Arenaria serpyllifolia L.

Thymeleaf Sandwort

Arenaria serpyllifolia plant

Family - Caryophyllaceae

Stems - Multiple from base, from taproot, ascending to erect, branching, herbaceous, densely retrorse strigillose, to +/-15cm tall.

Arenaria serpyllifolia stemStem.

Leaves - Opposite, sessile, ovate, acute, entire, glabrous, with antrorse strigillose margins, 3-4mm broad, 6-7mm long.

Arenaria serpyllifolia leaves

Inflorescence - Axillary single flowers or terminal loose cymes. Pedicels elongating in fruit to 1cm, retrorse strigose.

Flowers - Petals 5, white, entire, glabrous, to 3mm long, distinct. Stamens 10, erect. Filaments white, glabrous, 1mm long. Anthers whitish to pale yellow. Styles 3, white, glabrous, -1mm long. Ovary superior, green, glabrous, 1.5mm long, 1mm in diameter, unilocular. Placentation free-central. Ovules many. Sepals 5, glandular pubescent, lanceolate, 1.2mm broad, 4mm long, acute.

Arenaria serpyllifolia flower

Arenaria serpyllifolia calyxCalyx.

Arernaria serpyllifolia fruitFruit.

Flowering - April - August.

Habitat - Glades, fields, bluffs, roadsides, railroads.

Origin - Native to Europe.

Other info. - This tiny plant is common in Missouri but mostly south of the Missouri River. This species can be identified in the field by its small ovate leaves and its small white petals, which are smaller than the sepals.

Photographs taken in Gainesville, FL., 2-11-03, and at Providence Prairie, Lawrence County, MO., 6-18-05.