Ruellia strepens L. - Wild Petunia
Family - Acanthaceae
Stems - To 1m tall, erect, simple or branching, herbaceous, somewhat angled, glabrous or with pubescence in vertical rows.
Leaves - Opposite, petiolate, ovate, ovate-lanceolate, to oblong, typically entire or merely crenulate, glabrous to sparsely hairy, to 15cm long, 6cm wide. Petiole typically winged.
Inflorescence - One or two flowers, on peduncle, from leaf axils near middle of stem. Flowers subtended by a pair of foliaceous bracts.
Flowers - Corolla zygomorphic, to +5cm long, +/-4cm broad, 5-lobed, typically blue. Corolla tube with a constricted portion at base. Constriction white, to 2.5cm long, 3mm in diameter. Expanded portion of corolla tube to +1cm long, 1cm in diameter, pubescent. Corolla lobes +/-1.5cm long and broad, glabrous internally, pubescent externally with some glandular pubescence near the base. Stamens 4, didynamous, adnate at the apex of the constricted portion of the corolla tube. Filaments white, 1.3cm long, sparse pubescent at the base, glabrous above. Anthers yellow, 3mm long. Style -4cm long, sparse pubescent below, white. Stigma 2-lobed, curled. Ovary superior, with some glandular pubescence at apex near style, 4mm long, 1.3mm in diameter, conic, 2-locular. Calyx tube to 5mm long, 5-lobed. Lobes linear-lanceolate, 2-3cm long, 3mm broad, with long and short glandular pubescence, entire, erect. Capsules brown, glabrous, to 2cm long, explosively dehiscing.
Flowering - May - October.
Habitat - Waste ground, disturbed sites, moist, open woods, streambanks.
Origin - Native to U.S.
Other info. - Although the
corolla looks regular, it is typically zygomorphic, with one petal being
slightly larger than the other four. The flowers of this species only last
for one day but the plant produces many flowers while in bloom. This species
is common and reminds many people of the non-related "Petunia" of
Photograph taken at the Kansas City Zoo, 5-28-99, and in the Ozark Scenic Riverways, 6-3-03.