central lower lobe with purple veins. Stamens 4, didynamous, adnate at apex of contracted portion of corolla tube. Filaments white, +/-1cm long, glabrous. Anthers lilac to tan, +3mm long. Style +/-5.5cm long, white to lilac, sparse pubescent (mostly at base). Stigma purple, flattened, 2-3mm long. Ovary green, glabrous, superior, cylindric, 2-locular. Placentation axile. Fruit glabrous. Calyx tube to 2mm long, 5-lobed, green, glabrous. Lobes to 2cm long, 1mm broad at base, linear-attenuate, ciliate-margined. The cilia to 2-3mm long, multicellular. Calyx accrescent.
Flowering - May - October.
Habitat - Dry prairies, glades, open rocky woods, bluffs.
Origin - Native to U.S.
Other info. - This species can be found throughout Missouri.
Photographs taken near Springfield, MO., 7-4-03.