Sesuvium

Linnaeus

Syst. Nat. ed. 10, 2: 1052, 1058, 1371. 1759

Common names: Sea-purslane
Etymology: Latin Sesuvium, apparently the country of the Sesuvii, a Gallic tribe mentioned by Caesar reason for application to this genus unknown
Treatment appears in FNA Volume 4. Treatment on page 80. Mentioned on page 76, 77.
Herbs [shrubs], annual or perennial, succulent, usually papillate. Roots fibrous. Stems prostrate to erect, forming mats; rooting at nodes in some species. Leaves cauline, opposite, those of each pair equal; stipules absent; petiole bases clasping to ± connate, ± widened, margins usually scarious; blade usually flat, linear to spatulate or ovate, tapered, margins entire. Inflorescences axillary, flowers solitary or in cymes, sessile or pedicellate; bracts absent or 2. Flowers: hypanthium obconic; calyx lobes 5, reddish adaxially, usually hooded near tip; petals and petaloid staminodia absent; stamens [1–]5–30, often connate proximally; pistil 2–5-carpellate; ovary half inferior, 2–5-loculed; placentation axile; ovules to 60; styles 2–5, papillate; stigmas 2–5. Fruits capsules, ovoid to obconic, dehiscence circumscissile. Seeds to 60, black to brown, arillate, usually reniform, shiny or dull, smooth or rugose.

Distribution

Tropical, subtropical, and temperate North America, Mexico, West Indies, Central America, South America, Eurasia, Africa, Pacific Islands, Australia.

Discussion

Species ca. 8 (4 in the flora).

Sesuvium crithmoides Welwitsch, a west African perennial with linear leaves and sessile flowers, has been reported from waste places along wharves in Georgia (J. K. Small 1933); it apparently is not naturalized in the flora.

References

None.

Key

1 Stamens 5; styles and locules 2-3; plants annual > 2
1 Stamens 30; styles and locules 5; plants perennial > 3
2 Seeds smooth, 1 mm Sesuvium maritimum
2 Seeds rugose, 1.5 mm Sesuvium trianthemoides
3 Pedicels 1-20 mm; stems rooting at nodes; seeds 1.2-1.5 mm Sesuvium portulacastrum
3 Pedicels absent or to 2 mm; stems not rooting at nodes; seeds 0.8-1 mm Sesuvium verrucosum