Samolus parviflorus Raf. - Water Pimpernel

Samolus parviflorus plant

Family - Primulaceae

Stems - Multiple from base, erect, branching, glabrous, terete, from fibrous roots, light green, herbaceous, to 30cm tall.

Leaves - Alternate. Lowest leaves tapered at base to a petiole. Petioles to 1.5cm long. Blades spatulate, entire, light green, subacute at apex, glabrous. Entire leaf to +/-7cm long, -4cm broad. Upper cauline leaves slightly more narrow and nearly sessile.

Samolus parviflorus leaves

Inflorescence - Axillary racemes to +/-7cm long. Pedicels typically jointed, with a small subulate bract at joint, to +1.2cm long in fruit, shorter in flower, spreading. Axis and pedicels glabrous.

Flowers - Corolla white, 5-lobed, +/-3mm broad, glabrous. Corolla tube .5mm long. Lobes truncate to emarginate at apex. Staminodia alternating with corolla lobes, white, .4mm long, 1-5 in number. Stamens 5, opposite corolla lobes, adnate near base of corolla tube. Filaments white, .2-.3mm long, glabrous. Anthers yellow, .2mm broad. Style short, .1mm long, glabrous. Ovary partially inferior, unilocular. Placentation free-central. Ovules many. Calyx tube green, glabrous, .7mm long, 5-lobed. Lobes triangular, glabrous, 1mm long. Calyx accrescent, forming a toothed capsule to 3mm in diameter in fruit.

Samolus parviflorus flower

Samolus parviflorus calyxCalyx.

Flowering - April - June.

Habitat - Streambanks, seeps, low wet woods, lake and pond margins.

Origin - Native to U.S.

Other info. - This little species can be found mostly in the lower 1/2 of Missouri. The flowers are minute, (parviflorus), and the plant is fairly indistinct. The plants habitat and its large, open racemes are good characteristics to use for identification. Grazing wildlife sometimes feed on the plant.

Photographs taken on the banks of the Current River in Van Buren, MO., 6-16-01, and at the Mud Crek Conservation Area, Butler County, MO., 6-11-04.


Back