Mimulus alatus Ait. - Monkey Flower
Family - Scrophulariaceae
Stems - To +/-70cm tall, erect, branching above or simple, 4-angled, glabrous, hollow, from thick rhizomes, herbaceous. Angles winged.
Leaves - Opposite, decussate, petiolate. Petiole to 1cm long, with a small wing adaxially. Blade to -10cm long, +3cm broad, lanceolate to lance-ovate, acuminate, shallow serrate to crenate-serrate, glabrous.
Inflorescence - Single flowers from leaf axils. Pedicles 5mm in flower, slightly longer in fruit.
Flowers - Corolla bilabiate, purple. Corolla tube to 1.5cm long, glandular pubescent near apex, glabrous below. Upper lip erect to reflexed, 2-lobed. Lobes glandular pubescent externally. Lower lip 3-lobed. Lobes spreading, glandular pubescent internally and externally., subequal, rounded to obtuse. Central lobe yellow-bearded at base(apex of throat). Stamens 4, didynamous, adnate at base of corolla tube, included. Filaments white glabrous, 6-7mm long. Anthers brownish, 1.3mm broad. Style included, white, glabrous, 7mm long. Stigmas 2, flattened. Ovary 2-locular, light green, glabrous, 6mm long, ovoid-conic. Placentation axile. Calyx tube to 1.7cm long, 5-ribbed, glabrous, 5-lobed. Lobes 2mm long, mucronate. Capsule to +1cm long, many seeded, glabrous.
Flowering - June - September.
Habitat - Stream borders, low wet woods, wet meadows, ditches, springs.
Origin - Native to U.S.
Other info. - Plants of this
genus are easy to ID in the field because of their large, showy, irregular
flowers. The yellow beard on the corolla serves as a guide to bring insects
to the flower and the lobes of the flower serve as landing platforms.
Photographs taken off 53rd Terrace, Platte County, MO., 8-17-00, and in the Ozark Scenic Riverways, Shannon County, MO., 8-12-03.