Limosella

Herbs, annual [perennial], aquatic or paludal; stolons present. Stems stoloniferous, prostrate or ascending, glabrous. Leaves basal, opposite, sometimes rosulate; stipules absent; petiole present or absent; blade fleshy or not, leathery or not, margins entire. Inflorescences axillary, flowers solitary; bracts absent. Pedicels present; bracteoles present or absent. Flowers bisexual; chasmogamous flowers emergent; sepals [4]5, calyx radially or slightly bilaterally symmetric, campanulate, lobes lanceolate to triangular; petals [4]5, corolla white, pink, pale purple, or lavender, slightly bilaterally symmetric, campanulate, not saccate, abaxial lobes 3, adaxial 2; stamens 4, adnate near mouth of corolla, didynamous or equal, filaments glabrous, staminode 0; ovary 2-locular proximally, 1-locular distally, placentation free-central; stigma capitate or slightly 2-lobed. Fruits capsules, ellipsoid to globular, dehiscence septicidal. Seeds 3–200, yellow to dark brown, fusiform or cylindric, wings absent.

Distribution

nearly worldwide.

Discussion

Species 15 (2 in the flora).

Interpretations of morphological and molecular data place Limosella in Scrophulariaceae near the African genera formerly classified as Manuleae Bentham & Hooker f. (P. Kornhall and B. Bremer 2004). Limosella is in need of revision; the characters often used for identification are variable or difficult to observe.

Selected References

Lourteig, A. 1964. Étude sur Limosella L. Publ. Comité Natl. Franç. Rech. Antarct. Biol. 1: 165–173.

Lower Taxa

Limosella aquatica, Limosella australis

Key

1	Corolla lobes acute; stamens attached at different levels; styles 0.2–0.4 mm; leaf blades spatulate to linear; young leaves with auriculate sheaths at bases.	Limosella aquatica
1	Corolla lobes rounded; stamens attached at same level; styles 1 mm; leaf blades linear to filiform; young leaves with tapering sheaths at bases.	Limosella australis